Autumn 2020 EN

www.biogas.org
German Biogas Association | ZKZ 50073
Autumn_2020
BI
The trade magazine of the biogas sector
GAS Journal
english issue
Germany: Only few new bio methane
plants in 2019 P. 6
The transformation of automobile
production P. 22
Vietnam: No strategy for
biogas production P. 37
Including country reports from
Vietnam and South Africa
Fachverband Biogas e.V, Angerbrunnenstr. 12, 85356 Freising
ZKZ 50073, PVSt, DPAG, Entgelt bezahlt 93##
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English Issue
Biogas technology, flexible and tailored to fit
Plants – Components – Extensions – Services
Biogas Journal
| Autumn_2020
Case Study
Biomethane plant with CO 2 recovery
THE PROJECT
The operating company SAS Métha Treil was founded in France
by two livestock farms and two vegetable farms. “In the spirit of our
sustainable business model, we have decided to fully exploit our
resources and focus on the injection of biomethane,” explains
Erwann Bocquier of SAS Métha Treil. “We engaged agriKomp for
the realization, which was able to realize all processes of biogas
production, purification and methane treatment.
“A complete solution was very important to us. One of agriKomp’s
strengths, in addition to 20 years of expertise and convincing
components, is the project management”, emphasizes Bocquier.
The agriPure ® type plant, which was in service in December
2019, went into operation at a processing capacity of 250 Nm 3 /h.
The biomethane produced is fed into the grid. At present, this
represents 8 % of the gas consumption of the community.
Manure, catch crop silage and green waste from the community’s
own farms make up almost 95 % of the input. The plant is
charged by a Vielfraß ® solids feeder and a combined premix unit.
The digestate is separated with a Quetschprofi ® and re-applied as
high-quality fertilizer.
UNIQUE PLANT CONFIGURATION
In addition, the operators realized a plant configuration unique in
France through the recovery and utilization of CO 2 . The separated
CO 2 from the biogas upgrading process is liquefied and sold to
vegetable growers to improve plant growth in their greenhouses.
Approximately 1.500 tons are to be produced per year.
ALL FROM A SINGLE SOURCE CREATES SYNERGIES
“It is always interesting to be involved in the entire planning and realization
process, as this enables synergies. With this holistic concept, the operator has
only one contact person who guarantees the technical availability of the plant.
The clever combination of individual processes increases the efficiency of the
overall system.
At the Métha Treil site a sophisticated heating concept ensures savings.
The recuperation of heat from the CO 2
liquefaction and the compressor as
well as the use of raw gas for heating the digesters enables an additional yield
of 1 % biomethane. Considering these and other measures, savings of up to
80.000 Euros per year can be achieved,” says Nicolas Dromer, head of major
projects at agriKomp.
BIOGAS 2 PLANTS. efficient. flexible. sovereign.
Contact us for more information: info@agrikomp.com | www.agrikomp.com

Biogas Journal
| Autumn_2020
Editorial
Biogas at the
Tipping Point
Dear Readers,
When people talk about the tipping point, they usually
mean the tipping point in the earth’s climate system.
The idea of tipping factors was first published in the
IPCC report in 2001. The article pointed out that human
influence may cause extreme intermittent, irreversible
events to occur in connection with global warming.
This means that, for example, the ice in the Artic and
the Antarctic has melted to such an extent that people
will have to do more than just change their habits to enable
it to revert its former state. To stop our climate system
from tipping, global warming will have to be limited
to a maximum of 2 degrees centigrade – even better, 1.5
degrees centigrade. One way of reaching this target is to
foster use of biogas technology.
And it was this very issue of biogas technology that
the President of the Federal Association of Renewable
Energies e.V. Dr. Simone Peter addressed in July when
she also mentioned the tipping point. At the press conference
for the publication of the industry figures, she
warned that the use of biogas in Germany is at a tipping
point. And our President Horst Seide announced that
growth of the technology is starting to decline.
Although just under 100 new plants were built in 2019
as opposed to a mere total of 15 decommissioned
plants, Fachverband Biogas e.V. expects a significant
decline in the number of existing systems and also in
power and heat supply in 2020 for the first time since
the Renewable Energies Act (EEG) came into effect.
In 2020, there is expected to be a net number of over
160 decommissioned plants, while the number of new
plants will stay constant
The pending Renewable Energies Act amendment will
be a crucial factor in deciding whether the tipping point
for the biogas industry will be exceeded. It will be up
to the policymakers to reverse the trend and thus ensure
that the various positive effects of using biogas
are maintained. But the Federal Government has to act
now to tackle the demands of the industry and the federal
states. Without the necessary framework set by the
2021 Renewable Energies Act to give biogas plant operators
the economic opportunity they need, the decline
will become a very real threat! The industry urgently
needs positive signs.
Both the challenges and the opportunities (of the 2021
Renewable Energies Act) will be important issues at this
year’s Biogas Convention (more on that on page 25). A
lot will be new! Because of the corona pandemic, Fachverband
Biogas e.V. will hold its annual convention in
digital form for the first time. Although digital technology
cannot replace personal and physical interaction,
it may have pushed things past the tipping point from
which the biogas industry will benefit in the future.
Because digitalization will open up new opportunities
and new ways of communication, and in that way may
cut unnecessary traveling times. Less traveling also
means reduced costs and better climate protection. That
is just one more contribution to prevent tipping points in
our climate system. I look forward to welcoming as many
biogas enthusiasts as possible to the digital Biogas Convention
to talk about some of the tipping points.
Warm regards,
Dr. Stefan Rauh,
Director Fachverband Biogas e.V.
3

English Issue
Biogas Journal
| Autumn_2020
Optimum agitator technology for every substrate
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www.eisele.de
Publisher:
German Biogas Association
General Manager Dr. Claudius da Costa Gomez
(Person responsible according to German press law)
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Fax: +49 81 61 98 46 70
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Internet: www.biogas.org
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German Biogas Association
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e-mail: martin.bensmann@biogas.org
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Biogas Journal | Autumn_2020 English Issue
Editorial
3 Biogas at the Tipping Point
By Dr. Stefan Rauh,
Director Fachverband Biogas e.V.
4 Imprint
Germany
6 Biomethane
Only few new plants in 2019
By Dipl.-Ing. agr. (FH) Martin Bensmann
10 Development of Gas Injection
By Dipl.-Journ. Wolfgang Rudolph
10
13 Interview
Conventional natural gas: similar amount
of emissions as oil and coal
Interviewer: Dipl.-Ing. · Dipl.-Journ. Martina Bräsel
16 Using biowaste without the risk of impurities
By Dipl.-Journ. Wolfgang Rudolph
22 Green on the production line? The transformation
of automobile production in Germany
By Dipl.-Ing. · Dipl. Journ. Martina Bräsel
25 BIOGAS Convention International 2020 – Goes Virtual!
26 Charging electric vehicles at the adventure farm
By Christian Dany
30 Combined drive: gas and electric power
By Rouven Zietz
33 Using compost eluate to “boost” biogas plants
By Dr. Sandra Off, Dipl.-Ing. Birte Mähl, Dipl.-Ing. Dietmar
Ramhold and Prof. Dr. Paul Scherer
Country reports
37 Vietnam
Lack of overall strategy on the expansion
of biogas production
By Ms. Le Thi Thoa
30 South Africa
A market waiting to be developed
By Sayuri Chetty and Malett Balmer
CoverPhoto: Ho Thi Lan Huong I Photos: Danpower, Carmen Rudolph, Christian Dany
16
26
5

English Issue
Biogas Journal
| Autumn_2020
Biomethane
Only few new plants in 2019
The number of newly constructed plants that feed biomethane into the natural gas grid
remains stagnant in the lower single-digit range. According to research by our jounalists,
at the end of 2019 there were 206 biomethane feed-in plants in operation.
By Dipl.-Ing. agr. (FH) Martin Bensmann
Five new biomethane feed-in plants were connected
to the German natural gas grid last
year (see Figure 1), which is one plant more
than in 2018. At the end of 2019, a total of
206 plants were feeding biomethane into the
German natural gas grid. Last year, raw gas treatment
capacity reached 4,950 standard cubic meters per
hour (Figure 2). Two of the new feed-in plants were built
in Thuringia, two in Saxony-Anhalt and one in Baden-
Württemberg. In addition, in December 2018 another
feed-in plant started operation in Saxony and is now
included in these statistics. Overall, the plants are distributed
across the German federal states as follows:
Lower Saxony: 31
Saxony-Anhalt: 35 (+2)
Bavaria: 18
Brandenburg: 24
Hesse: 14
North Rhine-Westphalia: 14
Mecklenburg-Vorpommern: 18
Saxony: 14
Baden-Württemberg: 14 (+1)
Thuringia: 11 (+2)
Schleswig-Holstein: 4
Rhineland-Palatinate: 6
Berlin, Saarland, Hamburg: 1 each
The feed-in plants have raw gas treatment capacities
between 650 and 1,500 standard cubic meters per
hour. In total, the raw gas treatment capacity for the
previous year was 4,950 standard cubic meters per
hour. This was 1,050 standard cubic metres greater
than in 2018. The total established raw gas treatment
capacity in Germany increased to 216,415 standard
cubic meters per hour by the end of 2019.
One of the new plants built last year is used for the
fermentation of biowaste. The other four use renewable
raw materials. One of the plants uses membrane technology
to clean the raw gas, two use a physical scrubbing
process, and the fourth plant cleans the raw gas
with amine scrubbing. The fifth plant uses pressurised
water scrubbing.
At an average annual run time of about 8,500 hours,
the 206 plants connected to the natural gas grid can
process 1.83 billion cubic meters of raw biogas. If the
Photos: Hitachi Zosen Inova
6

Biogas Journal | Autumn_2020 English Issue
Set up of a treatment plant in a container where the so-called membrane technology is used.
BIOGASANALYSIS
SSM 6000
the classic for the discontinuous
analysis of CH 4
, H 2
S, CO 2
, H 2
and O 2
with and without gas preparation
* proCAL for SSM 6000 fully
automatic calibration
without test gas
for NO x
, CO und O 2
, several points
of measurements
*
average methane content of the raw biogas
is estimated at 55 percent, because most
of the plants ferment renewable raw materials,
theoretically about 1,011 billion
cubic meters of biomethane could be fed
into the German natural gas grid. This is
equivalent to about 17 percent of the natural
gas produced in Germany in 2019.
The natural gas production in Germany
decreased by about 4 percent in 2019 to
59 billion kilowatt hours (kWh). One percent
of the natural gas consumption in
Germany in the past year was generated by
bio methane. Moreover, the current production
volume is sufficient for providing an
entire supply of biomethane for about 2.8
million German households (consumption
of 3,500 kWh of heat per year).
Outlook: The number of newly constructed
biomethane feed-in plants will likely remain
at a low single-digit level in 2020.
At the time of publishing this Journal, only
two plants were known to be connected to
the grid soon.
2019: The natural gas
consumption has increased
According to the Working Group on Energy
Balances (AG Energiebilanzen), “based on
preliminary data, the natural gas consumption
in Germany in 2019 increased by a
good 3 percent to 982 billion kWh. Several
factors are responsible for this increase.
In particular, the increased use of natural
gas to generate electricity and heat in the
power plants and CHPs of electrical power
providers resulted in a significant rise in
consumption. The weather in the first half
of 2019, which was at times considerably
colder than during the same period in the
previous year, caused turnover to increase
above all in private households, but also
in the commercial, trade and service sectors.
Continual new construction of apartments
heated by natural gas intensified
the increase in consumption. On the other
hand, the economic slowdown resulted in
a decrease in industrial demand for natural
gas, which curbed growth in consumption”.
[...]”The percentage of natural gas in the
overall primary energy consumption increased
by 1.3 % over 2018 to 24.9 %
in 2019. [...] 94.0 % of the natural gas
used in Germany was imported. On balance,
in 2019 nearly 53 billion kWh of
natural gas were fed into storage. Near the
end of 2019, natural gas storage tanks in
Germany were 97 % full. This is the first
time that storage tanks have been this full
at the end of a year. According to initial
figures, 9.8 billion kWh were supplied to
the German natural gas grid from biogas
processed to natural gas quality. In 2018,
10.3 billion kWh were supplied. Nearly 8
billion of these kWh were used to generate
electricity; about 0.5 billion kWh were
used for fuel; about 0.5 billion kWh were
part of the turnover in the heating market
(space heating, hot water). Another 1.0
billion kWh were used in material applications,
exported or used in other ways”.
[...]”Germany is to a considerable extent or
entirely a net importer of fossil fuels (hard
coal, mineral oil, natural gas).In 2018, energy
consumption was covered by imports
of 88 % of hard coal, 99 % of petroleum
and 97 % for natural gas. In contrast,
FOS/TAC
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SSM 6000 ECO
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Tel +49 (0)30 455085-0 I info@pronova.de
7

English Issue
Biogas Journal
| Autumn_2020
Figure 1: Development Entwicklung of biomethane der Zahl der feed-in Biomethaneinspeiseanlagen plants in Germany, annual in Deutschland, expansion jährlicher since 2006 Zubau seit 2006
35
35
30
32
29
25
20
19
23
15
17
16
10
5
0
10
7
5 5
3
2 3
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
Source: German Biogas Association, Status as of: 15 th April 2020
Quelle: Fachverband Biogas e.V., Stand: 15. April 2020
Entwicklung
Entwicklung
der
der
Rohgasaufbereitungskapazität
Rohgasaufbereitungskapazität
in
in
Nm
Nm 3 /h 3 /h
in
in
Deutschland,
Deutschland,
jährlicher
jährlicher
Zubau
Zubau
seit
seit
2006
2006
und
und
kumuliert
kumuliert
Figure 2: Development of raw gas treatment capacity in Nm³/h in Germany, annual and cumulative since 2006
250.000
250.000
200.000
200.000
175.165
175.165
190.465
190.465
202.665
202.665
207.565 211.465
207.565 211.465
216.415
216.415
150.000
150.000
125.065
125.065
151.915
151.915
100.000
100.000
89.865
89.865
56.665
56.665
36.835
50.000
36.835
50.000
33.200 35.200
28.250 33.200 35.200
28.250 19.830
26.850 23.250
19.830
26.850 23.250 15.300
3.950 15.300
3.950 8.585
12.200
1.000 8.585
12.200
1.000 2.950 4.635 4.900 3.900 4.950
2.950 4.635 4.900 3.900 4.950
0
0
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
Annual Jährl. Zubau increase d. Rohgasaufbereitungskapazität of raw treatment capacity in Nm³/h
Jährl. Zubau d. Rohgasaufbereitungskapazität in Nm³/h
Quelle: Source: Fachverband German Biogas e.V., Association, Stand: 15. Status April as 2020 of: 15 Cumulative Kumulierter increase Zubau d. of Rohgasaufbereitungskapazität
raw treatment capacity
Quelle: Fachverband Biogas e.V., Stand: 15. April 2020
th April 2020
Kumulierter Zubau d. Rohgasaufbereitungskapazität
100 % of the consumed lignite was provided from native
resources and the nearly all of the energy from
renewable resources came from native production. In
total, Germany relied on imports of 71 % of its energy
supply in 2018.
In general, this situation did not change in 2019. Due
to the complete stoppage of domestic production at
the end of 2018, dependency on imports for hard coal
increased to 100 % in 2019. At the same time, native
production of lignite decreased by 21 % and that
of renewable energies increased by 6 %. For electrical
power, the export surplus of 2019 continued, though
it decreased with respect to the previous year by 58
PJ (or more than 16 billion kWh). Based on the initial
calculations, these changes (with an overall decrease in
primary energy consumption) reflect a slight increase in
the import ratio; dependency on imports will likely still
be nearly 71 % in 2019.
Author
Dipl.-Ing. agr. (FH) Martin Bensmann
Editor, Biogas Journal
German Biogas Association
+49 54 09/90 69 426
martin.bensmann@biogas.org
8

Biogas Journal | Autumn_2020 English Issue
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English Issue
Biogas Journal
| Autumn_2020
Development of Gas Injection
The Flex CHP unit with
an output of 1.1 megawatt
works according
to a schedule based on
demand. The continual
supply of heat during
downtimes is ensured
by a heat accumulator
with a storage capacity
of 100 m³.
Danpower has optimally equipped the biogas plant in Gröbern for the future with
an additional fermentation level, gas treatment and a FlexCHP system.
By Dipl.-Journ. Wolfgang Rudolph
The biogas industry has undergone an intense
period of change over the past two decades.
This fact is particularly illustrated by the
development of the biogas plant in Gröbern
near the city of Meißen (Saxony). Biogas
production was set up there on a landfill site in 2007
by a group of investors based in Lichtenstein. Besides
generating renewable power, the aim was to recover the
heat needed to dry sewage sludge on the site instead of
using oil-fired boilers and to heat the landfill operator
buildings.
The sludge was fermented in two square horizontal digesters
with a volume of 1.250 cubic meters (m³) each
and horizontal agitators. Only maize silage mixed with
recycled matter was used as input. When the drying
process was discontinued in 2010, the biogas plant
became economically less viable and would probably
have been closed down if the Danpower Group had not
acquired it in 2013.
Based in Potsdam, Danpower is wholly owned by Stadtwerke
Hannover AG. The heat supply and contracting
company has various subsidiaries throughout Germany
that operate or supervise both gas processing biogas
plants and combined heat and power plants. The biomethane
financially provided by the natural gas grid
enables climate-friendly power and heat prescribed by
the Renewable Energy Law to be generated for housing,
commerce, and industry in over 80 communities,
mainly in the eastern part of Germany.
High-energy sugar beet pulp at a second
fermentation level
After the takeover, Danpower extensively modernized
the plant for a total of 11.5 million euros over a construction
period of two years, thus getting it into shape
to meet future requirements. That included adding two
more digesters to the plant. Each of the round concrete
containers has a capacity of 5,000 m³. In addition, the
volume of stored gas was increased to 3,600 m³ by
covering the container with double membranes.
“Besides enhancing performance, the fermentation
level integrated in the pulp flow enabled substrates to
be used in the form of sugar beets grown in the region
known as Lommatscher Pflege that is characterized by
its good soil,” says Karsten Krieg, who is the director of
the subsidiary Bioreg GmbH. The farmers are very happy
about this sales potential, as the traditional marketing
lines for sugar beets collapsed after the shutdown
of the sugar plant in Brottewitz.
After stones and soil are removed by vibrating sieves
and brushing rollers, the supplied sugar beets are
stored in a slap silo as whole fruit. Before the sugar
PHotos: Danpower
10

Biogas Journal | Autumn_2020 English Issue
beets go into the Havelberger 100 m³ volume sliding
floor doser, they go through another round of mechanical
cleaning.
Beet pulp combined with maize
The beet pulp is then funneled and transported via a
screw feeder into the front chamber of the “Bio-Mix”
pump made by Wangen, where it is mixed with recycled
material. Then the connected eccentric screw pump
conveys the mashed substrate into the first of the series-connected
round fermenters. Here the beet pulp
meets the maize silage that has not fully fermented
after a period of around 20 days in the rectangular fermenter
and is therefore still biologically highly active.
“That not only generates residual gas potential from the
first fermentation level. So many microbes keep flowing
into the round digester together with the extensively decomposed
maize fibres that the high-energy beets are
almost entirely converted to biogas in a stable fermentation
process without the risk of acidification,” says
the 47-year old Process Engineer.
The sugar beets could also be fermented in one single
container. But when the plant was designed, the company
opted for two digesters that worked redundantly to
ensure operational safety. According to Krieg, the idea
behind this was that an accumulation of sand cannot
be avoided when the beets are put in. If cleaning is
required, this can be done at each of the containers alternately
without interrupting the production of biogas.
Since the facility’s upgrade, around 50,000 tons of
substrate have been used every year, approx. half of
each consists of maize silage and sugar beets. Part of
the fully fermented material is pressed off by a separator
before it is fed into the storage tank. Additional
benefit: It is easier to store the separated solids and in
particular to transport them for use as fertilizer. A total
of 32,000 tons of liquid digestate and 5,000 tons of
solid fraction are produced every year.
Innovative approach to biogas upgrading
Since the plant complex was modernized, 90 percent
of the 11.5 million m³ of the biogas produced each year
has been upgraded to natural gas quality and once it
has been compressed to 50 bar, has been fed into the
natural gas grid of Ontras Gastransport GmbH. Converting
a maximum of 1,200 standard cubic meters (Nm³)
of raw biogas to 600 Nm³ of biomethane is done by
physical scrubbing at a plant run by Schwelm.
It operates on the principle of pressure swing adsorption,
in which the varying solubility of the main components
in biogas, carbon dioxide (CO 2
) and methane
(CH 4
) is applied. This effect is heightened by increased
pressure and by a temperature increase that results
in the columns. The CO 2
dissolves almost completely
in the liquid, while the biomethane with a content of
around 98 percent is discharged over the dome of the
reaction tank, dried and conditioned before being fed
Karsten Krieg, Director of BIOREG
Energy & Recycling GmbH.
into the grid by adding liquid
gas to the biomethane.
As it expands, just like when
a bottle of carbonated drink is
opened, the CO 2
in the flash
column is released from the
liquid. Once the CO 2
is fully
removed, blowing in air makes
the liquid receptive again. The
gas mixture of air and carbon
dioxide (stripgas) still contains
small amounts of methane. The
regenerative thermal oxidizer
(RTO) for post-combustion has
the job of removing this residual
quantity from the exhaust gas.
CO 2
scrubbing with an alcohol solution
One of the special features of the upgrading concept
developed by Schwelm is that instead of water that is
usually used for physical absorption, an alcoholic solution
(solvent) acts as a medium to scrub the CO 2
. “That
prevents biological contaminants that are carried along
from being retained in the containers of the column.
That increases service reliability and saves costs,” says
Krieg when mentioning the advantages.
The operating company generates power and heat
from the remaining raw biogas. The CHP plant has an
electrical power capacity of just under 1.1 megawatts
(MG). As it supplies the power according to an arranged
schedule based on demand, it only runs for 2,000
hours per year. The resulting thermal energy is sufficient
to supply the buildings of the Nero GmbH landfill
operator with heat as stipulated in the contract. An interconnected
heat accumulator with a volume of 100
m³ ensures continual heat supply, despite the flexible
operation and resulting interruptions that occur during
operation of the CHP plant.
According to Danpower, the modernization and expansion
of the plant will ensure the operation of the biogas
plant in Gröbern for a long time. Once the initial
funding period has expired in 2027, there are plans
to participate in calls for tender to pave the way for
subsequent funding until 2037. According to the
Gas upgrading by Schwelm Alagentechnik GmbH
works on the principle of pressure swing adsorption.
An alcohol solution is used instead of water as a
medium to scrub the CO 2
.
11

English Issue
Biogas Journal
| Autumn_2020
director, sales of biomethane are guaranteed, as the
CHP units that use it to generate energy throughout
Germany mostly went into operation between 2012 and
2013 and therefore will be receiving Renewable Energy
Law funding for some time to come.
Problems caused by the elimination of
avoided grid charges
“The anticipated elimination of the share in the socalled
avoided grid charges gave us cause for concern,
as they are an essential part of the profitability of biogas
plants with biomethane upgrading,“ Krieg admits. This
grant is governed by the Gas Network Access Regulation
that prioritizes renewable gases, similarly to electricity,
and obliges the gas grid operators to purchase the gas.
Legislature also assumes the grid operators will save
on operating costs if the gas is fed into the grid and is
used regionally instead of being acquired from Russia
or Norway and transported to the consumer from far
away. The regulation specifies that the cost benefit due
to “avoided grid charges” has to be passed on to the
input sources.
“But this is limited to a period of ten years. As we didn’t
start feeding into the grid in Gröbern until 2014, the
rule for us would expire in 2024,” said the director. Although
possible subsequent funding is currently being
discussed, Danpower is also working on concepts for
better profitability of biogas production, e.g. by direct
sales of biomethane as fuel or as a raw material in the
chemical industry.
He said that there are talks with gas traders, who supply
the chemical companies, and with forwarding agents
and bus companies whose vehicles are in service in residential
areas. Tighter environmental regulations would
be of mutual benefit. Current efforts to apply market
mechanisms to promote sustainability would also lead
to further value-creating opportunities beyond the Renewable
Energy Law funding, namely by selling CO 2
reduction certificates. “Of course, that’s a great challenge.
On the other hand, the different overall conditions
have apparently boosted technology. And that can
really benefit the future of the biogas industry,” says
Karsten Krieg.
Author
Dipl.-Journ. Wolfgang Rudolph
Freelance Journalist
Rudolph Reportagen - Agriculture,
the Environment, Renewable Energies
Kirchweg 10 · 04651 Bad Lausick, Germany
+49 3 43 45/26 90 40
info@rudolph-reportagen.de
www.rudolph-reportagen.de
Biogas Convention
vom 16.–20.11.2020
» energie- und Klimapolitik,
Zukunftsprojekte, Düv, awsv,
tras, rote gebiete, emissionen,
gärprodukte, Praxisberichte
(Vorträge in Deutsch)
Biogas Convention international
vom 08.–12.12.2020
16. – 20. November 2020
18 – 20 November 2020, Hanover, Germany
2020 goes
virtual!
» the future of Biogas, german
Biogas Competence, standards,
Biomethane, Best practice,
international projects, innovations
(presentations in English)
08. – 10. Dezember 2020
www.biogas-convention.com
12

Biogas Journal | Autumn_2020 English Issue
A switch from coal and
crude oil in the electricity,
heating and transport
sectors with fracking
natural gas, as the federal
government is aiming for
with the LNG terminals,
would strengthen the
greenhouse effect when
switching from coal to
natural gas by around
40 percent.
Interview
Conventional natural gas: similar
amount of emissions as oil and coal
In September 2019, shortly before the German federal government passed resolutions
about reaching climate protection goals, the Energy Watch Group (EWG) presented the
newest scientific information regarding the suitability of natural gas for future use. The
study calculated the climate effects of natural gas based on current research about
methane and CO 2
emissions over the entire supply chain. Hans-Josef Fell, co-author of the
study and President of the EWG, is calling for rethinking the current political debate about
the future of the energy sector. We spoke with him about the results of the study and the
political and economic background.
Interviewer: Dipl.-Ing. · Dipl.-Journ. Martina Bräsel
Photo: EyeUbiquitous_FOTOFINDER.COM
Biogas Journal: Mr. Fell, why was the study carried out?
Hans-Josef Fell: The time window for preventing dangerous
climate change will be closing in just a few
years. Climate protection can only succeed if worldwide
emissions contain almost no climate endangering
gases by 2030. Unfortunately, despite international
UN conventions and countless agreements, climate
emissions reached a new high in 2018. In 2019, global
warming already reached 1.1 degrees Celsius. We are
experiencing extreme weather and an accelerated rise
in sea level all over the world.
However, not only global CO 2
emissions, but also rising
methane emissions are causing increasing damage to
the climate. In recent years, climate researchers have
determined a continuous increase in methane concentrations
in the atmosphere. Scientists discovered that
increased consumption of natural gas is the cause. And
the proportion of methane among all greenhouse gases
is already 41 percent.
Biogas Journal: The result of the study is that natural gas
does not contribute to climate protection, but instead,
even accelerates climate change. Why is that?
13

English Issue
Biogas Journal
| Autumn_2020
Fell: Over the last ten years, natural gas consumption
has risen more quickly than that of other fossil energy
sources, resulting in a proportionate increase in global
carbon emissions. With conventional
natural gas, which is still
transported primarily through
pipelines, we see emissions at
a level similar to oil and coal.
But the use of these energy
sources continues to decrease.
Natural gas is now obtained to
a greater extent by fracking. In
this controversial process, rock
is broken open by deep drilling
followed by directing water into
the deposit at high pressure.
In addition to increasing emissions
from natural gas production,
which are the main source
Hans Josef Fell
for the rise in atmospheric methane, there is a second
effect: Methane is 20 to 30 times more dangerous to
the climate than CO 2
when considered over a period of
100 years. But effective climate protection must result
in zero emissions in 10 years, so it only makes sense to
consider a period of 20 years at most with regard to the
climate effects of methane. In this case, however, the
climate intensity of methane is even 80 to 100 times
greater than CO 2
.
So the widespread image of natural gas as a bridging
technology that protects the climate is just not correct:
We have also come to the conclusion that the high
methane emissions related to natural gas far outweigh
any savings of CO 2
. Indeed, converting the coal and oil
used in the electricity, heat and transportation sectors
to natural gas obtained by fracking, as the German federal
government is attempting with the LNG terminals,
would increase the greenhouse gas effect by about 40
percent.
Biogas Journal: The federal government’s climate package
is finalised. A paper outlining the key points addresses
measures for how Germany wants to decrease
its CO 2
emissions incrementally in accordance with the
European climate protection agreement. The target is
to release no further CO 2
into the environment than nature
can reabsorb by 2050. What do you think of the
package?
Fell: The federal government’s climate protection
policies are leading us directly toward a climate catastrophe.
The so-called climate protection package is
nothing but a fraud. Headlines point to sham activities
that, in the end, generate greenhouse gas emissions in
Germany that are much too high. For example, the federal
government wants to prohibit the new construction
of oil heating systems starting in 2025. But the many
exceptions in the rules prevent this from happening. In
its current form, the measure will come to absolutely
nothing and will have no effect on climate protection.
Moreover, the conversion of coal-based electricity and
oil-based heat to natural gas even accelerates climate
change due to the methane emissions in the upstream
supply chain. Greater methane emissions will result
due to additional demand for natural gas. Scrapping
premiums for replacing oil heating systems should only
be available in the case of conversion to climate neutral
heat based on renewable energies.
Annual subsidies in Germany for natural gas totalled
1.4 billion euros in 2017. Germany also supports the
infrastructure for continuing to increase natural gas imports
with LNG. That is counterproductive. Subsidies
support the system and intensify the problem.
Biogas Journal: The expansion of solar, wind and hydropower,
geothermal energy and bioenergy is moving at a
very slow pace in Germany at the moment. What must
be done to build up a future-oriented energy system?
Fell: In total, the use of fossil raw materials is responsible
for at least 60 percent of global greenhouse
emissions. Renewable energies and the related, costeffective,
zero emissions technologies that enable a
comprehensive and quick transition to a climate friendly
energy system represent the alternative to current
fossil energy systems.
We have proven that a complete, global energy supply
is possible by using just renewable sources and that it
is even less expensive. The primary sources will be solar
and wind energy in connection with batteries, electrical
drives and heat pumps. But hydropower, geothermal
energy and bioenergy also play a very important role.
The existing infrastructure can already be used now for
biogas and green gas.
Biomethane is important, but the methane problem
must be completely prevented here as well. I see this
as one of the significant tasks for the biogas industry.
If they are successful, biogas can make a very valuable
contribution. Converting to 100 percent renewable energies
must be implemented by 2030.
Biogas Journal: A variety of methods can be used to produce
hydrogen. Electrical current is used in the electrolysis
of water, but there are also thermal processes
such as the steam reforming of methane or biomethane,
or the pyrolysis of coal or biomass, which are among
the conventional methods. What is green hydrogen and
why is it essential to climate protection and the energy
transition?
Fell: Green hydrogen is climate friendly because it is
produced by green electricity through electrolysis or
obtained by biotechnological processes such as from
algae. It provides significant support for climate protection
and the energy transition. Green hydrogen can be
used in transportation in drives powered by fuel cells,
and it provides an ideal long term storage method to
hold excess solar power generated in the summer for
14

Biogas Journal | Autumn_2020 English Issue
use in the winter and to replace fossil energy sources
in the chemical industry or steel manufacturing. Bridging
technologies with blue hydrogen, which is produced
from fossil raw materials, should not be allowed.
Biogas Journal: What is your evaluation of the federal
government’s hydrogen strategy?
Fell: A strategy with hydrogen produced by natural gas
does not support the climate, but the federal government
strongly promotes it anyway. In addition, hydrogen
is supposed to be imported from Northern Africa.
Although the solar radiation is more intense there, the
high costs associated with building the necessary infrastructure
would be more expensive than hydrogen
produced in Germany with solar power. Importing green
hydrogen from Northern Africa can represent a valuable
contribution, but only as a supplement to domestic
green hydrogen production. But the federal government
does everything it can to prevent the expansion of green
electricity and biogas, and in so doing, it removes the
foundation for domestic green hydrogen. In this way,
the government is increasing German dependency on
imports in the energy sector with all the associated geopolitical
and financial risks.
Biogas Journal: From your perspective, what urgent action
is required?
Fell: We should resurrect the expansion of green electricity.
The past has shown that this works best when we
include citizens in the process. People can participate
though cooperatives or other citizen-based investment
options, which create acceptance for the project in the
area.
But this is only possible with a fixed feed-in tariff, not
with tendering. Switching to a tendering process had
devastating consequences in this regard. That is why
there is hardly any investment anymore in the biogas
sector and far too little investment in the solar sector.
Investment in the area of wind power also fell apart with
the conversion to the tendering process. Tendering only
makes sense for very large projects like offshore wind
parks, for example. In the range up to 40 megawatts
we need citizen engagement with a fixed feed-in tariff.
METHATEC ® DETOX S DIRECT
The next level of desulphurisation
Biogas Journal: Mr. Fell, thank you very much for the
interview!
Interviewer
Dipl.-Ing. · Dipl.-Journ. Martina Bräsel
Freelance Journalist
Hohlgraben 27 · 71701 Schwieberdingen
+49 71 50/9 21 87 72
braesel@mb-saj.de
www.mb-saj.de
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English Issue
Biogas Journal
| Autumn_2020
Using biowaste without
the risk of impurities
Biogas production with the BEKON dry fermentation method is, for the most part, not
sensitive to impurities, which allows the German city of Dessau-Roßlau to use more than
12,000 tonnes of biowaste per year to generate energy since 2019.
By Dipl.-Journ. Wolfgang Rudolph
For the city of Dessau-Roßlau, there are many
good reasons to operate a biowaste digestion
plant. The main reasons mentioned by mayor
Peter Kraus in April 2018 at the groundbreaking
ceremony for the construction of
the plant include the efficient use of natural resources
along with environmental and climate protection. But
the city councils of this community, with 80,000 residents
the third-largest in the state of Saxony-Anhalt,
had other direct economic benefits in mind when they
commissioned a feasibility study back in 2010 for constructing
a biowaste digestion plant, including a postrotting
process.
At that time, household biowaste was transported to
composting facilities in Vockerode and Oranienbaum.
The disposal vehicles drove at least 30,000 kilometres
per year just for those deliveries. In contrast, the site for
biowaste digestion considered in the study was located
within the city on the site of a household waste landfill
that had not been used since 2009.
Connected to the existing heat grid
The site at the “Scherbelberg” landfill, a 47-metre
mound, is now being used as a place to deal with and
collect all kinds of waste. The existing infrastructure
such as secure access roads and scales yielded synergies
for operating a biowaste digestion plant. In addition,
the site’s location in the south-western part of the
city makes it easier to use the biowaste to the fullest
extent possible to produce energy. Indeed, in addition
photos: Carmen Rudolph
16

Biogas Journal
| Autumn_2020
Delivery of collected
biowaste to the
collection hall of the
biowaste digestion
plant in Dessau-
Roßlau.
Sabine Moritz, manager
of municipal operations
for city maintenance:
“Dessau-Roßlau
created a basis for
the sustainable and
environmentally sound
use of the community’s
biowaste by building
the biowaste digestion
plant”.
to the electricity that is generated, the
produced heat can be fed into the district
heating grid. In this regard, it made sense
to continue using the heat transfer station,
which had previously been used to feed the
thermal energy generated while converting
landfill gas to electricity
The best collateral for successful biowaste
digestion, however, is the stable generation
of biowaste – about 12,000 tonnes annually.
In Dessau-Roßlau, this is achieved
through the collection system introduced
at the beginning of the 1990s. “The residents
of Dessau-Roßlau like to use their
biowaste bins,” says Sabine Moritz, who
manages the municipal operations for the
city maintenance. Even in the “garden colonies”,
where biowaste bins are available
seasonally, people diligently and cleanly
separate biowaste from other waste materials
for the most part – as they do elsewhere
all over the city. So, in the spring
of 2018, plans were started to implement
the largest investment ever made by the
municipal company. The project was ambitious,
also due to the time constraints. To
ensure a seamless transition from converting
landfill gas to electricity to producing
energy from biowaste while simultaneously
keeping the advantages of the German Renewable
Energy Act (EEG) rules of 2014,
the biowaste digestion plant had to go into
operation by the end of 2018.
Pre-fabricated construction
components
Indeed, BEKON GmbH was successful in
implementing this project, with an investment
volume of 6.4 million euros, within
the required time frame of eight months.
“The pre-fabricated modules, such as the
rear walls of the fermentation chamber,
which featured fully integrated connections,
really supported our efforts. On the
narrow access roads, though, that made
for a lot of circling around,” remembers
Moritz. BEKON, a plant engineering company,
was awarded the project after a Europe
wide tendering process. The project
also included managing plant operations
for five years. BEKON commissioned
KOMPOTEC GmbH to do that work. Both
companies are part of the Eggersmann
group.
The composting facility for the post-rotting
of the fermentation residue was constructed
on the 8,000 square metre plateau atop
the former landfill. This work was done by
TS Bau GmbH for about two million euros.
Since the end of 2018, the city’s biowaste
has been converted into energy in these two
facilities and then processed into compost.
The city uses special vehicles with rotating
drums to mix the contents of the biowaste
bins, each of which has a capacity of 120
or 240 litres, during the waste col-
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17

English Issue
Biogas Journal
| Autumn_2020
At regular intervals, and particularly before opening the digester
gates, plant manager Ronny Raupach uses a hand-held device to
measure the gas composition in the fermentation chamber.
A view of the control equipment for the containers in the percolate system. At rear is the
additional hygienisation system that can be used so that the excess amounts of waste can be
marketed as organic fertiliser. At centre is the sand trap and the percolate collection tank is
at the front.
The roller door at the
entrance to the collection
hall of the biowaste
digestion plant opens
by sensor control when
a collection vehicle
backs up toward it.
At right are valves for
removing samples of
percolation liquid and
the chemical containers
for the acidic scrubbing
of the exhaust air
purification system.
lection runs. They dump their loads onto a storage area
about 200 square metres in size in the collection hall.
From here, a front loader brings the material, without
any further processing, to one of the five garage-shaped
chambers. The access gates to the fermenter tunnels,
which are 6.5 metres wide, 4.5 metres high and 20 metres
long are located on one side of the closed collection
hall, which is equipped with an exhaust air purification
system.
Fermentation period of 21 days
The fermentation chambers are loosely filled to a height
of up to 2.7 metres based on a schedule according to
the seasons. “In the winter months, when the amount
of biowaste is lower but of higher quality with respect to
energy generation than in the summer because it does
not contain as much green waste, we fill one tunnel per
week and two tunnels every three weeks. From spring
A double membrane container on the roof is used to
collect the biogas produced in the percolate storage
tank and the five fermenters.
through fall, when the vehicles deliver more than 1,000
tonnes per month, we fill two tunnels every 14 days
and between that, one tunnel per week,” explains plant
manager Ronny Raupach. The material to be fermented
remains in the digester for an average of 21 days. After
the tunnel is filled, the gate is locked and it is sealed
with inflatable hose seals to make it gas-tight. In the
one-day initial phase that starts immediately, fresh air
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Biogas was previously processed where the biogas CHP at the waste digestion plant is now located.
The flare used to burn off lean landfill gas today was used during that period as well (at right).
introduced though nozzles in the floor of
the concrete container in the fermenting
chamber brings about aerobic heating in
the biowaste – even in the winter. While
the wall and floor heating systems maintain
the thermophilic process temperature, the
fermentation material is then inoculated
with microorganisms through continuous
wetting with cell fluid (percolation liquid)
that is discharged during fermentation.
The percolation liquid is generated by previous
fermentation processes in this and
four other digesters. A drainage system
is used to collect it in a percolate storage
tank (capacity of 600 cubic metres) and is
reused to continue to moisten the fermentation
material. This circulation system
enriches the percolation liquid continuously
with the organic acids required for
the methanation phase.
Biogas from the percolate
storage tank
“Biogas with a high methane content is
continuously produced in the percolate
storage tank,” says Raupach. But biogas
is produced in the five digesters as well.
Because they are operated on a staggered
schedule (batch operation), both
the amount of biogas produced and the
me thane content fluctuate accordingly.
The double membrane gas container on
the roof of the plant with an absorption
capacity of 800 cubic metres keeps the
level consistent. The biogas produced in
the percolate storage tank also flows into
the double membrane gas container. The
mixture has a methane content of about 54
percent. Before it is converted to electricity
in a CHP plant with an output capacity of
360 kilowatts, the gas flows through
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English Issue
Biogas Journal
| Autumn_2020
Plant manager Ronny Raupach monitors the fermentation
processes on the screens in the control room.
A front loader is used
to bring the biowaste
delivered to the collection
hall into the
five garage-shaped
fermenters without
any further treatment.
A batch procedure is
used.
Compost following the second screening procedure in which
the drum screen has a mesh size of 15 mm.
an activated carbon filter to reduce the sulphur content.
The end of the fermentation process is signalled
by stopping the percolation liquid sprinkling and then
the subsequent draining phase. Before the gates are
opened, the digester must be completely emptied of
gas. To do so, exhaust air with a methane content of
20 percent is fed into the gas tank; all air with a lower
methane content is burned off with a lean gas flare.
While the digester is emptied and then filled again, an
intensive venting of the fermenting chamber is carried
out and the exhaust air is cleaned with acidic scrubbing
using a biofilter.
Container vehicles transport the completely fermented
material to the composting facility on the plateau on
top of the landfill. The treatment of the digestate and
the shredded green waste generated by the maintenance
of parks and open spaces (1,000 tonnes annually)
starts with setting up the organic storage heap in
the first post-rotting area. “The employees for this area
cover the storage heap with the GORE Cover System
by UTV AG with a special foil that functions as a semipermeable
membrane,” says Sylvana Hallmann, manager
of the waste disposal facility, as she describes the
steps of the process. The material then rots for a period
of three weeks, and after it is turned, for another period
of two to three weeks under the foil while temperature
is monitored and ventilation performed, depending on
the process. This first post-rotting phase, during which
hygienisation is also carried out, is followed by an open
composting period of two weeks.
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Biogas Journal | Autumn_2020 English Issue
Drum screen with a mesh size of 50 mm. Almost all of the
impurities are removed in the screening process because
they are not chopped up in the mechanical treatment of the
biowaste before it is fermented.
RAL quality seal for compost is the goal
Before it is marketed, the compost is screened twice.
Almost all of the impurities are removed with the first
drum screen (with a mesh size of 50 mm) because
they are not chopped up in the mechanical treatment
of the biowaste before it is fermented. In the second,
fine screening required before marketing, the mesh
size is 15 mm. “We are currently going through an approval
procedure by the German quality association for
compost (BGK) to receive the RAL quality seal, and
the initial analysis certificates already indicate that we
are meeting the required quality criteria,” emphasises
Hallmann. The compost is used for agricultural purposes
for the most part, but soon it will also be marketed
locally to residents and professional gardeners.
Annually the biowaste digestion plant produces approximately
1.2 million cubic metres of biogas, which
in turn is used to generate more than 2.1 million kWh
of electricity and about 2 million kWh of heat for use
on site and to feed into the municipal grid. There are
definitely supply reserves. “The system consisting of
fermentation and subsequent composting is designed
The coarse and fine screening of the compost following the post-rotting process
is carried out with a mobile drum screen, the Terra select T55 by Eggersmann.
to process up to 16,000 tonnes of biowaste and 2,500
tonnes of green waste,” explains municipal operations
manager Moritz. This means that the city has created
a basis that will ensure the sustainable and environmentally
sound use of the biowaste generated by the
community into the future.
Author
Dipl.-Journ. Wolfgang Rudolph
Freelance Journalist
Rudolph Reportagen - Agriculture,
the Environment, Renewable Energies
Kirchweg 10 · 04651 Bad Lausick, Germany
+49 3 43 45/26 90 40
info@rudolph-reportagen.de
www.rudolph-reportagen.de
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21

English Issue
Biogas Journal
| Autumn_2020
Green on the production line?
The transformation of automobile
production in Germany
The largest German automobile manufacturers are demonstrating their commitment to
lowering CO 2
emissions in vehicle manufacturing. Porsche is turning to biogas as well in
the production of their first fully electric sports car.
By Dipl.-Ing. · Dipl. Journ. Martina Bräsel
About 90 percent of the heat produced is used to supply heat and hot water for the
office and production buildings. Another portion is used as process heat, e.g. here in
the painting department.
By 2050, the German economy is supposed
to be based, for the most part, on CO 2
-neutral
activity. If the automobile manufacturers
do not achieve the climate protection
goals, they face fines and damaged reputations.
The large German vehicle manufacturers are
now starting to implement their plans for lowering CO 2
emissions. According to Daimler CEO Ola Källenius,
by 2039 the entire fleet will operate CO 2
-neutral from
production to operation. The new “Factory 56” at the
Sindelfingen location was planned as a CO 2
-neutral facility
right from the start. Daimler will produce electric
vehicle model EQC with green electricity at the Bremen
facility. Enovos Deutschland and the Norwegian company
Statkraft will supply the “100 % green electricity”.
A majority of the electricity supplied is supposed to
come from German solar, wind, and hydropower plants.
BMW also wants to use only green electricity in its production.
Milan Nedeljkovic, Member of the Board of
Management of BMW AG Production, told the journal
Automobil Produktion that “as of this year we will be
using only electricity generated from renewable sources
in our plants” worldwide. According to a spokesperson,
the annual electrical power consumption of the BMW
factories is about 5.2 million megawatt hours (MWh)
(5.2 billion kilowatt hours).
Eighty percent of the electricity used in the BMW plants
is already today from renewable sources. For example,
the Leipzig location is supplied by wind turbines, a factory
in Mexico has 70,000 square metres of solar modules,
and in South Africa, the manure of 30,000 cows
is used to operate a biogas plant. The BMW plant in
Dingolfing uses only green electricity as well.
The company also has a roof-mounted photovoltaic system
covering 90,000 square metres and it uses combined
heat and power generation (CHP) to generate
electricity and to supply hot water. BMW has invested a
total of 50 million euros in these systems at the Dingolfing
location alone. Altogether, the nine CHP plants save
a remarkable 23,000 tonnes of CO 2
when compared
with separate electricity and heat generation.
Photos: Martina Bräsel
22

Biogas Journal | Autumn_2020 English Issue
CO 2
-neutral production at Porsche
“Porsche has set goals for climate protection as well,”
explains Anke Höller, Head of Environmental and Energy
Management at Porsche, adding: “We are well on
our way and expect to complete our first big steps by
2030”. The first fully electric Porsche has been in production
since September 2019 in the Stuttgart-Zuffenhausen
location. The Taycan is also the first Porsche
that is CO 2
-neutral with respect to production.
Thanks to extensive measures taken to expand and
renovate the headquarters in Stuttgart-Zuffenhausen
and the use of renewable energies, the entire production
site is now climate neutral. Here in Zuffenhausen,
about 150 gigawatt hours (GWh) (150 million kilowatt
hours) of electricity are required annually; the gas demand
is about 180 GWh.
Stephan Hartmann, Energy Manager, reports that “the
most important energy sources are green electricity
and biogas. The amount of oil used for heating is marginal;
it is used for maintenance tasks, for example”.
About 90 percent of the heat produced is used to supply
heat and hot water for the office and production
buildings at the Zuffenhausen location, where about
13,000 people work. Another portion is used as process
heat, e.g. for immersion equipment in the painting
department.
Painting department: Energy consumption
reduced by 30 percent
According to engineer Anke Höller: “In the painting
department we replaced thermal afterburning systems
with a renewable energy system”. This measure reduced
energy consumption in this area by 30 percent.
“We think about energy efficiency in an holistic manner
and, for this reason, we are also looking at processes in
the joining technologies area that protect resources as
well,” she adds.
Since 2017, the company has also been using green
electricity at all of its locations, and since the beginning
of 2018, it has also used electricity from renewable
sources for the train transport of new cars to seaports.
Based on information supplied by Porsche, the company
considers the origins of the electricity it procures.
“Information regarding the electricity and its origin is
collected by a single source. This ensures that both
come from one and the same renewable energy system,”
says Stephan Hartmann.
Biomethane replaces natural gas
In comparison with the CO 2
emission factor for the domestic
consumption of electricity, more than 60,000
tonnes of carbon dioxide emissions are prevented annually
at the Zuffenhausen location. In addition to this
measure, the heat supply will be converted to biogas.
With the two new combined heat and power plants in
Zuffenhausen, Porsche has started down the path to
CO 2
-neutral production for the fully electric Taycan. In
the meantime, the entire requirement for natural gas
is now met by biomethane. This saves another 30,000
tonnes of CO 2
emissions per year at the site.
Two new combined heat and power plants (CHP) supplement
the generation of heat and electricity for which
the company had already been using two CHP plants
operated with natural gas. “These plants were also
converted to biomethane from the market. The new
combined heat and power plants have an overall degree
of efficiency of more than 83 percent,” explains
the Energy Manager. At the moment, the biomethane
is procured from the European market and is produced
exclusively from waste and residual materials. The biomethane
required in Stuttgart is verifiably measured in
the energy generation facilities and fed into the grid.
The equivalent amount is then accounted for at Porsche
as biomethane.
Future biomethane source: municipal
waste facilities
“There are not yet any biogas plants in our direct vicinity
which produce energy from waste,” explains
Höller. Due to the fuel-or-food discussion, using maize
to produce energy has not been considered. According
to Höller, “We have chosen not to use renewable raw
materials in competition with the food market”. Moreover,
most of the German biogas plants are subject to
Germany’s Renewable Energy Act (EEG) and financed
by the production of electricity. “For this reason, there
is little interest in supplying the gas,” she adds. The
residual amounts are too low and too expensive. However,
Porsche has made preparations in Stuttgart to use
bioenergy generated from a new, municipal biowaste
facility in the future. Operation is expected to begin in
2021. And the construction work for the gas pipeline
to the site, which is about three kilometres away, is
already underway.
“We can’t practise climate protection on our own,” explains
Anke Höller. But it is worthwhile to look beyond
the factory fences to find appropriate partners for cooperation.
According to Höller, “When the city
Starting in 2021, a
biogas plant will
provide part of the
energy supply. The
company will use gas
produced by the waste
of Stuttgart residents
to generate about
18.6 GWh.
23

English Issue
Biogas Journal
| Autumn_2020
For Anke Höller, saving energy and reducing consumption are
not inconsistent with cost efficiency. When the legal requirements
are taken into consideration, the price of biogas is indeed
higher, but on the other hand, investment costs are saved.
photo: Martina Bräsel
With the two new combined heat and power plants in
Zuffenhausen, Porsche has started down the path to CO 2
-
neutral production for the fully electric Taycan.
photo: Porsche
been installed in addition to
the existing district heating
network. “Our site is quite
centrally located in the city
and is supplied by two of its
own heating systems,” says
Höller. For this reason, building
additional decentralised
plants is problematic. And
although at first glance it
seems like climate protection
measures are very cost intensive,
they have also proven
worthwhile for the company.
A sensitive location: The Porsche plant in Stuttgart-Zuffenhausen
requires about 150 GWh of electricity per year; the gas
demand is about 180 GWh. The site is quite centrally located
in the city and is supplied by two of its own heating systems.
The construction of the gas pipeline to the site, which is
about three kilometres away, is already underway. The
pipeline will enable the use of bioenergy generated by the
new municipal biogas plant.
of Stuttgart was looking for a customer for
the biogas from the waste disposal facility,
we submitted an application.” The project
got started with the cooperation of the city
of Stuttgart. “However, these types of large
projects require patience,” Höller says.
Stuttgart’s waste disposal unit, Abfallwirtschaft
Stuttgart (AWS), located in north
Zuffenhausen, was planning for a biowaste
fermentation plant as early as 2012. The
Hummelbrunnen site is located about three
kilometres away from Porsche. Approval
with regard to the Federal Immission Control
Act (BImSchG) is now secured and the
submission of tenders for the construction
work is underway. The actual construction
is expected to take a year and a half. In that
case, the plant, which can process 35,000
tonnes of biowaste per year, will be ready for
operation in 2021.
“When the municipal waste facility starts
operation, we will replace some quantity
of biomethane procured from the market
with biogas produced locally,” Hartmann
explains. The company will use gas produced
by the waste of Stuttgart residents
to generate about 18.6 GWh. That is about
10 percent of entire gas needed at this production
site. “A direct pipeline will supply
the gas to two of our combined heat and
power plants”. But this amount is still not
enough to operate both plants all year long.
“Locally produced biogas is a priority for us,
but, if necessary, we will mix it with biogas
from the grid,” says the Energy Manager.
For Anke Höller, saving energy and reducing
consumption are not inconsistent with cost
efficiency. When the legal requirements are
taken into consideration, the price of biogas
is indeed higher, but on the other hand, investment
costs are saved. The department
head explains why: “In the Taycan production,
the primary energy demand for the entire
location decreased by such a large extent
that by procuring biogas, we exceeded
the legal requirements”.
Due to the legal requirements of the Renewable
Energies Heat Act (EEWärmeG),
without biogas, decentralised systems such
as building heat pumps would have to have
photos: Martina Bräsel
Natural gas to be
replaced in Leipzig
“We have developed concepts
with which we can save
money,” concludes the Head
Environmental and Energy
Management. Other locations
will follow the example set in
Stuttgart. “At our Leipzig site
we have been using biomass
right from the beginning,”
says Höller. There about 44
percent of the heat is generated
from wood biomass.
“Right now we are developing
ways to replace the rest of the
natural gas we use there in a
CO 2
-neutral manner,” reveals Höller. Since
2012, Porsche has been part of the Volkswagen
group. The group has clearly defined
its CO 2
targets. Currently, Volkswagen is
converting its energy supply at its headquarters
in Wolfsburg, for example, from coal to
gas. Now the automobile group is replacing
the existing hard coal boilers with several
gas and steam turbine plants that will go
into operation in stages starting in 2021.
This conversion, which cost VW 400 million
euros, will reduce the annual CO 2
emissions
from the world’s largest automobile factory
in Wolfsburg by 1.5 million tonnes. That is
equivalent to the annual CO 2
emissions of
about 870,000 cars.
Author
Dipl.-Ing. · Dipl.-Journ. Martina Bräsel
Freelance Journalist
Hohlgraben 27 · 71701 Schwieberdingen
+49 71 50/9 21 87 72
braesel@mb-saj.de
www.mb-saj.de
24

Biogas Journal | Autumn_2020 English Issue
BIOGAS Convention
International 2020 –
Goes Virtual!
16. 18 –– 2020. November 2020, Hanover, 2020 Germany
08. – 10. Dezember 2020
Between October 8 th and 10 th 2020,
BIOGAS Convention International will
explore the opportunities and challenges
that the worldwide biogas industry will be
facing over the next few years.
Because of Corona, the BIOGAS Convention
has to strike out in a new direction and will
present its 2020 programme virtually in two
parts: The German presentations given by
the BIOGAS Convention will be broadcast
from 16 th – 20 th November 2020. This will be followed
by the English programme with panel discussions at
the BIOGAS Convention International from 8 th – 10 th
December.
BIOGAS Convention International will present two
aspects of biogas and how they interact: One presentation
will be on the “German Biogas Competence”,
which will explain why Germany has become the leader
in biogas technology, despite all the difficulties. The
presentations will show how Germany companies successfully
market their technologies and the issues they
have to struggle with. And the other aspect is of a global
nature: Which projects are being implemented abroad?
How are things developing in other countries? Will the
production of bio-methane become the key to success?
What will be the effects of the EU regulations on fertilizer
products? Will the waste fermentation be able
to solve part of the world’s waste problems? Why
do we need standards in order to establish biogas
successfully in a country? We will discuss
these questions with speakers and participants
from the whole world.
From 16 th – 20 th November, Fachverband
Biogas will present the following topics to all
those interested in the German programme:
German strategies and climate policies, future
projects, laws and regulations. The presentations
will particularly address the requirements
for German plant operators and companies.
All the details on the German programme can be found
on the German pages of www.biogas-convention.com.
There will also be a fair share of intercommunication:
The programme will include exchanging ideas, asking
questions and holding virtual meetings with companies.
There will be a 20 % discount on the regular ticket price
for registrations that are made by 16 th October 2020.
Companies on the DAC list can take part at special
conditions. The programme of the BIOGAS Convention
International 2020 and the ticket shop can be found at
www.biogas-convention.com/en.
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25
WWW.WANGEN.COM

English Issue
Biogas Journal
| Autumn_2020
Tobias and Claudia
Dreher in front of the
charging station.
Charging electric vehicles at
the adventure farm
At their farm, the Drehers have installed a quick-charging station for electric vehicles that
is powered with electricity directly from their biogas plant. Operations Manager Tobias Dreher
feels equipped for the new era of electric drives. “Biomobility” is his answer.
By Christian Dany
It’s a cold, but sunny winter’s day in Lampertsweiler
in Swabia, a region in southern Germany. Tobias
Dreher is sitting in his Tesla. While the car is connected
to the farm’s own charging station, he shows
me the cockpit with its large touchscreen monitor.
“The S model is actually a highly advanced computer
on wheels,” he says, and, indeed, it looks just like that.
Dreher believes the electric revolution in the automotive
world has begun and that it will soon develop into
a massive trend.
Tobias Dreher has a vision: “In a few years, when the
few quick-charging stations in Bad Saulgau can’t keep
up, electric vehicle drivers will travel the few kilometres
to Lampertsweiler and charge their cars at our farm
station”. The village is located between Munich and
Freiburg.
The first German high-power charging
station
Germany’s first high power charging (HPC) station at
a biogas plant was completed last November. HPC
quick-charging stations have a charging capacity of
more than 150 kilowatts (kW). The charging station
has three charging connections: the most powerful, the
CCS, can provide 150 kW of direct current. The CHAdeMO
socket provides 60 kW and the type 2 socket 22
kW. “Not many cars are able to charge at 150 kW yet,”
says the biogas plant operator. “But that’s the advantage
for those of us with biogas plants: we have enough
available capacity. I can feed 1,000 kW of electricity
into our transformer station”. In addition to the biogas
plant with 420 kW el
, at the Dreher farm there are also
photovoltaic (PV) systems with 435 kW el
.
Photo: Tobias Dreher
26

Biogas Journal | Autumn_2020 English Issue
The biogas plant went into operation with less capacity
in 2003. Now, Dreher conducts his pioneering work
towards electromobility. But the 47 year old farmer is
somewhat distressed because his pioneering role is receiving
less recognition this time: “Many of those with
biogas plants shake their heads when I talk about electric
cars”. Recently he was supposed to hold a lecture,
but he declined. As long as there is disagreement about
electromobility in the biogas sector, he prefers to stay
out of the discussion.
The Drehers have three children. Under the management
of his wife Claudia, they also rent out holiday
apartments on the farm. ”Drehers Erlebnishof”
(Dreher’s Adventure Farm) has 18 apartments, some
of them in log cabins. “Children from the city don’t
know anything about modern farming,” says the operations
manager. Children who spent their holidays
in Lampertsweiler learn that almost everything at the
stables, which hold space for 120 dairy cows, is done
automatically with milking and feeding robots. They see
a lot of animals, but also the newest technology – and a
biogas plant. Dreher’s business, which holds about 150
hectares of crop land and 100 hectares of pasture, is
run by four employees.
A flood of E models by 2022
While we enjoy our coffee in the cosy snack area, the
farmer continues: “We have many holiday guests from
the Stuttgart area, including some Daimler and Porsche
employees with whom we always have interesting conversations
about the future of the automobile industry”.
Daimler and VW have announced that they will stop
developing combustion engines. Then he points to an
automotive publication which states that 70 new electric
models will be available by 2022. Electric vehicles
offer many advantages: “They don’t need a transmission,
neither a clutch nor an exhaust”.
Dreher is positive that people with PV systems on their
roofs will also convert to electromobility as soon as the
compensation of the Renewable Energy Act (EEG) runs
out. That will lend even more momentum to the trend
toward electric vehicles. “We have been producing
electricity from biogas for 17 years. That is why I drive
an electric car,” he explains. If energy generated from
biogas is used for transportation, he sees more advantages
in electromobility than hydrogen mobility. Moving
to gas treatment rarely pays off for small and mid-sized
biogas plants operators; storing the electricity directly
in the battery of the electric car is better than using
electricity to produce hydrogen at a poor degree of efficiency.
An electrician who often works at the operation told
Dreher about a company called E-Wald GmbH who had
commissioned the electrician to install a charging station
nearby. For the charging station on his farm, Dreher
then immediately chose the flagship model of the Bavarian
company, the “Hypercharger”.
Photo: Christian Dany
The Tesla is connected to the charging cable. The socket
is hidden below the rear lamp cover.
“I bought the charging station
and had it installed. No more
work required”
Tobias Dreher
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27

English Issue
Biogas Journal
| Autumn_2020
Laying the charging
station cable over the
cow barn.
Its total output capacity of 150
kW can even be expanded to
300 kW. “I bought the charging
station and had it installed.
No more work required,” he explains.
E-Wald is not only the
supplier, it also offers support
service. “If something isn’t
working, I can call the E-Wald
service hotline number which is
posted on the charging station”.
But is investing in a charging
station also a profitable business?
Dreher is quite candid
here and shows me the invoice
from December: The turnover
of the brand new station just
exceeded 100 euros. After deducting
the revenue share and
service fees for E-Wald, the
biogas farmer receives around
57 euro cents per kilowatt hour
(kWh) for the electricity that
customers charged at his farm
station. “And I also have to pay
the EEG surcharge to the grid
operator,” he says.
Customers generally pay for the electricity with charging
cards issued by energy and service providers. There
is now quite a wide selection of cards. E-roaming allows
drivers to charge at a wide range of public charging
stations. Depending on the provider, direct current is
provided for 35 to 50 euro cents per kWh. The reason
that the price does not cover the costs, though, is that
the charging card issuers are still financing the scheme
primarily through the marketing budget. This results in
the odd situation that Dreher benefits from charging his
own vehicle at his own charging station even though the
profits are hair-thin. He knows that: “I won’t be earning
much money from the charging station any time soon.
But I hope to in the long run”.
The hardware for the entire charging station cost
43,600 euros net. At 36,600 euros, the installation
was more expensive than average: It was difficult to
lay the cable over the roof of the cow barn. Plus, the
transformer station had to be modified.
Federal subsidies for the investment costs
Dreher was granted a subsidy that covered 30 percent
of the investment expenses (which is in accordance
with the funding guidelines for the charging infrastructure
for electric vehicles issued by the Federal Ministry
of Transport (BMVI)),granted that the charging station
is accessible day and night and that the electricity
is generated from renewable sources. Subsidies in
amounts greater than 30 percent are available in high
demand areas.
Dreher’s biogas plant has two identical CHPs, each of
which produces 210 kW el
so that enough electricity is
generated even if an engine stops. This ensures that
only electricity produced by biogas is used for charging.
Over the long term, Dreher would like to increase the
amount of this electricity in his farm’s own power supply.
The entire operation uses 200,000 kWh per year,
of which 120,000 are spent for the biogas plant. That
is why Dreher built another photovoltaic system that
generates 86 kW el
last year and added a battery than
stores up to 80 kWh. Part of the PV system is mounted
on the roof of the charging station.
Thanks to the roof and everything else, the farm station
is actually a super rest stop. There is a bathroom that
is always open, and while charging their car, custom-
Photo: Christian Dany
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Planning, Construction, Start-up, Operation, Service
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www.envitec-biogas.com

Biogas Journal | Autumn_2020 English Issue
ers can shop in the farm store or the milk house, buy
dairy products or have a coffee. Children can watch the
farm ducks, chickens, cats, rabbits, ponies, goats and
donkeys. There is even a roe deer doe named Heidi who
grazes with a herd of the sheep. You can also take a
stroll to the biogas plant and the barn and learn how
energy is produced.
Heat network supplies 80 households
Cattle manure makes up about 40 percent of the raw
material used. Although Dreher has direct marketing
for the electricity produced by the two CHPs, he does
not have a flexible timetable. With the expansion, the
plant was given a new commissioning date, so the operating
incentives offered by the Renewable Energy Act
(EEG) are ensured until 2025. But selling heat also
generates income from the plant: A heat grid was built
in Lampertsweiler in 2008 and now 80 households
are connected to it – the majority of the 300 village
residents. A wood chip based heating plant also feeds
heat into the grid, so in 2010, Lampertsweiler became
the first bioenergy village in the district of Sigmaringen
(this requires that at least 50 % of the energy used is
generated locally from renewable sources).
According to Dreher, sustainability plays an increasing
role for their adventure farm as well. This means that
the farm’s energy supply and provisions for sustainable
mobility are important: “We could have an electric vehicle
available for holiday guests to rent,” he says. A
vehicle could also be used by the villagers on a car sharing
basis. In addition, it would make sense to operate
farm machinery, equipment and vehicles with their own
green electricity.
He already has e-bikes for the guests and an electric
mini-transporter, and he’s already looking into the investment
of an electrically operated telescopic handler.
The web address akKuhladen.de (a pun on the
German words for cow battery charging) was recently
registered;the charging station is included in the most
popular charging station apps now. “I haven’t done any
advertising yet. Haven’t even put up a sign,” he says.
And still, there are already drivers of electric vehicles
who have found their way to Dreher’s new charging station.
For more information see: www.drehers-erlebnishof.de
Author
Christian Dany
Freelance Journalist
Gablonzer Str. 21 · 86807 Buchloe
+49 82 41/911 403
christian.dany@web.de
Batteries for the new
photovoltaic system.
HEAVY-DUTY
MIXERS

English Issue
Biogas Journal
| Autumn_2020
Graphical illustration
of the combined
biomethane electric
drive in a bus.
Combined drive:
gas and electric power
New business models are essential for the future of biogas plants in Germany. Now,
CM Fluids AG has developed an interesting perspective. The company wants to make
municipal companies climate neutral by using liquefied biogas. Biogas plant operators
should play an important role in this.
By Rouven Zietz
Only a few years ago, Dr. Hans Friedmann
regularly commuted professionally between
Berlin and his home near Munich.
While he was driving on the motorway, he
realized that he only needed his car’s powerful
engine to accelerate. “On average, I drive much
slower,” he states. That gave him the idea that is now
almost ready to be put on the market. The basic principle:
A small gas engine is installed in a car. A generator,
a small battery and an electrical axis are attached to it
so that the engine can do its job with extreme efficiency.
That is the basic idea.
However, Friedmann and his meanwhile team of five
others, who operate under the name of CM Fluids AG,
are not concentrating on private passenger cars, but
rather on municipal companies that run refuse collection
vehicles and buses, meaning vehicles that continually
have to stop and go. After many years of tinkering,
planning and organizing, the first converted passenger
bus is ready to be put to its first practical test at Munich
Airport. If corona allows, the project will be launched in
the course of the year and will make the airport with its
annual number of 53 million passengers more climate
neutral.
To understand why biogas will play such a crucial role
in this value chain would mean being familiar with Dr.
Friedmann’s background. 61-year old Friedmann has
been working in the field of biogas for 30 years. He is
the founder and former Chairman of Agraferm Technologies
AG. Between 2009 and 2013, he was the Vice
President of Fachverband Biogas e.V. (German Biogas
Association). “Ten years ago, we gave considerable
thought to how biogas plant operators could set up a
business model once the EEG remuneration ran out,”
said Friedmann thinking back.
The idea of liquifying biogas
Back then, he looked for a way of using biogas as a material.
In 2013, he got the idea of liquefying biogas in a
way that would enable it to be stored and transported.
Most of the plants in Germany are not connected to the
gas grid. A positive side effect of this is that CO 2
can
photo: Friedmann
30

Biogas Journal | Autumn_2020 English Issue
be separated in the liquefying process and can be used for other commercial
purposes, such as making synthetic biomethane.
Friedmann himself claimed that he was looking for a solution that could
manage without government support in the long run “to avoid continually
being on the mercy of public policies,” as he calls it. He definitely
wanted to use the biomethane in the transport industry. Even though
his idea was not ripe yet, he founded the company in 2015 with his colleagues
Franz Böhm and Peter Martetschläger.
“Our aim was to attract other investors to a transportation project in
the field of biogas, although we didn’t know yet how that would work. I
received a lot of skeptical feedback from many sources. Some people
had bad experience with investments in the field of biogas, others no
longer believed in the future of the technology,” Friedmann reminisced.
Friedmann and his partners became rather frustrated by all that and
were on the verge of giving up and throwing in the towel when in February
2018, Friedmann discovered an article by Korbinian Nachtmann in the
Biogas Journal. He had written a thesis on the liquefaction of biogas and
presented extracts of it in the Biogas Journal.
Retrofitting a passenger bus
at Munich Airport
Friedmann contacted the author and specialist, who now works at Munich
Airport as an energy manager and discussed his business idea with
him. It led to the idea of retrofitting some of the buses at Munich Airport
and running them on liquefied biogas. The Fraunhofer Institute had
already secured a patent on the energy-efficient drive system. CM Fluids
in turn was granted an exclusive license to use by the research institute
and went on to develop the concept into a marketable commodity. After
lengthy negotiations, the first of the biogas-powered passenger buses is
on the verge of being used at Munich Airport. “We are currently in the
process of optimizing bus control and refining the appearance before
operation actually starts,” said Friedmann.
The business model of CM Fluids AG consists of two sections. Firstly,
retrofitting buses and garbage trucks for environmentally friendly transport
and secondly, supplying the retrofitted vehicles with biomethane –
produced by local biogas
plants. The company
has already progressed
well with retrofitting the
vehicles. There are development
partners who
are prepared to convert
even more of them process-optimizedy
and efficiently.
Construction of the first
pilot plant to liquefy the
biomethane is pending.
“The next step will be
“We want our condenser to be
used by the most interesting
biogas plants in Germany. From
our point of view, that are the
500 kW plants”
to finance a condenser. We have a biogas plant on which we can construct
the pilot plant. We expect that we will need 3 to 4 million Euros
to construct the condenser and optimize the technology,” Friedmann
explained.
Friedmann and his team want to develop their own condenser for future
demands. There are already companies in France and Italy that offer
units like that, but not large enough for the size that Friedmann needs.
“We want our condenser to be used by the most interesting biogas
Dr. Hans Friedmann
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31

English Issue
Biogas Journal
| Autumn_2020
plants in Germany. From our point of view, that are the
500 kW plants. So, we have to be able to liquefy about
250 cubic meters of gas per hour. For this, there is
nothing suitable available on the market. We have to
assemble and adapt it from the available technology
ourselves”.
The prototype of a condenser will be set up on a 500
kW plant near Hof. The financing will be concluded by
summer and the first condenser will be ready for operation
by late 2021. So much for the initial situation. But
what exactly are the benefits for municipal companies?
Friedmann’s answer to that is clear: “An existing bus
will be retrofitted for a municipal transport company at
a price that does not cost more than 20 percent more
than buying a new diesel bus. The company will still
keep the old bus in the vehicle fleet, but will then only
need half the amount of fuel”.
As already mentioned, Munich Airport provided Friedmann
with a passenger bus for initial test runs. CM
Fluids AG upgraded the bus at its own expenses. “We
are leasing the bus for one year to the airport. The
airport company will then test the bus on site,” said
Friedmann. 35,000 buses are currently running in local
short-distance traffic in Germany. They consume
around 730 million liters of diesel per year. CM Fluids
is promoting conversion of the generator-electric drive,
CMF Drive, as an alternative to buying new buses,
which could extend the service life of each vehicle in
the fleet by twelve years. Their model will combine the
long range of a combustion engine with the advantages
of an electric drive.
Installation of a lightweight battery
The retrofitting starts by dismantling the engine, the
tank, the drive shaft and the transmission. After that,
an electric drive shaft, for which the electric engines
are already installed in the wheel hubs, is mounted.
Added to that, a battery that needs only 10 to 15 percent
of the capacity and is also lighter is installed. The
engineers also install a small engine-generator unit in
the bus. That is a standard gas engine with a generator.
A methane tank is also integrated in the transport
vehicle. “We use the existing engine compartment and
install the parts we need. We don’t need any additional
installation space for that,” says Friedmann.
As a first step, CM Fluids AG will try to convince the
municipal companies to retrofit their vehicle fleets so
that it can start generating revenue. Next, the biogas
plant operators will get on board. “We want to provide
the biogas plant operators with a finished liquefaction
facility for their operations and buy biogas from the
them at a price that enables them to continue operating
their plants in an economically sound way,” Friedmann
said with foresight.
“We can buy part of the power from the operators for
the liquefaction facility,” he added. “The operators
don’t need any funds and don’t have to make any investments.
We will buy the biomethane from them at a
price that will enable them to continue operating their
plants economically”. For this very ambitious project,
the businessman is still looking for plant operators,
who want to invest in this business model.
Author
Rouven Zietz
Freelance Journalist
Blumenthal 1
86551 Aichach
+49 1 71/24 19 311
twitter.com/rouvenzietz
www.instagram.com/rouvenzietz/
www.schloss-blumenthal.de
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32

Biogas Journal | Autumn_2020 English Issue
Using compost eluate to
“boost” biogas plants
A considerable increase in efficiency due to improved hydrolysis with compost cultures
can be achieved in substrates containing lignocellulose, like straw, grass or maize. The
comparatively simple method of composting under specific conditions can basically rule
out the risk of pathogenic bacteria and also prevents the admission of unwanted heavy
metals or other toxins.
By Dr. Sandra Off, Dipl.-Ing. Birte Mähl, Dipl.-Ing. Dietmar Ramhold
and Prof. Dr. Paul Scherer
According to scientific literature in 1989,
“aerobic” compost material can contain
considerable amounts of micro-organisms
that produce methane (Derikx et al., 1989).
Back then, however, no experiments were
made with compost to increase the output of biogas.
In 2009, the Scherer workgroup started experimenting
with continual monofermentation of fodder beet silage
to show that aqueous compost eluate could increase
(up to 13 percent mesophilic, 40 °C) and speed up the
production of biogas in digesters (Scherer et al. 2009,
2011 https://doi.org/10.2314/GBV:617386501).
This was not only due to inorganic constituents in the
compost. The thermophilic area even saw increases of
up to 27 percent of gas yield (“boosting”). This entailed
first crushing the substrate. Despite the testing done at
that time with gene probes (FISH method) to shed light
on the exact causes, it was still not clear whether Methanogens
or hydrolytically active bacteria had caused
the increase of gas yield.
This issue was to be explored further in the FNR project
“MethaKomp” (FKZ 22413612/22413712) that was
carried out with ISF GmbH (Pinneberg/Wahlstedt) with
straw, grass and maize substrates. The project officially
ran from 2015 to mid-2018. In the process, enriched
or selected mixed cultures out of the unconventional
“aerobic” biotope, that was relatively easy to produce,
had to be used in the biogas process. It was therefore
different to supplementing individual dominant types
of bacteria produced in the biogas plants. This new approach
was similar to “natural leaven bacteria” that is
added to starter culture compounds.
Methodology
First of all, ten trial series with comprehensive screening
of various compost clamps and compost phases
from intensive farms again confirmed the positive effect
of the bacteria with aqueous compost raw eluates,
and also later in the laboratory with micro-organisms
enriched with compost eluate. That fully confirmed the
previous findings.
The methodology that was applied included extensive
chemical analyses (trace elements, fermentation analyses)
in order to rule out any abiotic factors. Moreover,
the compost materials and enrichment media were examined
biochemically (enzyme patterns of esterases,
xylanases and celluloses), microbiologically (quantitative
microscopic fingerprinting, qmf, as a digital cell
counter method) and molecular biologically by means
of the next generation microbiome analyses (Next Generation
Sequencing, NGS).
The established increase in gas yield and the increased
formation of gas due to the untreated compost raw eluate
was successfully preserved in subsequent enrichments
of a compost eluate through one-liter select special
cultures (2.5 liter containers) right up to 18-liter
continuous digester cultures. Furthermore, selected
1-cubic meter straw composting (Nils Engler, Uni Rostock)
was inoculated with a highly promising continuous
digester culture derived from that, which resulted
in the production and examination of a specifically generated
compost raw eluate.
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33

English Issue
Biogas Journal
| Autumn_2020
Figure 1: Kinetic representation of test series 3, 6 and 9 (of a total of 10 test series) showing the increase and
acceleration of biogas products from the biogas production of compost raw eluate generated from that in 1-liter
batch digesters at 40 °C
Absolute gas production from the activated sludge with substrate with and
without the addition of compost eluate (substrate = grass silage)
8.000
7.000
Activated sludge + grass silage (A)
Activated sludge + compost eluate + grass silage (B)
T (A)
Gas production (NmL)
6.000
5.000
4.000
3.000
2.000
Test
3, T (B)
T (A)
Test
6, T (B)
T (A)
1.000
0
0 7 14 21 28 35 42
Test days
Test
9, T (B)
The dotted lines only refer to the activated sludge of the referenced biogas plant with grass substrate (A, 40
°C) occurring at the same times T 1
-T 3
as the parallel testing with compost raw eluate (B, 40 °C).
Table 1: Increased specific biogas yield per gram oTS (grass silage) in 1-liter batch digesters by using diluted compost raw eluate
Test series
Difference between the specific gas outputs of
activated fermentation sludge + compost eluate
and activated fermentation sludge + compost
eluate + grass silage (Norm mL/g oTS)
Increase or decrease of the specific
gas outputs in % caused by adding
compost raw eluate
Increased or decreased time to
reach half maximal gas output from
grass silage caused by compost
eluate
V3 +83 (ultimately 453) +22 % -37 %
V6 +69 (ultimately 502) +16 % -20 %
V9 -16 (ultimately 530) -3 % -20 %
Changed fermentation rates until the half-maximal gas output is reached. The organic matter yielded by the eluate and with that the pseudo increase of gas output
was adjusted by subtracting the specific gas output of the compost raw eluate. According to the calculated empirical formula of grass (C 3,9
H 5,5
O 2,8
N 0.2
S 0.0
) and a
non-fermentable lignin percentage of 17.8 %, 541.7 of norm milliliters (Nml) of biogas/g oTS and 287.1 Nml of methane/g oTS are theoretically possible for grass
with 53.0% methane in the biogas. A gas output of V9 therefore corresponds to 98 %. Test time is usually 42 days at 40 °C.
Figure 1 shows the activities of the aqueous compost
raw eluate taken from three trial series. The corresponding
large-scale composting plants were large-scale
communal operations for green waste and bio-waste.
Findings
The aqueous compost raw eluate in which bacteria is
aggraded as a slurry, leads to a biogas output increase
of 15 to 22 percent and accelerates the formation of
gas by 10 to 40 percent, see table 1. But (a few) tests
were also made with compost raw eluate that did not
lead to an increase or that even produced negative
results. However, these effects never occurred with
enrichments or specific compost eluate, so that they
obviously came from the matrix effects of communal
composting. The number of micro-organisms in the
compost eluate came to 1.4x10 9 to 1.5x10 10 per milliliter
and the cell number of Methanogens reached 1.3
to 3. 8x10 8 per milliliter, which corresponded to about
1/10 of biogas fermentation.
Current findings have shown that the main effect of
the compost eluate is due to the hydrolytic bacteria
and their extremely high enzyme activity. The effect
of the enzymes on FDA (3‘-6‘ Diacetyl-Fluorescein)
34

Biogas Journal | Autumn_2020 English Issue
Figure 2: Changes in microbial types >5 percent (“major players”) of a compost raw eluate out of test series V3 and the
activated fermentation sludge of a referenced biogas plant in the course of additions culminating in a one-liter select culture
and an 18-liter digester culture
Relative occurrence of the
microbial genera in %
90
80
70
60
50
40
30
20
10
0
Taxonomic genera of the straw enrichments from compost eluates and the
biogas reference plant with an occurrence >5 %.
Compost raw eluate Biogas reference plant 1 liter
Batch fermentation
Eluate V3
Reference plant
(+ gras silage)
with V3
(+ gras silage, 68 d)
1 liter select culture
(+ straw)
SC Straw
18 liter Fed-Batch F14 6 liter conti straw
with SC straw
(+ straw, 173d)
F 1
(mesophil, + straw, 518 d)
Thermus
Parvimonas
Methanosaeta
Bacillus
Garciella
Herbivorax
Bacteroides
Herbinix
Acetivibrio
Fermentimonas
Treponema
Ruminofilibacter
Ruminiclostridium
Sedimentibacter
Clostridium
The 6-liter continuous culture with pure straw as a monosubstrate and a saline solution as a “synthetic manure” (Sebastian
Antonczyk, HAW) is a fully independent test series to show how the microbial enrichment depends on the substrate, in this case
on straw and/or lignocellulose.
Table 2: Enzymatic analysis of the applied activated fermentation sludges out of the referenced biogas plant
and the diluted compost raw eluate (Test series 3)
Test FDA Esterase pNPB-Esterase / Lipase Cellulase (CMC) Xylanase (Xylan)
(U/g oTS) (U/g oTS) (U/g oTS) (U/g oTS)
Activated fermentation
sludges (n=4)
136 3,85 2,0 3,8
Compost raw eluate V3 434 (+319 %) 4,2 (+9,1 %) 3,0 (+50,0 %) 5,5 (+44,7 %)
Defined compost raw eluate 11
out of 1m³- straw composter
480 (+353 %) 108,0 (+280,5 %) 0,5 (-75 %) 16,7 (+439 %)
The list also shows the enzyme content of defined 1m³ composting with straw as the main substrate. Percentage changes between
the activated fermentation sludges and the compost eluate are given in brackets behind the eluate values.
that can be used as an artificial substrate for esterases
(Senzyme GmbH) were particularly suggestive of this.
Compared with the reference biogas plant that worked
on cattle slurry and grass silage, there was an average
increase of more than 300 percent of enzyme activity
(esterases, cellulases, xylanases) as opposed to the
large-scale composting plants. The compost eluate out
of the specific straw compost shows the same, see table
2. However, the enzyme activity of the cellulose was
surprisingly lower in this eluate compared with the reference
biogas plant, which did not occur with the other
enzymes, see table 2.
Taking the approach of the compost eluate with an enrichment
of straw as a substrate, the example out of
test series V3 and the resulting “straw select culture”
showed the prevalence of single types of microbes, see
figure 2. To obtain a better overview, types with a share
of

English Issue
Biogas Journal
| Autumn_2020
Longshaft- and
Submersible agitators
determines the volume here as well. Whereas in easily degradable
substrates, for example sugar or fodder beets, we saw up to 25 percent
of Methanogen in the overall population (not shown). With the enrichment,
however, the types came from both a compost eluate and from
the reference biogas plant with grass, see figure 2.
The compost eluate was always applied together with the activated
fermented sludge of a reference biogas plant because this produced
the best increasing effect. This could have been because the examined
compost eluate in the ten test series only showed the types of Methanogens
in a range with a share of 5 percent as “major players”, see figure 2.
When the enrichment was begun, only about 30 percent of the microbial
population of the compost eluate consisted of “major players” and
thus had twice as much biodiversity as the reference biogas plant with
about 65 percent of “major players”. In the “straw select culture”, only
7 types ultimately prevailed, accounting for a total of 80 percent of the
population with an individual proportion of >5 percent.
Thus, a total of eleven types of bacteria ultimately prevailed as “major
players” out of the high biodiversity with hundreds of “minor players”
in combination with the activated fermented sludge of the reference
biogas plant. The fact that this happened due to the straw is shown in
the last column, which shows a similar pattern to the second last one,
but which came from a completely different test with an automated
6-liter continuous straw digestion (agitation reactor) over two years
and was inoculated with completely different activated fermented
sludge (Strohtagung Heiden 2019). But it showed a similar bacterial
pattern with eleven types >5 percent as the “straw select culture” out
of the compost eluate.
Components for Biogas
Authors
Sandra Off (HAW)
Birte Mähl (ISF GmbH)
Dietmar Ramhold (ISF GmbH)
Paul Scherer (HAW)
Progressive Cavity-, Centrifugal-,
Feeding- and Longshaftpumps
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M. Sc. Katarina Wegner (HAW)
Dipl.-Ing. Sebastian Antonczyk (HAW)
Dr.-Ing. Thomas Fritz (ISF GmbH)
Ute Habermann (Senzyme GmbH)
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www.armatec-fts.com
36
HAW = University of Applied Sciences, Hamburg-Bergedorf,
FSP Biomassenutzung Hamburg
ISF = ISF GmbH Schaumann Forschung, Wahlstedt

Biogas Journal | Autumn_2020 English Issue
Vietnam
Lack of overall strategy on the
expansion of biogas production
Biogas technology has been explored and applied in Vietnam since the 1960’s. About
500,000 biogas plants have been constructed in the country to date, but most of them are
small-scale (the capacity less than 50 m 3 ) and do not have any grid connection.
By Ms. Le Thi Thoa
Photo: GIZ
Biogas technology has brought great advantages
to local people to improve their life
quality. For example, biogas plants can
successfully treat the organic fraction of
waste such as crop waste, municipal waste,
sewage sludge etc. When used in a fully engineered
system, biogas technology not only prevents pollution,
it also allows energy, compost and nutrient recovery.
Due to environmental protection and an ambition for
clean energy development, the Government of Vietnam
has recently placed greater focus on biogas technology.
The Government had set up its objectives to 2025 in
the revision of “The National Strategy on Integrated
Management of Solid Waste, with a vision to 2050”.
This strategy is known as Decision No. 491 issued by
the Prime Minister on 7 th May 2018. According to the
decision, 80 % of waste generated from livestock, cattle
and poultry activities and food processing should be
collected, reused or recycled as compost and biogas as
well as treated to meet environmental
protection requirements.
Although the biogas technology in Vietnam
was introduced more than 50 years
ago, the number of large-scale biogas
plants is still limited in terms of quantity.
Only 0.3 % of total installed biogas
plant have a capacity of more than
1,000 m 3 . The current development of
biogas plants is far below the real demand
on organic waste treatment that
has increased significantly.
As a developing country with a strong
agricultural sector, Vietnam has significant
potential in livestock, foodstuff
and municipal solid biowaste to
produce biogas. However, most of the
large-scale biogas projects are just concentrating
on waste water treatment to
meet the Government’s environment
protection requirements. At present,
the most common biogas technologies
in Vietnam are:
a. high-density polyethylene (HDPE) covered
biogas lagoons,
b. plug flow biogas digesters and
c. upflow anaerobic sludge blanket (UASB).
a. HDPE covered biogas lagoon
This is the most common type of biogas technology in
the country at present because of its low cost and because
it is easy to install in terms of time and technology.
It has several variations of design that have been
“imported” from Thailand and some other countries.
As the technology is more economical and more easily
operated than other anaerobic digester systems, in
many provinces it has been installed mainly in livestock
farms, milk and cassava processing plants with 1,000-
50,000 m 3 per lagoon. However, despite its simplicity,
HDPE has several drawbacks such as poor bacteria-tofeedstock
contact with low loading rate and low
In Vietnam, biogas is
used on a small scale
for heating, cooking
and to generate
electricity.
37

English Issue
Biogas Journal
| Autumn_2020
Gastight underground
tanks for the production
of biogas.
methane production due to lower efficiency (less than
60 %) of anaerobic pond system and lack of operation
control.
b. Plug-flow biogas digesters
The plug-flow biogas tank has been designed and distributed
to several breeding farms in Vietnam by the National
Institute of Energy. This type of biogas plant can
scale up to a digester volume of 1,000 m 3 . The plants
were constructed at 20 livestock farms with capacity of
150-500 m 3 in some provinces, which have large-scale
livestock potential. The tank is divided into three units,
which is suitable for the fermentation and producing
biogas period, and therefore, the removal efficiency of
organic substances (COD, BOD 5
…) is quite high, about
75-85 %.
c. Upflow anaerobic sludge blanket
This technology is very popular and is installed on a
large scale in Vietnam. It has been applied at some food
processing factories such as cassava, wine and beverage
ones, but the investment cost is often high. Thousands
of cubic meters of wastewater can be processed a
day while 80-90 % of organic matters can be removed.
Barriers in the development of
biogas projects
Although Vietnam has approved policies on renewable
energy development, green growth, livestock development
strategy, and greenhouse gas (GHG) emission
reduction, there continue to be significant gaps in
policies and regulations, which have not supportet the
electricity generation with biogas technology. These key
barriers are related to (a) technology; (b) legal and regulatory
framework; (c) economic and financial issues and
(d) awareness and capacity.
a. Technological barriers
While proven and high efficiency large scale biogas
technologies have been common in many countries in
the world, they are almost unknown in Vietnam. At present,
no local companies are providing complete modern
biogas plants as well as biogas generators. Most of
the biogas technologies are imported from China, Thailand
and the EU, which has resulted in higher investment
and costs for operation and management (O&M).
Even worse, there are still no regulations for testing and
quality control of the equipment.
Infrastructure such as the availability of feedstock is
also an issue because biogas production mostly comes
from energy crops, livestock farms and processing of
agricultural products, etc. These crops were primarily
cultivated for food and fodder production. For example,
lack of vehicle and inadequate waste transportation increase
the risk of supply chain disruption and create a
barrier for utilizing waste in biogas production.
b. Legal and regulatory framework barriers
At present, there are no concrete, comprehensive policies
for investment, management and operation of biogas
projects. Main legal shortcomings are:
ffNo feed-in tariff (FIT) for biogas electricity: FIT has
not been implemented, although the Government of
Vietnam has announced tariffs for small hydro, wind,
solar and biomass (co-generation) power. As a result,
biogas developers and investors are reluctant to
implement their projects. Without financial support
mechanisms, biogas electricity is unable to compete
with other renewable energy sources.
ffInadequate standards and codes: The lack of technical
codes for the manufacturing, installation and
maintenance of renewable energy technologies is
one of the key barriers for technology transfer of
biogas equipment. The absence of the technical
standards leads to uncontrolled quality variations of
products.
c. Economic and financial barriers
Economic considerations play a major role in the choice
of renewable energy sources, so Vietnam faces the following
economic and financial barriers:
ffHigh operating costs: While with solar and wind energy,
the input resources are stable and free, biogas
plants depend on feedstock and its cost which varies
by years and seasons. This has made up the high
operating cost of biogas electricity projects.
ffNo incentive for credit policy: biogas generators and
relevant equipment require large investment capital
while there are no biogas specific green credit lines
that offer lower interest rates specifically for biogas.
From an international perspective, biogas projects
are considered Clean Development Mechanism projects,
so the incentive scheme is crucial. In Vietnam,
however, banks have not made any loan incentive
policies to support biogas electricity projects.
Photo: GIZ
38

Biogas Journal | Autumn_2020 English Issue
d. Awareness and capacity barriers
Lack of skilled and experienced technicians and workers
to undertake the design, construction and maintenance
of biogas plants is hindering the full dissemination
and adoption of biogas production in Vietnam. In
fact, most of large biogas plants have been constructed
with poor-quality building materials in the country.
The plants are not well operated because they lack the
know-how required to repair and maintain biogas digestion.
Meanwhile, the lack of awareness of the benefits
of biogas technology in the country and the government’s
lack of incentive mechanisms for the sector are
considered to be the main reasons for low use of biogas.
Recommendations for sustainable biogas
development in Vietnam
To encourage developers/investors to install biogas digestion
for reduction greenhouse gas emissions, there
are major recommendation as follows:
on operation and maintenance, as well as to bank
staff on financing biogas plants and procedures for
managing/implementing the credit line created for
support biogas owners.
To support the Vietnamese Government in implementing
the above-mentioned solutions, the
Deutsche Gesellschaft für Internationale Zusammenarbeit
(GIZ) GmbH is partnering with the Ministry
of Industry and Trade to carry out the “Climate
Protection through Sustainable Bioenergy Markets
in Vietnam (BEM)” project. The project aims at improving
the preconditions for a sustainable use of
bioenergy for electricity and heat generation in the
country. The project is funded by the German Federal
Ministry for the Environment, Nature Conservation
and Nuclear Safety (BMU) through the International
Climate Initiative (IKI).
Photo: Ho Thi Lan Huong
1. Development and improvement of policies and
mechanisms
Experience shows that the introduction and success
of any technology, to large extent, is dependent
on the government’s policy framework. Policies
are important because the government is the actor
to enable an environment to mobilize resources and
encourage private investment. Therefore, the Vietnamese
Government should develop supporting
mechanisms for biogas power plants. For example,
besides subsidies or an attractive FIT, the government
should further promote its tax policies (current
tax exemption is shown not to be sufficient),
create investors’ access to green loans and develop
favorable loan mechanisms, including grace periods,
longer timelines and favorable interest rates. The
government can also mobilize capital though Official
Development Assistance (ODA) and/or bilateral foreign
loans as well as develop testing and standards
of biogas technologies to improve the reliability of
biogas technologies.
2. Financing mechanism
A specific funding line needs to be introduced for
biogas power plants, which includes sub-solutions
such as providing easier access to soft loans and
support by local banks, and introducing tax incentives
consisting of reduced import taxes and partial
exemption from value-added tax for biogas equipment.
3. Structural development for stakeholders
The structural development should include the
dissemination and update of policy to maintain
transparency and credibility for attracting potential
domestic investors. Training courses should be
provided to technical staff of biogas power plants
The project will enhance the capacities of relevant
Vietnamese institutions and promote the application
of the state-to-art technologies when implementing
its three action areas: 1. legal and regulatory framework,
2. capacity development and 3. technology
cooperation. In the first area of action, BEM is supporting
the Ministry of Industry and Trade to develop
mechanism to support feed-in tariffs for biomass
(co-generation) and biogas power projects and to facilitate
their development.
Author
Le Thi Thoa
Senior Officer GIZ
Energy Support Programme
Deutsche Gesellschaft für
Internationale Zusammenarbeit (GIZ) GmbH
+84 24-39 41 26 05 Ext. 105
+84 902 163 379
office.energy@giz.de
www.gizenergy.org.vn
Model of a plug-flow
biogas digester system
in Vietnam.
39

English Bio2Watt Biogas Issue Plant.
The plant is situated on
a cattle feedlot in Bronkhorstspruit
and uses the
manure for co-digestion
with other food and agrowaste
material. The plant
processes approximately
120,000 tonnes of fermentation
substrate a year.
Biogas Journal
| Autumn_2020
Biogas in South Africa:
A market waiting to be developed
The South African-German Energy Programme (SAGEN) implemented by GIZ, has been
active in the biogas field since 2013. There are more than 38 commercial biogas projects.
SAGEN firmly believes that the industry is rapidly growing and ready to expand.
By Sayuri Chetty and Malett Balmer
There is a variety of organic materials available
for biogas production through anaerobic
digestion in South Africa. This also
comes in high, steady volumes. Some of the
most common feedstock options include
manure from the livestock sector; residues from the
meat processing industries and abattoirs; agricultural
residues from crop plantations and product processing
(fruits, vegetables and sugarcane); residues from breweries
and wineries; food waste and wastewater sludge.
Studies indicate that biogas has the potential to replace
at least 2,500 – 2,800 MW (megawatt) of dirty
coal-generated grid electricity per annum. 39 of 131
municipal waste water treatment (WWT) plants considered
feasible for biogas projects. Combined, they can
generate approximately 27 MW of electrical power and
30 MW of thermal power daily.
South Africa has a dirty energy sector with 90 % of electricity
generated from coal and electricity tariffs have
skyrocketed, increasing by 300 % in the last ten years.
In addition, in 2007 the country started experiencing
rolling black-outs or “load shedding” whenever the national
utility, Eskom, could not keep up with demand.
The combination of high electricity prices, environmental
considerations and the promising potential from the
biogas sector can be considered as the main drivers
for customers who wish to reduce their dependence on
the grid by supplying all or part of their energy requirements,
provide back-up electricity during black-outs
and save on their electricity bills.
Barriers to market development
South Africa currently has a vertically integrated power
sector, whereby generation and transmission are monopolized
by the state-owned utility Eskom. In some areas,
Eskom sells electricity to municipalities who then
distribute to customers in their supply area. The utility
is currently facing many challenges, some of which include
chronic debt, mismanagement, aging grid infrastructure,
and lack of cost reflective tariffs leading to a
vicious cycle of generation and non-recovery of costs.
In this light, embedded generation is perceived as a
Photo: Makwana 2015, © Bio2Watt
40

Biogas Journal | Autumn_2020 English Issue
Northern Works large
sewage treatment plant:
the CHP containers are
set up.
Photo: Karl Juncker, WEC Projects
threat that exacerbates existing problems of revenue
generation, power quality and grid safety. However,
Eskom is currently looking into establishing a process
for connections to the low voltage grid for small scale
embedded generation (SSEG) installations which will
include biogas plants for own use generation, distribution
and sales of electricity, as outlined above. Currently,
only plants generating less than 1 MW receive a
generation license and the power must be consumed
by the entity developing the project – there is therefore
no scope to sell the power back into the electricity grid
as a source of income. The financial viability of the project
is therefore determined by the potential savings
it can generate and not necessarily by the income it
can generate, although there are indications that the
proposed power sector reforms may open the market for
independent power producers.
Development projects with municipalities are not easy.
Municipalities are governed by laws governing their
procurement processes, namely the Public Finance
and Management Act (PFMA) and the Municipal Finance
and Management Act (MFMA). The main hurdle
presented by the legislation centers on the duration of
contracts that municipalities can enter into, which is a
maximum of three years. Most biogas projects require
a much longer time-frame to make the project viable.
Licensing requirements
Biogas projects traverse the mandate of several national
departments due to the integrated nature of the
technology and intended application of the biogas,
making application for the different licenses required
for a project challenging. To add to the complexity, the
approach to develop or amend legislation to include
biogas has taken a piecemeal approach. Therefore,
there are a number of different elements of legislation
that speak to some element of biogas written by different
authorization entities. SAGEN developed a very
detailed overview of licensing requirements, but due
to the complexity of the topic, it cannot be presented
in detail. As previously mentioned, the majority of operational
biogas plants in South Africa are of commercial
scale. There are several installations on a micro to
small scale at schools and low-income households, but
many of these are no longer operational due to a lack
of community engagement, hiatuses in operation for
e.g. during school holiday periods, poor operation and
maintenance, etc.
Large biogas plant in Bronkhorstspruit
The Bio2Watt plant was the first commercial scale
project that helped put biogas on the map. The development
of the plant took almost seven years to complete,
with construction commencing in July 2014 and
commissioning in April 2015. The massive delay in
the project was primarily due to the unclear legislative
framework at the time – the developer had to go through
the full, lengthy process of obtaining all environmental
authorizations which ended up costing almost R8
million rand to complete in conjunction with obtaining
legal advice.
The plant is situated on a cattle feedlot in Bronkhorstspruit
and uses the manure for co-digestion with other
food and agro-waste material. The plant digests approximately
120,000 tonnes of feedstock a year. In
terms of design capacity, the plant is 4.6 MW and has a
10-year offtake agreement to wheel power between the
municipal utility’s grid i.e. the City of Tshwane to the
BMW Rosslyn plant, located 60 km away.
The total project amounted to R150 million, which included
a blended finance approach of R16 million in
grant funding from the Department of Trade, In-
41

English Issue
Biogas Journal
| Autumn_2020
Large Sewage Treatment
Plant Northern
Works: The 1.2 MW
plant was one of the
first of its kind to be
built and was put into
operation in 2012.
Northern Works is the
largest sewage treatment
plant in operation
in Johanesburg.
Photo: Karl Juncker, WEC Projects
dustry and Economic Development, R36 million equity
and a R98 million loan from the Industrial Development
Corporation (IDC). Around half of the materials
and components used for the project were sourced locally,
and some of the major components were imported
from Europe
Large sewage treatment plant produces
Biogas
Example two: Large sewage treatment plant Northern
Works WWTW, Johannesburg. Operational since August
2012, the 1.2 MW plant was also the first of its kind to
be built. Northern Works is the largest WWTW servicing
Johannesburg and the biogas produced displaces 10-
15 % of grid electricity that would be required. There
are plans to install three more CHP engines, which
would then boost the installed capacity to 4.5 MW, providing
more than half of the plant’s electricity needs.
Unfortunately, however, the plant is currently running
under capacity at only 20 % of its potential. This is
largely due to the over-design of the plant, and design of
the contractual arrangement between the operators of
the biogas facility and the water service provider, which
have different mandates and have not practiced holistic
sludge management along the entire sludge train
to ensure that enough sludge reaches the digesters for
biogas production.
There are many other innovative biogas plants installed
in South Africa, for example at abattoirs, cheese farms,
dairies and fruit processing plants. However, the two examples
mentioned above were pioneers in their respective
categories. They have paid the proverbial school
fees, and as a result, have played an integral role in
developing the biogas sector and providing future projects
with valuable lessons learnt.
Conclusion
In comparison with other countries, the biogas industry
in South Africa is relatively small and while it has
been operating at low intensity for many years now, it
is a testament to the industry’s resilience. The South
African German Energy Programme (SAGEN) under GIZ
put great focus on biogas during the first and second
phase of the programme (2011-2013; 2014-2017).
The main focal areas included working towards enabling
framework conditions for biogas. This included
completing resource assessments for different types of
feedstocks and assessing the biogas potential, training
and awareness raising initiatives including creating a
space for dialogue in the form of the National Biogas
Platform (a roundtable for all relevant stakeholders in
the space), and study tours for national and local government
stakeholders to Germany. SAGEN’s products
and outputs can be found at www.sagen.co.za
Authors
Sayuri Chetty
Advisor Renewable Energies
South African-German Energy Programm (SAGEN)
Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH
+27 12 423 5600
sagen@giz.de
www.sagen.org.za
Marlett Balmer
Senior Energy Advisor
South African-German Energy Programm (SAGEN)
Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH
P.O. Box 13732 · Hatfield 0028
Hatfield Gardens · Block C 2nd Floor
333 Grosvenor Street · 0083 Hatfield Pretoria
South Africa
+27 12 423 5981
marlett.balmer@giz.de
www.sagen.org.za
42

Biogas Journal | Autumn_2020 English Issue
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