The system proposed is based on SOFC combined with an air source heat pump (ASHP): exhausted gases of SOFC are mixed with inlet air of heat pump to increase efficiency in particular when evaporator may freeze.

1. ANALYSIS OF A COGENERATION
SYSTEM BASED ON SOLID OXIDE FUEL
CELLAND AIR SOURCE HEAT PUMP
WITH NOVEL HEAT RECOVERY
Giulio Vialetto, Marco Noro and Masoud Rokni

2. Analysis of a cogeneration system based on solid oxide fuel cell and air source heat pump with novel heat recovery
(Vialetto G., Noro M. and Rokni M.)
OVERVIEW MODEL ANALYSIS CONCLUSIONSIMULATION
SOFC (solid oxide fuel
cell) waste gases has a
high percentage of
water (steam). If not
only sensible but also
latent heat could be
recovered, energy
efficiency of the system
could be increased.

3. Analysis of a cogeneration system based on solid oxide fuel cell and air source heat pump with novel heat recovery
(Vialetto G., Noro M. and Rokni M.)
OVERVIEW MODEL ANALYSIS CONCLUSIONSIMULATION
Air source heat
pumps (ASHP) are
cheaper than ground
source heat pumps
(GSHP). In some
climates, however,
evaporation section
may frozen.

4. OVERVIEW MODEL ANALYSIS CONCLUSIONSIMULATION
Analysis of a cogeneration system based on solid oxide fuel cell and air source heat pump with novel heat recovery
(Vialetto G., Noro M. and Rokni M.)
SOFC waste gases are mixed with inlet air into
an adiabatic mixer, increasing both temperature
and absolute humidity.

5. OVERVIEW MODEL ANALYSIS CONCLUSIONSIMULATION
Analysis of a cogeneration system based on solid oxide fuel cell and air source heat pump with novel heat recovery
(Vialetto G., Noro M. and Rokni M.)
The aim is to increase COP of ASHP and
decrease the freezing of evaporation section.

6. OVERVIEW MODEL ANALYSIS CONCLUSIONSIMULATION
Analysis of a cogeneration system based on solid oxide fuel cell and air source heat pump with novel heat recovery
(Vialetto G., Noro M. and Rokni M.)
A traditional heat pump is simulated, a frost factor is
consider in the cases of outdoor air temperature
between –10 to 10 °C and relative humidity between 50-
100 %.

7. OVERVIEW MODEL ANALYSIS CONCLUSIONSIMULATION
Analysis of a cogeneration system based on solid oxide fuel cell and air source heat pump with novel heat recovery
(Vialetto G., Noro M. and Rokni M.)
Simulations were performed with a SOFC of 50
kW nominal power and an ASHP 7.7 heating
nominal power. Temperature varies from –7.5 °C
to 15 °C, relative humidity from 25% to 100%.
Two benchmarks are defined to evaluate the
performances: COP variation and %PES

8. OVERVIEW MODEL ANALYSIS CONCLUSIONSIMULATION
Analysis of a cogeneration system based on solid oxide fuel cell and air source heat pump with novel heat recovery
(Vialetto G., Noro M. and Rokni M.)
COP variation verifies if COP of system
proposed is higher than a traditional ASHP
%PES verifies which is the primary energy
saving of the innovative system compared with a
traditional one.
𝐶𝑂𝑃𝑣𝑎𝑟𝑖𝑎𝑡𝑖𝑜𝑛 =
𝐶𝑂𝑃𝑖𝑛𝑛𝑜𝑣 ,𝑠𝑦𝑠
𝐶𝑂𝑃𝑡𝑟𝑎𝑑 ,𝑠𝑦𝑠
− 1 ∙ 100
%𝑃𝐸𝑆 = 1 −
𝑃𝐸𝑖𝑛𝑛𝑜 ,𝑠𝑦𝑠
𝑃𝐸𝑡𝑟𝑎𝑑 ,𝑠𝑦𝑠
∙ 100 = 1 −
𝐸𝑎𝑣𝑎
𝜂 𝑒𝑙𝑒
+
𝐻𝑎𝑣𝑎
𝜂 𝑏𝑜𝑖𝑙𝑒𝑟
𝐹𝑆𝑂𝐹𝐶
∙ 100

9. OVERVIEW MODEL ANALYSIS CONCLUSIONSIMULATION
Analysis of a cogeneration system based on solid oxide fuel cell and air source heat pump with novel heat recovery
(Vialetto G., Noro M. and Rokni M.)
COP in function of external air temperature (T2) in the
two cases (air relative humidity - SOFC nominal
electric power). Case 1: 25 % - 20 kW; case 2: 100 % -
50 kW

10. OVERVIEW MODEL ANALYSIS CONCLUSIONSIMULATION
Analysis of a cogeneration system based on solid oxide fuel cell and air source heat pump with novel heat recovery
(Vialetto G., Noro M. and Rokni M.)
COP variation varying the external inlet air temperature
for four very different cases in terms of SOFC nominal
power and air relative humidity.

11. OVERVIEW MODEL ANALYSIS CONCLUSIONSIMULATION
Analysis of a cogeneration system based on solid oxide fuel cell and air source heat pump with novel heat recovery
(Vialetto G., Noro M. and Rokni M.)
Primary energy saving varying the external inlet air
temperature for four very different cases in terms of
SOFC nominal power and air relative humidity.

12. OVERVIEW MODEL ANALYSIS CONCLUSIONSIMULATION
Analysis of a cogeneration system based on solid oxide fuel cell and air source heat pump with novel heat recovery
(Vialetto G., Noro M. and Rokni M.)
A novel heat recovery for system composed by
ASHP and SOFC is proposed and analysed.
Simulations show that is possible to increase
efficiency of the system, COP is higher when a
powerful SOFC is available and when air has a
high relative humidity: in these cases SOFC
prevents freezing of evaporator section of ASHP.

13. THANK YOU FOR YOUR
ATTENTION
ANY QUESTION?
CONTACT
E-Mail: giulio@giuliovialetto.it
Site: www.giuliovialetto.it