An engineering example for unsustainable development

1. An engineering example for unsustainable development

2. How is electricity generated from non-renewable energy sources (oil, coal or natural gas)? Combined Power Plant (GT & ST) Diesel Generator Gas Turbine (GT) Steam Turbine (ST)

3. Electric Generator

4. Electrical output N Rotating wire loop Magnet S Electric Generator We need a rotating shaft? How to rotate the wire loop? http://electron9.phys.utk.edu/phys136d/modules/m8/images/gen.gif

5. Wind turbine gives a rotating shaft http://www.electricityforum.com/images/motor-eout.gif

6. Water turbine could also give a rotating shaft

7. Diesel generator It is a diesel engine coupled to a electric generator. Diesel engine provides the rotating shaft. http://www.rkm.com.au/animations/animation-diesel-engine.html

8. Diesel generator It is a diesel engine coupled to a electric generator. Diesel engine provides the rotating shaft. http://www.rkm.com.au/animations/animation-diesel-engine.html

9. Diesel generator http://www.myrctoys.com/engines/ottomotor_e.swf

10. Gas Turbine Power Plant fuel hot gases Combustion Chamber compressed air Comp- ressor Gas Turbine Gen fresh air gases to the stack

11. Gas turbine to produce electricity

12. Gas turbine driving a jet engine

13. Gas Turbine Power Plant

14. Gas Turbine Power Plant (QCC) in (WGT) out (WC) in fuel hot gases Combustion Chamber compressed air Comp- ressor Gas Turbine Gen fresh air gases to the stack

15. Gas Turbine Power Plant (QCC) in (WGT) out (WC) in fuel hot gases Combustion Chamber compressed air Comp- ressor Gas Turbine Gen fresh air gases to the stack Useful work output = ? Total heat input = ? Total energy loss = ?

16. Gas Turbine Power Plant (WGT) (WGT) (WC) (WC) in in out out (QCC) (QCC) in in Useful work output = - goes to electricity generation Total heat input = comes with the fuel Thermal efficiency of the GT power plant - ηthermal =

17. Gas Turbine Power Plant (WGT) (WGT) (WC) (WC) in in out out 72 – 78% of heat released by the fuel 22 – 28% Energy wasted: (QCC) (QCC) in in - ηthermal = = [ ] - = - = for 50 to 100 MW plant

18. Heat engine converts heat into work Hot reservoir at TH K Wout ηthermal = Qin Qin TC - Wout ηCarnot 1 = TH Qout ηCarnot ηthermal < Cold reservoir at TC K

19. Gas Turbine Power Plant (QCC) in Carnot efficiency of the GT power plant Lowest temperature (exhaust gas temperature) TC ηCarnot 1 - = TH Highest temperature (combustion chamber temperature) Maximum possible work output ηCarnot = Total heat input ηCarnot = Maximum possible work output

20. Gas Turbine Power Plant (QCC) (QCC) in in Second-law efficiency of GT power plant Useful work output = Maximum possible work output ηthermal = ηCarnot ηthermal = < 1 ηCarnot

21. Steam turbine http://www.bizaims.com/files/generator.JPG

22. Steam Turbine Power Plant Steam Turbine Gen

23. Steam Turbine Power Plant hot gases superheated steam compressed water Steam Generator Steam Turbine C Pump Gen Condenser saturated water saturated steam cooling water

24. Steam turbine to produce electricity Oil could be used instead of coal. R. Shanthini 15 Aug 2010 Steam engines are also used to power the train.

25. (QSG) in (WST) out WP in Steam Turbine Power Plant hot gases superheated steam compressed water Steam Generator Steam Turbine C Pump Gen Condenser saturated water saturated steam cooling water

26. (WST) (WST) out out 60 – 70% of heat released by the fuel Energy wasted: 30 – 40% (QSG) (QSG) in in Steam Turbine Power Plant - (WP) ηthermal in = = [ ] - - (WP) = in = for 200 to 800 MW plant

27. fuel GT gases to the stack atmospheric air hot gases ST C cooling water Combined Power Plant

28. fuel GT gases to the Stack ST atmospheric air hot gases ST C cooling water Combined Power Plant

29. Combined Power Plant

30. Combined Power Plant

31. 50 – 64% of heat released by the fuel Energy wasted: Combined Power Plant Useful work output at GT & ST ηthermal = Heat released by fuel 36 – 50% = = for 300 to 600 MW plant

32. ST cooling water Nuclear Power Plant Containment CORE Control rods PWR Pressurized water C

33. Nuclear power plant to produce electricity R. Shanthini 15 Aug 2010

34. 66 – 69% of heat released by the fuel Energy wasted: Nuclear Power Plant Useful work output at ST ηthermal = Heat released by fuel = 31 – 34% = for 500 to 1100 MW plant

35. According to the 2nd Law of Thermodynamics when heat is converted into work, part of the heat energy must be wasted

36. 50% - 70% lost in producing electricity 2% - 20% lost in transmitting electricity Generation, transmission and end-use losses

37. Typical energy losses in an industrialised country Electric power sector 70% energy losses Transportation sector 80% energy losses Residential & Commercial sector 25% energy losses Industrial sector 20% energy losses

38. A user of a car always asks for some minimum requirements while using a car. - The drive should be smooth and easy - The car should maintain a good speed so as to cope up with other cars in traffic - Easy and fast refuelling of cars - A good mileage - Less pollution

39. Eff Eff TC - 1 = TH Carnot Vehicles mostly uses Internal Combustion Engines TH = Flame temperature (800oC) TC = Exhaust Temperature (40oC) 313 K = - 1 1073 K Carnot ≈ 71%

40. A Typical Car: Urban Driving Engine losses in fuel energy conversion, In engine cooling and with exhaust gases 63 kJ Driveline losses 6 kJ Fuel Energy 18 kJ Aerodynamic drags 2.5 kJ 100 kJ 12 kJ Rolling resistance 4 kJ 17 kJ Standby Idle 5.5 kJ Braking Energy for accessories 2 kJ Source: http://www.fueleconomy.gov/feg/atv.shtml

41. A Typical Car: Highway Driving Engine losses in fuel energy conversion, In engine cooling and with exhaust gases 69 kJ Driveline losses 5 kJ Fuel Energy 25 kJ Aerodynamic drags 11 kJ 100 kJ 20 kJ Rolling resistance 7 kJ 4 kJ Standby Idle 2 kJ Braking Energy for accessories 2 kJ Source: http://www.fueleconomy.gov/feg/atv.shtml

42. Discussion Point 4: Is there a problem in burning oil and coal to make electricity and to drive automobiles in such an inefficient manner? Take 10 mins.

43. March of the Penguins Erin Brockovich The Big Ask The Story of Stuff and more…. Fossil fuel use Carbon dioxide Global warming Climate change Kyoto protocol should be watched under parental care etc.