EE116x EXIT EXAM Power Plant Engineering

School of EECE 3rd Quarter, SY 2011-2012

General Instructions: The purpose of this exam is to test your full comprehension of the course stated above. Shade the circle of the letter corresponding to the correct answer in the answer sheet. Any form of cheating will nullify this examination. Pass this questionnaire together with the answer sheet to the proctor before the time ends. 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

Out of the following, which is not a nonconventional source of energy? A. Tidal Power B. Geothermal Energy C. Nuclear Energy D. Wind power Coal used in power plant is also known as A. Steam coal B. Charcoal C. Coke D. Soft coal The efficiency of thermal power plant improves with A. increased quantity of coal burnt B. larger quantity of water used C. lower load in the plant D. use of high steam pressures Power plants using coal work closely on known which of the following cycle? A. Otto cycle B. Binary vapor cycle C. Brayton cycle D. Rankine cycle Equipment used for pulverizing the coal is known as A. ball mill B. hopper C. burner D. stoker Which of the following is considered as superior quality of coal? A. Bituminous coal B. Peat C. Lignite D. Coke In a power plant, coal is carried from storage place to boilers generally by means of A. bucket B. V-belts C. trolleys D. manually The equipment installed in power plants to reduce air pollution due to smoke is A. induced draft fans B. de-super heaters C. electrostatic precipitators D. re-heaters Permissible pH value of water for boilers is A. 1 B. 7 C. slightly more than 7 D. 10 A condenser in a thermal power plant condenses steam combing out of A. boiler B. super-heater C. economizer D. turbine Overall thermal efficiency of a steam power station is in the range A. 18-24% B. 30-40% C. 44-62% D. 68-79% Which of the following is not the voltage at which power is usually transmitted? A. 132kV B. 66kV C. 33kV D. 20kV Most of the generators in thermal power plants run at A. 3000 rpm B. 1500 rpm C. 1000 rpm D. 750 rpm A load curve is a plot of A. Load versus generation capacity B. Load versus current C. Load versus time D. Load versus cost of power

15. For economy in generation power A. diversity factor should be high B. plant utilization factor C. load factor should be high D. load factor and diversity factor should be low 16. Which of the following category of consumers can provide highest load factor? A. A domestic consumer B. A continuous process plant C. A steel melting unit using arc furnace D. A cold storage plant 17. The normal connected load of a domestic consumer is usually A. up to 10 kW B. 10 to 20 kW C. 25 to 50 kW D. 50 to 100 kW 18. Load factor during a period is A. Average Load / Installed Capacity B. Average Load / Maximum Load C. Maximum Load / Average Load D. Maximum Load / Installed Capacity 19. Demand factor is the A. Maximum Demand / Average Demand B. Maximum Demand / Connected Load C. Average Demand / Maximum Demand D. Connected Load / Maximum Demand 20. In a system if the base load is the same as the maximum demand, the load factor will be A. 1 B. 0 C. infinity D. 1% 21. A system having connected load of 100 kW, peak load of 80 kW. base load of 20 kW and average load of 40 kW, will have a load factor of A. 40% B. 50% C. 60% D. 80% 22. Which plant can never have 100% load factor? A. Nuclear power plant B. Hydro electric plant C. Peak load plant D. Base load plant 23. The ratio, maximum demand of the installation / sum of individual maximum demands is known as A. Demand factor B. Plant use factor C. Diversity factor D. Plant capacity factor 24. A power plant supplying energy to a city will usually experience peak demand A. from midnight to early morning B. 8 AM to 12 noon C. 2 PM to 6 PM D. 6 PM to 12 PM 25. In a power plant a reserve generating capacity which is in operation but not in service is known as A. Hot reserve B. Cold reserve C. Spinning reserve D. Firm power 26. In an interconnected system consisting of a nuclear power stations, steam station and diesel generating station, which plant can be used as base load plant ? A. Steam station B. Diesel generation plant C. Nuclear power station D. Any of the above 27. Capital cost per MWh is highest in case of A. steam power plants B. diesel engine power plants C. nuclear power plants D. hydroelectric power plants

28.

29.

30.

31.

32.

33.

34.

35.

36.

37.

For questions 28 to 31: The annual peak load on a 30 MW power station is 25 MW. The power station supplies loads having maximum demands of 10 MW, 8.5 MW, 5 MW and 4.5 MW. The annual load factor is 45%. The average load is A. 1025 kW B. 1125 kW C. 1425 kW D. 1625 kW Total energy supplied in a year is A. 9,875,000 kWh B. 8345,000 kWh C. 7450,000 kWh D. 6395,000 kWh Diversity factor is A. 3.80 B. 1.02 C. 1.12 D. 1.22 Demand factor is A. 0.75 B. 0.83 C. 0.89 D. 0.45 In a steam power plant which component needs maximum maintenance attention? A. Condenser B. Boiler C. Turbine D. Water treatment plant As the load factor approaches unity, the shape of load duration curve will be nearly A. L shaped B. inverted T shaped C. triangular D. rectangular When maximum and average loads are equal, the load factor will be A. 0 B. 0.01 C. 0.5 D. 1 Which of the following relation is incorrect? A. Capacity factor = Utilization factor x Load factor B. Load factor x Maximum load = Average load C. Demand factor x Connected load = Maximum demand D. None of the above Capacity factor and load factor become identical when A. peak load is equal to the capacity of the plant B. Average load is half the capacity of the plant C. Average load is same as peak load D. Group diversity factor is equal to peak diversity factor A low utilization factor for a plant indicates that A. plant is under maintenance B. plant is used for base load only C. plant is used for stand by purpose only D. plant is used for peak load as well as base load

For questions 38 to 40: Power plants considered are I. Diesel II. Thermal III. Hydro IV. Nuclear 38. Plants in ascending order of capital cost per MW are A. I, II, III, IV B. II, III, IV, I C. III, IV, I, II D. IV. Ill, I, II 39. Plants in descending order of their expected useful life are A. I, III, II, IV B. II, I, III, IV C. III, II, IV, I D. IV, I, II, III 40. Plants in ascending order of their operating cost per MWH generated are A. IV, I, II, III B. III, II, IV, I C. II, I, III, IV D. I, III, II, IV 41. When a power plant is not able to meet the demand of consumers it will resort to A. penalizing high load consumers by increasing the charges for electricity B. power factor improvement at the generators C. efficient plant operation D. load shedding

42. Which of the following power plants can generate power at unpredictable or uncontrollable times? A. Wind power plant B. Tidal power plant C. Solar power plant D. Any of the above 43. Maximum demand tariff is generally not applied to domestic consumers because A. they cannot afford today B. they consume less power C. their load factor is low D. their maximum demand is low 44. HRC fuses provide best protection against A. short circuits B. lightning C. sparking D. fire 45. Sparking occurs when a load is switched off because the circuit has high A. inductance B. resistance C. capacitance D. magnetism 46. Zero sequence component always flows through A. phase wires B. neutral wire C. earth wire D. any of the above 47. Base load plants have A. high capital cost, high operating cost and high load factor B. high capital cost, low operating cost and high load factor C. low capital cost, low operating cost and low load factor D. low capital cost, high operation cost and high load factor 48. Which alternator will have more number of poles A. coupled to hydraulic turbine B. coupled to steam turbine C. coupled to gas turbine D. all will have same number of poles 49. Which alternator usually runs at slow speed as compared to others A. coupled to gas turbine B. coupled to steam turbine C. coupled to hydraulic turbine D. coupled to diesel engine 50. Which type of plant has the least running cost per kWh of energy generated? A. Hydro-electric plant B. Thermal power plant C. Nuclear power plant D. Diesel power plant

* * * * END OF EXAM * * * *

KEY TO CORRECTION

1. C 3. D 5. A 7. B 9. C 11. A 13. A 15. B 17. A 19. B 21. B 23. C 25. A 27. C 29. A 31. B 33. D 35. D 37. C 39. C 41. D 43. D 45. A 47. B 49. C

2. A 4. D 6. A 8. C 10. D 12. D 14. C 16. B 18. B 20. A 22. C 24. D 26. C 28. B 30. C 32. 34. D 36. A 38. A 40. B 42. D 44. A 46. B 48. A 50. A