Residential Fuel Cell Micro Cogeneration – Opportunities and
Challenges in the System Design
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Annual oper.
Time (h)
Full load
equiv. (h)
5350
8760
880
610
600
1120
650
Share of
demand (%)
8760
Heat prod.
(kWh/year)
5350
Share of
demand (%)
8760
Elec prod.
(kWh/year)
0.1
Base Load 1
535
11
1076
6
Base Load 22
1070
21
2140
13
0.2
1
7 )*+
Max power
CHP (kW)
"
3
Load Following
4675
94
9350
55
5.3
Peak Shaving
>2 kWe
2000
40
4000
24
3.3 3
Peak Shaving
>1 kWe
2850
57
5700
34
4.3
3
1
Based on all time lowest 24 hours demand (=night)
Twice the base load during daytime compared to Base Load 1
3
More peak power is presumably needed; calculations are made on an hourly basis
Elec. prod. Inhouse use
(kWh/year )
Share of
demand (%)
Heat prod.
(kWh/year )
Share of
demand (%)
23072
2238
45
9090
53
8500
2
Load
following
5175
3325
67
17000
100
Full load equiv.
time (h)
Elec. export to
grid (kWh/year))
4545
Actual oper.
time (h)
Elec. prod.
(kWh/year)
Base Load
Max power CHP
(kW)
Strategy
2
1.0
8760
4545
8760
2575
3.3
1
More peak power is presumably needed; calculations are made on an hourly basis
If a sophisticated predictive control/algorithm is available, some of the heat production might be moved even more to
release less electricity for export.
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Denmark
Finland
Netherlands
Latvia
Czech Republic
Hungary
Germany
Turkey
Slovakia
Poland
Japan
Portugal
Austria
India
Canada
South Africa
Estonia
WORLD
Chile
China
South Korea
Lithuania
Mexico
Uruguay
Luxembourg
Greece
Spain
Belgium
Italy
UK
Sweden
Slovenia
Indonesia
Uganda
Australia
France
US
Thailand
Brazil
Ireland
Argentina
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LT-PEM
HT-PEM
SOFC
Electric output
(net)
1.5 KWe
1.0 KWe
1.0 KWe
Fuel efficiencies
Electric efficiency
(H2 – electricity)
Electric efficiency
(N-gas – electricity)
Electric efficiency
(N-gas – electricity)
Phase 2: 45 %
Phase 2: 35 %
Phase 2: 33 %
Overall electric and
heat efficiencies (H2)
Overall electric and
heat efficiencies
(Natural gas)
Overall electric and
heat efficiencies
(Natural gas)
Phase 2: 80 %
+ 10 % by
condensing
operation
Phase 2: 75–80 %
+ 10 % by
condensing
operation
Phase 2: 80 %
+ 10 % by
condensing
operation
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