Power to Gas

Experiences and Results from the RWE
Power-to-Gas-Projekt at Niederaußem site
Dr. Thorsten Liese
POR-AV
RWE Power AG
AGCS, München 2013
RWE Power AG • Liese 07.11.2013 SEITE 1

utilization options for surplus Power from renewable
sources enabled by Power-to-Gas
Excess Power
from RE
Water Electrolysis is the key technology
of „Power to Gas“ and enables access to
many paths of application
Elektrolysis
Methanisation
Hydrogen
Storage
Gas grid
Power
generation
Hydrogen
Mobility
Industrial
usage
Power
generation
CNG
mobility
Heat market
Industrial
usage
Gasmotor/
Fuel cell
GuD/BHKW
RWE Power AG • Liese SEITE 2

„Power-to-Gas“ – Power Storage as natural gas
PtG stands for the largest capacities of all power storage technologies
> Storage technologies differ in
the storage capacity
> flywheel, battery and pumped
water pumped
storage/compressed air power
station offer low storage
capacity
> Unique feature of „Power-to-
Gas“ is a large storage capacity
> „Power-to-Gas“ connects power
and gas grid
> Gas grid and gas storage
capacity high storage capacity
available
RWE Power AG • Liese SEITE 3

Efficiency of energy storage via Power-to-Gas
Power-to-H 2 -to-Power
100%
80%
60%
40%
20%
0%
100%
80%
60%
40%
20%
0%
100%
100%
95%
95%
Stromnetz
95%-100%
Power-to-SNG-to-Power
Stromnetz
95%-100%
80%
62%
Elektrolyse
65%-80%
80%
62%
Elektrolyse
65%-80%
68%
49%
Methanisierung
80%-85%
76%
52%
Kompression
85%-95%
65%
42%
Kompression
85%-95%
Max
Min
42%
18%
Verstromung
35%-55%
Max
Min
39%
17%
Verstromung
40%-60%
Wirkungsgrag
Wirkungsgrag
RWE Power AG • Liese SEITE 4

Power to Gas – Technical basics of PtG
Elektrolysis
Methanation
RWE Power AG • Liese SEITE 5

Electrolysis – key technology
Atmospheric Alkaline
Pressurized Alkaline
Membrane-Elektrolysis (PEM)
electrolysis
electrolysis
- Power: Ø4,5 kWh el /Nm 3 H 2 - Power: Ø4,5 kWh el /Nm 3 H 2 - Power: Ø4,5 kWh el /Nm 3 H 2
- Pressure:
- Pressure: 30-50 bar - Pressure: 50 bar
atmospheric
- Temperature: 60-80°C - Temperature: 80°C
- Temperature: 60-80°C
> costs 2011 ~1.200-1.600 €/kW el > costs 2011 ~ > 5.000 €/kW el
> costs 2011 ~ 800-1.000 €/kW el
> In industrial range proven
> In industrial range proven > Not industrial range proven
technology
technology
technology
> Module size > 2 MW el
> turndown up to 20%
> Operational Parameter
> Module size > 3 MW el
> turndown up to 10%
> Operational Parameter
> Module size up to 300 kW el
> Turndown up to 0%
> Operational Parameter
Ziel
Elektrolysis is a proven technology
commercial scale electrolysers designed for maximum production
Electrolysers not proven for flexible operation regarding reliable operation,
degradation R&D demand
RWE Power AG • Liese SEITE 6

Methanisation plant – key technology
Plant capacity 150 tm3/h SNG (power consumption 24 TWh/a)
Cost estimation 100-180 Mio € (Based on simulation, sized Equipments, (costs for Piping, instrumentisation,
engineering, labour costs , insurance, freight etc.) considered factorized approach)
RWE Power AG • Liese SEITE 7

Power to Gas – test setup in Niederaußem
RWE Power AG • Liese SEITE 8

Power-to-Gas bei RWE Power
Standort Niederaußem
PEM-Elektrolyse *
KAT-Teststand
Strom H 2 Methanol
Methan
PCC-Anlage **
CO 2
Synthese-Reaktionen
CO 2 + 3 H 2
CH 3 OH + H 2 O
CO 2 + 4 H 2 CH 4 + 2 H 2 O
*PEM-Elektrolyse von Siemens, BMBF-Projekt CO2RRECT
**PCC-Pilot-Anlage, BMWi-Projekt
objective
Catalytic tests of methanisation of carbon dioxide captured
from flue gas with hydrogen
> Catalysts designed for methanisation of syngas (CO + H2) shall be tested for methanisation of
carbon dioxide from flue gases with hydrogen
– Can coomercial available catalysts be used for this kind of application?
– Can CO2 captured from flue gases used for methanisation?
> As an alternative path production of methanol from CO2 and H2 will be tested
RWE Power AG • Liese SEITE 9

Catalyst test set up at Niederaußem site
> Catalyst ttesting of comercial
available methanisation and
methanol synthesis catalysts
> Test set up in container
> Test campaign scheduled until Q1/
2014
> H 2 -Supply: 5 Nm³/h
from gas supply or Elektrolysis
> CO 2 -supply: 2 Nm³/h
from PCC Pilot plant
> Operation at 20 to 30 bar
> Temperatures depending on
Product (Methanol/Methane)
between 250°C and 640°C
> Reactors for1,5 l of catalyst
RWE Power AG • Liese SEITE 10

Power to Gas – simplified Process flow diagramm
RWE Power AG • Liese SEITE 11

Power to Gas – first results
100
100
X CO2 ,experimentell /X CO 2
,Gleichgewicht / %
95
90
85
80
75
X CO2
/ %
70
0
2000 4000 6000 8000
0 5 10 15 20 25
GHSV / h -1 TOS / Tage
80
60
40
20
RWE Power AG • Liese SEITE 12

Power to Gas – first results
100
80
mit Schutzreaktor
ohne Schutzreaktor
X CO2
/ %
60
40
20
0
30 35 75 80 85
TOS / Tage
RWE Power AG • Liese SEITE 13

Power to Gas – PtG test setup Niederaußem
RWE Power AG • Liese SEITE 14

Power to Gas – economic feasibility
RWE Power AG • Liese SEITE 15

Costs for Power-to-Gas
Elektrolysis, Methanisation and power production
Power
production
RE-
Surplus
RE-infeed
demand
time
methanation
η ≈ 80 – 85 %
ex. Gas power
plant
CO 2
power
grid
RE-Surplus
free of charge
Hydrogen
(H 2 )
SNG
gas grid
power
Power
grid
electrolyser
spec. invest
1.200 €/kW Einspeiseleistung
assumed efficiency about 65%
− Assumption: Invest 1.200€/kW, Efficiency about 35%
− Result: Power Production costs >. 50 ct/kWh*, equivalent to 12 times of power
price at stock(4 ct/kWh)
RWE Power AG • Liese SEITE 16
* costs for storage and infrastructure not considered

„Power-to-Gas“ – Power storage as SNG in gas
grid
Power consumption in Germany:
500-600 TWh el/a.
Capacity of natural gas storage facilities in Germany: 200 TWh th. (19 Mrd Nm3)
Gas consumption in Germany:
95 Mrd Nm3 (1.000 TWh th./a)
Power demand to fill german gas storages via PtG:
Power demand to produce german gas demand via PtG:
Power Production in Germany 2013 (Wind PV):
Estimated RE Excess power according scenario 2050:
312 TWh el.
1.550 TWh el.
74 TWh el.
50 TWh el.
50 TWH el. Power converted to gas would be sufficient to supply Germany
for 11 days
RWE Power AG • Liese SEITE 17

Thank you very much for your attention!
RWE Power AG • Liese 07.11.2013 SEITE 18