1. Lecture Objectives: Finish with Electric Energy Generation
Learn about Sorption Cooling

2. Power Generation Cycle

3. Gas powered turbine

4. Combustion product gas powered turbines
Limited to gas or oil as a major source of fuel
Approximately 55 to 65% of the power produced by the turbine is used for compressor.
Gas temperatures at the turbine inlet can be 1200ºC to 1400ºC
Because of the power required to drive the compressor, energy conversion efficiency for a simple cycle gas turbine plant is ~ 30%

5. Combined Cycle (gas and steam)

6. Combined heat and power (cogeneration CHP or three generation CCHP)
Here, we use
thermal energy
for heating and/or
cooling

7. Other method for CHP Here, we use mechanical energy for powering
vapor compression
cooling
systems

8. Absorption Cycle Same as vapor compression but NO COMPRESSOR
Replace compressor

9. Absorption cooling cycle
Relatively simple thermodynamics with adition of mixtures (water – aminia)
Rich solution of
Heat
H2O
H2O + NH3
Rich solution of
H2O
H2O + NH3

10. Mixtures (T-x diagram)
Dew point curve
Saturated vapor
Mixture of liquid and vapor
Saturated liquid
Bubble point curve
For P= 4 bar

11. h-x diagram hfg hfg Isotherms are ploted only in liquid region for H2O
for NH3
Isotherms are
ploted only
in liquid region

12. Composition of h-x diagram
Saturated vapor line at p1
Equilibrium construction line at p1 1e
Used to determine
isotherm line in
mixing region!
Start from x1;
move up to equilibrium
construction line;
move right to saturated
vapor line; determine 1’;
connect 1 and 1’.
Isotherm at P1 and T1
Adding energy B A x1
X1’
mass fraction of ammonia in saturated vapor

13. h-x diagram at the end of your textbook you will find these diagrams for 1) NH3-H2O 2) H2O-LiBr
LiBr is one of the
major liquid descants
in air-conditioning
systems

14. Adiabatic mixing in h-x diagram (Water – Ammonia)
From the textbook (Thermal Environmental Eng.; Kuehen et al)

15. Absorption cooling cycle
Rich solution of
Heat
H2O
H2O + NH3
Rich solution of
H2O
H2O + NH3

16. Mixing of two streams with heat rejection (Absorber)
mixture of
H2O and NH3 m2 m3
=pure NH3 (x2=1) m1 m3 m2 m1 2 Q
cooling
Heat rejection
Mixture of 1 and 2 3’
Mass and energy balance:
(1)
(2) 1 3
(3) x3 x
From mixture equation:
Substitute into (2)
Substitute into (3)
From adiabatic mixing
(from previous slide)