1. Lecture Objectives: Answer question related to Project 1 assignment
Discus the Final Project
Learn about Electric Energy Generation

2. Project 1
New example matlab code on the course website

3. Final Project Expand this Project Variable speed pumps
Different type of chillers
Different buildings ….
Modeling of processes in the psychrometric chart
Will discuss with you in one on one meeting
Your ideas from your research, work, internship, life,…
Meetings: Today from 2 to 3 pm
Tuesday all morning and from 2 pm to 3 pm

4. Power generation

5. Power generation in steam turbines (Rankine cycle)
Pump
Nuclear
Coal

6. Steam powered turbine

7. Ideal Rankine Cycle
1-2 isentropic pump constant pressure heat addition
3-4 isentropic turbine constant pressure heat rejection

8. Ideal Rankine Cycle h1=hf saturated liquid
Wpump (ideal)=h2-h1=vf(Phigh-Plow)
vf=specific volume of saturated liquid at low pressure
qin=h3-h heat added in boiler
Usually either qin will be specified or else the high temperature and pressure (so you can find h3)
qout=h4-h1 heat removed from condenser)
wturbine=h3-h4 turbine work

9. Deviations from Ideal in Real Cycles
Pump is not ideal
Turbine is not ideal
There is a pressure drop across the boiler and condenser
We need to sub-cool the liquid in the condenser to prevent cavitation in the pump.

10. For increasing system efficiency of Rankine Cycle
Lower condenser pressure
We should have at least 10°C DT between condenser and cooling water or air temperature for effective heat transfer
The quality at exit to prevent turbine problems shouldn’t go less than about 88%
Superheat the steam more
Tmax ~ 620° due to material stress
Increase boiler pressure (with same Tmax)
Pmax ~ 30 MPa
This affects the quality at exit!

11. Reheat Cycle
It allows increase boiler pressure without problems of low quality at turbine exit

12. Regeneration
Preheats steam entering boiler using a feed-water heater, improving efficiency

13. Further improvements

14. Analogy with cooling cycles

15. Gas powered turbine

16. 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%

17. Combined Cycle (gas and steam)

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

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