KNX Journal 2011-1

KNX Projects
Tab. 2. Equipment and control – before/after
Characteristic Before installing Synco living After installing Synco living
Boiler control
Flow temperature control based on Load-based modulation of furnace
outside temperature and reference room
(living room)
Heaters
Thermostatic valves (manual control).
No time schedules.
Eletronic single-room controllers.
Comfortable temperatures based on
times of use.
Heating Continuous Based on occupancy
RF-controlled outlets N/A Timed switching of standby devices;
with occupancy control since
November 2008
Tab. 3. Annual heating consumption values for room heating, electricity and primary energy over time
Period
Degree
day
value
20/15
Natural
gas, standardized
without
DHW
Synco living installation clearly
exceeds the stipulated savings
potential, which in other field
studies was determined to
be 15 – 20 % of the heating
consumption when using
electronic single-room control
systems in residential applications.
The savings would have
been even higher if it had not
been for the extraordinarily
Primary
energy
Relative consumption
Heating
Electricity
Electricity
Kd/a kWh/m² kWh/m² kWh/m² % % %
2004/05 3.501 110 25 187
2005/06 3.852 119 26 201
100 100 100
Primary
Explanation
Before Synco
living
Before Synco
living
2006/07 2.712 99 24 175 87 96 90 Switchover
2007/08 3.420 76 24 148
2008/09 3.415 93 22 161
74 90 80
After Synco
living
After Synco
living
DHW = domestic hot water
Primary energy coefficient, heating 1,1 Primary energy coefficient, electr. 2,7
Specific primary energy = 1.1 * specific nat. gas consumption without DHW + 2.7 * specific elect. consumption
MW
without 114,3 25,3 193,9
MW with 84,3 22,8 154,2
cold months of January and
February during the 2008/2009
heating season. In addition, the
waste heat produced by electrical
devices (used sparingly)
did not contribute to room
heating during the last heating
period under observation. This
effect corresponds to an increase
in natural gas consumption
by approximately 250 kWh/a.
Cost savings
Since installing the Synco living
system two and a half years
ago, the Radetzky family has
been able to save approximately
EUR 400 per year.
In addition, they were able to
reduce their carbon footprint
by approximately 1.5 tons of
CO 2
per year. Since natural
gas and electricity rates in
Berlin are relatively modest
(electricity = EUR 0.174/
kWh, natural gas = EUR 0.058/
kWh), Synco living would
have yielded even higher
cost savings in another city.
In light of these benefits, the
initial investment pays for
itself quite quickly: Based on
2008/2009 energy rates, the
payback period is around six
years. Installed by a specialized
company, a solution such as
the one used by the Radetzkys
costs approximately EUR
2,500. 80% of the costs are for
the heating control devices,
the rest for radio-frequency
switches and socket adapters.
However, homeowners with
basic technical skills are able
to install a standard system
themselves thanks to the
system’s plug & play design.
In this case, the price for a
basic Synco living package is
approximately EUR 950 for
an average apartment.
Summary and future
plans
To counteract the insufficient
thermal insulation of their
apartment in an old building
in Berlin, the Radetzky family
installed a Synco living home
automation system from
Siemens. The result: energy
savings of approximately EUR
400 per year. In the coming
year, Thomas Radetzky plans
to expand his Synco living
system by adding smoke
detectors, door and window
contacts, and a video-based
intruder alarm system.
Contact:
jonathan.copley@siemens.com
Analyse synco living D39
Electricity kWh/m 2
Gas kWh/m 2
Primary kWh/m 2
GTZ 20/15
special energy consumption kWh/m 2
with synco living
Heating period
Picture 3. The control units of the Synco living home automation system
regulate the indoor climate and record the use of energy and water.
Figure 4. Electricity and natural gas consumption as well as primary energy
consumption over time, standardized by heating degree days, heating degree
values of 20/15 for Berlin-Tempelhof.
Journal 1/2011
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