Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
ME 562: Sustainable Energy – an Exergy Analysis Spring 2014
Absorption cooling
Absorption cooling 2/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
the Einstein-Szilard refrigerator
Absorption cooling 3/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
How it works – single effect
Absorption cooling 4/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
How it works – double effect
Absorption cooling 5/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
Process schematic
Cooling water from cooling tower / swimming pool
Cooling water from cooling tower / swimming pool
Chilled water serving cooling load
Hot water/glycol from solar or waste heat source
dilu
te L
iBr
solu
tion
conc
entr
ated
LiB
r so
luti
on
wat
er
hot water vapor
cold water vapor
Absorption cooling 6/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
Schematic – with temperatures
Cooling water from cooling tower / swimming pool
Cooling water from cooling tower / swimming pool
Chilled water serving cooling load
Hot water/glycol from solar or waste heat source
dilu
te L
iBr
solu
tion
conc
entr
ated
LiB
r so
luti
on
wat
er
hot water vapor
cold water vapor
27.0 oC
30.8 oC
10.0 oC16.0 oC
34.8 oC27.0 oC
100.0 oC100.0 oC91.5 oC
80.0 oC
7.0 oC
40.0 oC
7.0 oC
40.0 oC52.0 oC
80.0 oC67.6 oC
Absorption cooling 7/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
Thermodynamic states
?
Absorption cooling 8/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
Exergy flowsCooling water from cooling tower / swimming pool
Cooling water from cooling tower / swimming pool
Chilled water serving cooling load
Hot water/glycol from solar or waste heat source
dilu
te L
iBr
solu
tion
conc
entr
ated
LiB
r so
luti
on
wat
er
hot water vapor
cold water vapor
0.0209 kW0.1745 kW
0.7345 kW0.2608 kW
23.695 kW18.928 kW
0.4953 kW
- 0.8080 kW
0.113 kW
0.113 kW6.475 kW
10.652 kW
14.716 kW11.045 kW
0.0209 kW
0.4941 kW
Absorption cooling 9/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
Exergy destructionCooling water from cooling tower / swimming pool
Cooling water from cooling tower / swimming pool
Chilled water serving cooling load
Hot water/glycol from solar or waste heat source
dilu
te L
iBr
solu
tion
conc
entr
ated
LiB
r so
luti
on
wat
er
hot water vapor
cold water vapor
0.0209 kW0.1745 kW
0.7345 kW0.2608 kW
23.695 kW18.928 kW
0.4953 kW
- 0.8080 kW
0.113 kW
0.113 kW6.475 kW
10.652 kW
14.716 kW11.045 kW
0.0209 kW
0.4941 kW
Condenser0.2287 kW
Generator0.6617 kW
Evaporator0.4473 kW
Absorber2.895 kW
HX-0.507 kW
???
Absorption cooling 10/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
A comparable electric chiller
Absorption cooling 11/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
Performance vs. heat source T
Absorption cooling 12/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
Performance vs. CHW T
Absorption cooling 13/12
Mechanical EngineeringME462/562 Sustainable Energy:
an Exergy Analysis
Performance vs. HX