The inductive reactance of the line is 0.25 cis
(35 deg) ohm per km. What is the total
reactance of the line at 20 km? Select one: a.
0.0125cis 25 deg b. 0.125cis 35 deg c. 5cis 35
deg d. 0.25cis deg
A diesel power station has a fuel consumption of
0.37 lb/kWh, the calorific value of fuel being
30,000 BTU/lb. Determine the engine efficiency
if the generator efficiency is 95% neglect brake
power on the engine. Select one: a. 29% b. 34%
c. 36% d. 32%
A hydro-electric plant generates 100 MW at an
available head of 200 m and at an overall
efficiency of 75% what quantity of water in in
cubic meter per second is required? Select one:
a. 1200 b. 68 c. 26 d. 122
An industrial plant has a peak load of 80 MW,
daily load factor of 60%, daily capacity factor
80% and plant factor is 75%. Calculate the daily
energy consumption.
Select one:
a. 1198 MWhr
b. 1350 MWhr
c. 1208 MWhr
which cost P800/kVA with annual interest and
depreciation of 10%. The demand charge is
P500/kVA maximum demand. What is the
annual savings after putting capacitor? Select
one: a. P 13,467.00 b. P 41,667.00 c. P
38,983.00 d. P 12,755.00
A 100 MW power plant burns 0.4 kg coal with a
heating value of 7.2 x 10^6 cal/kg to produce
one KWh. The plant is a base load plant and
runs 24 hrs at full load. How many tons of coal is
needed per day? Select one: a. 830 b. 960 c.
250 d. 625
Daytime capacity when only 300 MW pump
storage plant and 600 MW nuclear plant is
operating ____. Select one: a. 600 MW b. 500
MW c. 900 MW d. 300 MW
A power plant gets water from a dam from a
height of 122.35 meters at the rate of 1000 cubic
meters per minute. If the output of the plant is
15,000 kW, what is the plant efficiency? Select
one: a. 65% b. 70% c. 80% d. 75%
Suppose that the consumption of energy in a
certain country has a growth rate of 4% per
year, in how many years will the energy
consumption be tripled? Select one: a. 17.33 yrs
b. 24.47 yrs c. 34.66 yrs d. 27.47 yrs
d. 1080 MWhr
diversity factor of 4.2 gives a savings of ______
percent in the generating equipment Select one:
a. 76 b. 40 c. 80 d. 26
A hydroelectric plant generates 100 MW at an
available head 200 m, and at an overall
efficiency of 75%. What quantity of water in
cubic meter per second is required? Select one:
a. 68 b. 26 c. 122 d. 1220
A water pump discharges 100 gpm for a depth
of 900 ft, friction loss is 4.4%. The motor has a
efficiency of 70%. If the cost of energy is P4.00
per kWh, what is the total cost of electric energy
to have one cubic meter of water? Select one: a.
P4.46 b. P12.25 c. P70.45 d. P1.12
An industrial plant has the maximum demand of
750 kVA at 80% p.f. lagging. It is desired to
improve the p.f. to 95% using shunt capacitors
A hydro-electric plant generates 100 MW at an
available head of 200 m and at an overall
efficiency of 75% what quantity of water in in
cubic meter per second is required? Select one:
a. 26 b. 1200 c. 122 d. 68
An industrial plant has a maximum demand of
400 kVA at 78% p.f. lagging consumes 100,000
kWh per month. Calculate the monthly bill of this
plant. Given the following rates: Demand
Charge: P220.00/kVA maximum demand per
month; Energy Charge: P2.22/kWh per month;
Power factor adjustment rate: 0.6% surcharge
for every percentage point lower than 85% p.f.
and 0.3% discount for every percentage point
higher than 85% p.f. Select one: a. P 222,000.00
b. P 88,000.00 c. P 277,561.00 d. P 323,020.00
The maximum tidal head available for proposed
tidal-power station is 7 m. What must be the
area of the tidal bay to generate an average of
1,200 MW of power? Select one: a. 121 sq km
b. 126 sq km c. 102 sq km d. 112 sq km
Estimate the average power output of a wind
turbine having a blade diameter of 35 ft if the
wind velocity ranges from 10 to 30 mph? Select
one: a. 3.014 kW b. 24.11 kW c. 81.364 kW d.
42.40 kW
The current loads of four circuits are as follows:
Circuit No. 1 = 25, Circuit No. 2 = 38 amp,
Circuit No. 3 = 18 amp, Circuit No. 4 = 45 amp.
If the diversity factor is 1.5, what is the minimum
ampacity of the feeder conductor? Select one: a.
189 Amp b. 84 Amp c. 126 Amp d. 152 Amp
One million cu meter of water is stored in a
reservoir feeding water turbine. If the center of
mass of the water is 50 m above the turbine and
losses are negligible, how much energy (in
MWh) will that volume of water produce? The
density of water is 993 kg/m^3. Select one: a.
136.3 b. 153.5 c. 135.3 d. 163.6
The net energy required of a certain country in
year 2000 was approximately 3 x 10^6 GWh.
What is the equivalent value in quad? Select
one: a. 12.24 b. 102.4 c. 10.24 d. 124.2
A hydroelectric plant generates 100 MW at an
available head 200 m, and at an overall
efficiency of 75%. What quantity of water in
cubic meter per second is required? Select one:
a. 68 b. 122 c. 26 d. 1220
A device which monitor and operates when
certain level has been reached Select one: a.
relay b. transformer c. monitor d. oscilloscope
If the voltage of a distribution cable is increased
to n times, the weight of the copper required for
the new distributor of will be Select one: a.
increased to n times b. reduced to 1/n^2 times
c. increased to n^2 times d. reduced to n times
EE 116
FINAL EXAM
NAME______________________________________
INSTRUCTION : Select the correct answer for each of the following questions. Mark
only
one answer for each item by shading the box corresponding to the letter of your choice
on the answer sheet provided by the school. STRICTLY NO ERASURES ALLOWED.
1. Which of the following is a non-renewable source of energy?
A. solar
C. nuclear
B. wind
D. hydro
2. What is the reason why thermal power plant decrease capacity during summer?
A. decrease water level at the lake
C. taking a bath or swimming on lake
B. temperature rise of the lake
D. there is no rain
3. An effective remover of dusts, carbon particles and others from the flue gas of power
plant?
A. Electrostatic precipitator
C. Mechanical collector
B. Soot blower & collector
D. Dust scrubber
4. The efficiency of the thermal power plant improves with _____.
A. increased quality of coal burnt
C. lower load in the plant
B. use of high steam pressure
D. larger quantity of water used
5. Which of the following is the least efficient power plant?
A. Diesel
C. Coal fired
B. Gasoline
D. Combined cycle
6. Which of the following power plant will take least time in starting from cold condition to
full load condition?
A. Nuclear power
C. Gas turbine
B. Steam turbine
D. Hydro-electric
7. Geothermal power plant is most suitable for ______.
A. Stand-by plant
C. Regulating plant
B. Peak load plant
D. Base load plant
8. Which power plant can have a single unit up to 100 MW?
A. Hydro electric power plant
C. Steam power plant
B. Diesel power plant
D. Nuclear power plant
9. In fission, energy is produced when ______.
A. chemical compound splits into its constituents C. nuclear particle combine
B. nuclear particles split
D. molecules combine
10. Which of the following energy generators is NOT an atmosphere pollutant?
A. Light crude power plant
C. Solar power plant
B. Gas-fired plant w/ electrostatic dust collector D. Biogas plant
11. The net energy required of a certain country in yr 2000 was approximately 3 x10 6 GWh.
What is the equivalent value in quad?
A. 12.42
C. 124.2
B. 10.24
D. 102.4
12. In a power station, 4 x104 GWh of energy is to be produced in 1 yr, half from coal and
half from natural gas. The energy content of coal is 900 W-yr per ton, and that of natural
gas is 0.03 W-yr per ft3. How much coal will be required?
A. 5.07x106 tons
C. 2.53 x106 tons
6
B. 7.05 x10 tons
D. 5.23 x106 tons
13. Natural gas reserve in a certain country is estimated at 100 x109 ft3, with an energy
content of 0.025 W-yr per ft3, if the present peak power demand is 0.5 GW and the
power demand growth rate is 5% and all the energy is to be supplied by natural gas,
approximately how long will the reserve last?
A. 4.64 yrs
C. 4.46 yrs
B. 6.44 yrs
D. 6.64 yrs
14. A 100 MW power plant has a heat rate of 2.88x106 Calories per kWh. it is a base load
plant and runs at full load 24 hrs a day. How many tons of coal is needed per day?
Heating value of coal is 13,000 btu per lb.
A. 250
C. 830
B. 625
D. 960
15. A thermal power plant consumes 3600 tons of coal per day. If coal has an average
energy content of 10,000 BTU/lb, what is the plant’s power output? Assume an overall
efficiency of 24%.
A. 211 MW
C. 112 MW
B. 879 MW
D. 789 MW
16. Hydroelectric power is generated at a dam that produces a head of 180 ft and a
reservoir containing 3 x106 gallons of water. How much energy can be generated from
this reservoir by a turbine-generator system whose overall efficiency is 20%?
A. 7761.5 MJ
C. 6126.5 MJ
B. 1552.3 MJ
D. 1225.3 MJ
17. A hydroelectric plant generates 100 MW at an available head of 200 m, and at an
overall efficiency of 75%, what quantity of water in cubic meter per second is required?
A. 68
C. 1220
B. 122
D. 26
18. A wind generator with an efficiency of 80% has a blade diameter of 20 m. If the wind
velocity is 35 kph, how much power is obtainable from the generator?
A. 4.32 kW
C. 5.47 kW
B. 54.7 kW
D. 43.2 kW
19. The maximum tidal head available for a proposed tidal-power station is 7m. What must
be the area of the tidal bay to generate an average of 1,200 MWatts of power?
A. 112 sq km.
C. 126 sq km.
B. 102 sq. km
D. 121 sq. km.
20. A power customer is applying for source listed the loads as follows:
5–15 hp motors, 3–5 hp motors, lighting loads 8 kW, miscellaneous loads 3.5 kW
The demand factor is 65% and the power factor is 80% wherein the load factor is 46%.
What is the maximum kW demand for the customer?
A. 78
C. 51
B. 64
D. 69
21. If a generating station has an annual load factor of 30.5 % and the maximum load on
the substations were 7,500 kW, 5,000 kW, 3,400 kW, 4,600 kW and 2,800 kW. Diversity
factor among substations is 1.3. What is energy generated annually for the station?
A. 48,878 MWh
C. 47,887 MWh
B. 65,532 MWh
D. 62,253 MWh
22. A power plant has a maximum demand of 15 MW. The annual load factor and capacity
factor are 50 % and 40 % respectively. Determine the reserve capacity of the plant.
A. 7530 kW
C. 5730 kW
B. 3750 kW
D. 3075 kW
23. A power plant is said to have a use factor of 48.5% and a capacity factor of 42.4%. How
many hours did it operate during the year?
A. 7,568 hrs
C. 7,658 hrs
B. 1,102 hrs
D. 8,000 hrs
24. A generating station has a maximum demand of 40 MW, annual load factor of 75%,
annual plant capacity factor of 65% and a plant use factor of 85%. What is the annual
energy produced?
A. 200.9 x106 kWh
C. 148.9 x106 kWh
6
B. 195.6 x10 kWh
D. 812.3 x106 kWh
25. Which of the following generating station has the minimum running cost?
A. Nuclear power
C. Diesel plant
B. Thermal plant
D. Hydro-electric plant
26. Depreciation charges are high in the case of what power plant?
A. Windmill plant
C. Diesel plant
B. Hydro-electric plant
D. Thermal plant
27. An industrial plant has a maximum demand of 750 kVA at 80% p.f. lagging. It is desired
to improve the p.f. to 95% using shunt capacitors which cost P800/kVA with annual
interest and depreciation of 10%. The demand charge is P500/kVA maximum demand.
What is the annual savings after putting capacitor?
A. P41,667.00
C. P13,467.00
B. P12,755.00
D. P38,983.00
28. Suppose that the consumption of energy in a certain country has a growth rate of 4%
per year. In how many years will the energy consumption be tripled?
A. 24.47 yrs
C. 27.47 yrs
B. 17.33 yrs
D. 34.66 yrs
29. In a certain country the equivalent fuel reserve for power generation is 3 x106 MW-yrs.
The present peak power demand is 200 GW, and the expected power consumption
growth rate is 2.1%. How long will the fuel reserve last?
A. 13 yrs
C. 11 yrs
B. 14 yrs
D. 12 yrs
30. A power plant consumes 100,000 lbs of coal per hour. The heating value of the coal is
12,000 BTU per pound. The overall plant efficiency is 30%. What is the kW output of the
plant?
A. 175,000 kW
C. 142,500 kW
B. 205,000 kW
D. 105,500 kW
31. A 100 MW power plant burns 0.4 kg coal with a heating value of 7.2 x106 cal/kg to
produce one kWh. The plant is a base load plant and runs 24 hrs at full load. How many
tons of coal are needed per day?
A. 830
B. 960
C. 250
D. 625
32. A diesel power station has a fuel consumption of 0.37 lb/kWh, the calorific value of fuel
being 30,000 BTU/lb. Determine the engine efficiency if the generator efficiency is 95%
neglect brake power on the engine.
A. 29%
C. 36%
B. 32%
D. 34%
33. Estimate the average power output of a wind turbine having a blade diameter of 35 ft if
the wind velocity ranges from 10 to 30 mph?
A. 3.014 kW
C. 24.11 kW
B. 81.364 kW
D. 42.20 kW
34. A ten-year investigation of a river’s potential gave an average water flow of 25 cm per
second at the bottom and 90 cm per second at the surface. The average cross-section
at the same location is 80 m2. What is the average flow rate in cubic meter per hour?
A. 5,760
C. 165,000
B. 57,500
D. 46,500
35. A power plant gets water from a dam from a height of 122.45 meters at the rate of 1,000
cubic meters per minute. If the output of the plant is 15,000 kW, what is the efficiency?
A. 75 %
C. 80 %
B. 70 %
D. 65 %
36. One million cu meter of water is stored in a reservoir feeding water turbine. If the center
of mass of the water is 50 m above the turbine and losses are negligible, how much
energy (in MWh) will that volume of water produced? The density of water is 993 kg/m 3.
A. 135.3
C. 136.3
B. 153.5
D. 163.6
37. A diversity factor of 4.2 gives a savings of ____ percent in the generating equipment.
A. 80
C. 26
B. 40
D. 76
38. The current loads of four circuits are as follows :
Circuit No. 1 = 25 Amp
Circuit No. 3 = 18 Amp
Circuit No. 2 = 38 Amp
Circuit No. 4 = 45 Amp
If the diversity factor is 1.5. What is the minimum ampacity of the feeder conductor?
A. 126 Amp
C. 84 Amp
B. 189 Amp
D. 152 Amp
39. The power customer has four circuits of 220 Volts, three-phase. The circuits have the
maximum demand as follows: Circuit-1 = 35 Amp, Circuit-2 = 46 Amp, Circuit-3 = 72
Amp, & Circuit-4 = 57 Amp. The diversity factor is 1.5, the load factor is 50%, and the
power factor is 80%. What is the approximate kW demand of the customer?
A. 15 kW
C. 43 kW
B. 21 kW
D. 53 kW
40. The power customer has four circuits of 220 Volts, three-phase. The circuits have the
maximum demand as follows:
Circuit No. 1 = 35 Amp;
Circuit No. 3 = 72 Amp;
Circuit No. 2 = 46 Amp;
Circuit No. 4 = 57Amp
The diversity factor is 1.5, the load factor is 50%, Determine the maximum kVA demand
on the customer?
A. 46 kVA
C. 80 kVA
B. 26.5 kVA
D. 53 kVA
41. Daytime capacity when only 300 MW pump storage plant and 600 MW Nuclear Plant is
operating ____.
A. 500 MW
C. 600 MW
B. 900 MW
D. 300 MW
42. The metering of a power customer was read and gave the following data :
kW-hr = 200,000, Maximum demand = 380 kW, kVAR-hr = 180,000, billing days = 30
What is the load factor?
A. 68 %
C. 73 %
B. 80 %
D. 62 %
43. A generating plant rated 100 MW 90% power factor has a load factor of 65% for a
certain day. The minimum output was 40 MW. How many kWh generated for that day?
A. 2,160,000 kWh
C. 1,560,000 kWh
B. 960,000 kWh
D. 2,400,000 kWh
44. The annual peak load on a 15 MW power plant is 10.5 MW. Two substations are
supplied by this plant. Annual energy dispatched through substation A is 27,500 MWh,
while 16,500 MWh are sent to substation B. Neglecting line losses. What is the annual
capacity factor of the plant?
A. 35.3%
C. 33.5%
B. 47.8%
D. 30.5%
45. An industrial plant has a peak load of 80 MW, daily load factor of 60%, daily capacity
factor of 75% and plant use factor of 80%. Calculate the daily energy consumption.
A. 1198 MWhr
C. 1080 MWhr
B. 1208 MWhr
D. 1350 MWhr
46. A power plant has an annual factors as follows: Load 58.5 %, Capacity 40.9 % and
Use 45.2 %. The reserve carried over and above peak load is 8900 kW. The hours per
year not in service and installed capacity of this plant are respectively.
A. 792 hrs & 20,346 kW
C. 833 hrs & 39,147 kW
B. 933 hrs & 49,417 kW
D. 822 hrs & 30,463 Kw
47. The annual load duration curve of a certain power station can be considered as a
straight line from 20 MW to 4 MW. To meet this load, 3 turbo-alternator units, two rated
at 10 MW each and one rated 5 MW are installed. Determine the plant use factor.
A. 80 %
C. 48 %
B. 60 %
D. 38 %
48. A generating station has the following data : Installed capacity = 300 MW, Annual load
factor = 60%, Annual Capacity factor = 50%, Annual interest & depreciation = 10 %
Annual cost of fuel, oil etc. = P90 Million, Capital Cost = P1,000 Million. What is the cost
per kWh generated?
A. P0.24
C. P0.20
B. P0.14
D. P0.10
49. A diesel plant has an overall efficiency of 30% the heating value of diesel is 18,000
BTU/lb. if diesel cost P6.00 per liter. What is the fuel cost of production in peso per
kWh. Take density of diesel to be 900 grams per liter.
A. P1.85/kWh
C. P2.12/kWh
B. P1.91/kWh
D. P2.45/kWh
50. A diesel generator set burns diesel with a heating value of 18,000 BTU per lb. The
diesel engine has an efficiency of 30% and the alternator has an efficiency of 95%.
Determine the fuel cost component of producing one KWh if diesel costs P2.80 per lbs.
A. P0.15
C. P2.15
B. P1.86
D. P3.28
EE 116
FINAL EXAM
NAME______________________________________
INSTRUCTION : Select the correct answer for each of the following questions. Mark only
one answer for each item by shading the box corresponding to the letter of your choice on the answer sheet provided by
the school. STRICTLY NO ERASURES ALLOWED.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
Which of the following hydraulic drive is suitable for low head
A Propeller wheel
C. Flywheel
B. Impulse wheel
D. Reaction wheel
Plants capable of carrying load for time interval during off-peak or peak periods and usually responds to changes in
system frequency .
A Base load Plant
C. Standby Plant
B. Peaking Plant
D. Regulating Plant
Which of the following is the least efficient power plant.
A Diesel
C. coal fired.
B. Gasoline
D. combined cycle
Which of the following generating station has the least running cost?
A. Thermal Power Station
C. Nuclear Power Station
B. Hydro Power Station
D. Diesel Power station
Which of the following generating station has the highest initial cost?
A. Thermal Power Station
C. Nuclear Power Station
B. Hydro Power Station
D. Diesel Power station
It is a power plant where energy is generated during periods of high system demand using water which has been
pumped into a reservoir usually during periods of low system demand.
A. Reservoir Power Plant
C. Nuclear Power Station
B. Pumped storage plant
D. Run-of-river plant
Refers to the units available, maintained at operating temperature & ready for service although not in actual
operation.
A. Cold Reserve Plant
C. Spinning Reserve Plant
B. Hot Reserve Plant
D. Generator
Plant that is normally assumed load requirements under normal condition.
A. Base load Plant
C. Regulating Plant
B. Peaking Plant
D. Reserve power Plant
It is an open or closed conduits made of reinforced concrete or steel which carry water to the turbine.
A. Spillway
C. Surge Tank
B. Penstock
D. Dam
It is a part of steam generating plant that increases the temperature of water before it enters into the boiler
A. Superheater
C. boiler
B. Economizer
D. air preheater
It is a part of steam generating plant that converts water into steam
A. Superheater
C. boiler
B. Economizer
D. air preheater
Steam power station works of what power cycles?
A. Rankine
C. Otto
B. Brayton
D. Erickson
The plant is also used as standby sets for continuity of supply such as in hospitals, radio stations, cinema and
telephone exchanges.
A Diesel
C. coal fired.
B. Geothermal
D. Hydro-electric
Which of the following relation is INCORRECT ?
A. capacity factor = utilization factor x load factor C. load factor x maximum load = ave. load
B. demand factor x connected load = maximum demand
D. none of these
The area under daily load curve divided by 24 hours gives ……
A. Peak demand
C. least load
B. average load
D. total kwh generated
The area under daily load curve gives what?
A. peak demand
C. least load
B. average load
D. total kwh generated
The ratio of maximum demand of the system and the connected load of the system is known as
A. capacity factor
C. load factor
B. demand factor
D. plant use factor
The ratio of average load of the system and the maximum demand of the system is known as
A. capacity factor
C. load factor
B. demand factor
D. plant use factor
The ratio of total energy Produced by the plant and the product of maximum demand & service hour is known as
A. capacity factor
C. load factor
B. demand factor
D. plant use factor
The ratio of total energy Produced by the plant and the product of Generator capacity & service hour is known as
A. capacity factor
C. load factor
B. demand factor
D. plant use factor
21. Knowledge of diversity factor helps in determining
A. Plant capacity
C. average load
B. peak load
D. kwh generated
22. The ratio of sum of individual maximum demand and simultaneous maximum demand of the system is known as
A. Diversity factor
C. load factor
B. demand factor
D. plant capacity factor
23. What is the reciprocal of diversity factor?
A. Coincidence factor
C. utilization factor
B. power factor
D. inverse factor
24. The ratio of energy output of the plant and the maximum energy that could have been produced is known as
A. capacity factor
C. load factor
B. demand factor
D. plant use factor
25. The ratio of maximum demand of the system and the installed capacity of the system is known as
A. capacity factor
C. utilization factor
B. demand factor
D. plant use factor
26. This refers to the sum of continuous rating of the equipment connected to the supply system.
A. maximum demand
C. average load
B. average kWh
D. connected load
27. Which of the following terms that plays key role determination of cost per kwh?
A. Diversity factor
C. load factor
B. demand factor
D. plant capacity factor
28. What will happen when the load factor is increase?
A. cost per kwh will increase
C. cost per kwh will double
B. cost per kwh will decrease
D. cost per kwh will remain the same
29. The running cost at the generating station is an account of ______
A. annual cost of fuel
C. annual repair and maintenance
B. annual salaries of operating staff
D. all of the above
30. While calculating the cost of electric power, which of the following is not considered a fixed cost?
A. interest on capital investment
C. most of salaries and wages
B. taxes and insurance
D. repair and maintenance
31. In a certain country the equivalent fuel reserve for power generation is 3 x 10 6 MW. yrs. The present peak power
demand is 200GW, and the expected power consumption growth rate is 2.1%. How long will the fuel reserve last?
A. 16 years
C. 25 years
B. 13 years
D. 12 years
32. In a certain region the growth rate of energy consumption is 6%. In how many years will the energy consumption
be quadrupled?
A. 23.1
C. 26.8
B. 22.5
D. 32.5
33. What is the average output of a wind turbine in kw having a blade diameter of 35 ft if the wind velocity ranges
from 10 to 30 mi/hr.
A. 2.42
C. 24.2
B. 42.2
D. 224
34. The maximum tidal head available for the proposed tidal power station is 6 m. What must be the area in km 2 of the
tidal bay to generate an average of 1000 MW of power?
A. 126.8
C. 128.6
B. 168.2
D. 186.2
35. A diesel plant has an overall efficiency of 30% the heating value of diesel is 18,000 BTU per lb. If diesel cost P6.00
per liter. What is the fuel cost of production in peso per kWh. Take density of diesel to be 900 grams per liter.
A. P10.57
C. P12.25
B. P13.85
D. P11.45
36. The annual load factor of a 50 MW of the plant is 65%. Calculate the annual energy delivered by the plant if the
utilization factor is 70%.
A. 227,760 MWHRS
C. 199,290 MWHRS
B. 722,760 MWHRS
D. 627,720 MWHRS
37. The metering of a power customer was read and gave 200,000 kw-hr for 30 days register a maximum demand of
350 kW.
What is the load factor ?
A. 68 %
C. 73 %
B. 79 %
D. 62 %
38. A certain power station supplies 3 circuits, Residential with 10 kw maximum demand, Commercial with 25 KW
maximum demand and Industrial of 15 kw maximum demand. Calculate the total kw maximum demand at the
station if the station diversity factor is 1.5.
A. 25
C. 33
B. 20
D. 50
39. A power plant is said to have a use factor of 48.5% and a capacity factor of 45.4%. How many hours did it operate
during the year?
A. 7,568 hrs
C. 7,658 hrs
B. 1,102 hrs
D. 8,200 hrs
40. A customer connected to a substation have a connected load of 43,000 kW at a demand factor of 58%. The total
units consumed annually is 83x106 kWh. What is the annual load factor of the station ?
A. 53%
C. 22%
B. 56%
D. 38%
41. The power customer has four circuits of 220 Volts, three-phase. The circuits have the maximum demand as
follows:
Circuit No. 1 = 35 Amp;
Circuit No. 3 = 72 Amp;
Circuit No. 2 = 46 Amp;
Circuit No. 4 = 57Amp
The diversity factor is 1.5, the load factor is 50% and power factor of 0.8, Determine the KWHR consumption of
the customer?
A. 468,667
C. 567980
B. 186,558
D. 535,656
42. The annual maximum demand of a 55 MW generating plant is 50 MW and produces an annual energy of 265,000
MWh. What is the annual load factor of the plant ?
A. 55%
C. 80%
B. 75%
D. 60.5%
43. A power plant has a maximum demand of 15 MW. The annual load factor and capacity factor are 50 % and 40 %
respectively. Determine the reserve capacity of the plant.
A. 7530 kW
C. 5730 kW
B. 3750 kW
D. 3075 kW
44. The annual load duration curve of a certain power station can be considered as a straight line from 20 MW to 4
MW. To meet this load, 3 turbo-alternator units, two rated at 10 MW each and one rated 5 MW are installed.
Determine the plant capacity factor.
A. 48%
C. 80%
B. 60%
D. 38%
45. A power plant is said to have a use factor of 48.5% and a capacity factor of 42.4%. How many hours did it rest
during the year?
A.7,568 hrs
C. 7,658 hrs
B.1,102 hrs
D. 1101 hrs
46. A generating station has the following data :
Installed capacity
= 300 MW
Annual load factor
= 60 %
Capacity factor
= 50 %
Annual interest & depreciation = 10 %
Annual cost of fuel, oil etc. = P90 Million
Capital Cost
= P1,000 Million
The cost per kWh generated is ……...
A. P0.24
C. P0.14
B. P0.20
D. P0.10
47. Determine the load factor at which the cost of supplying a unit of electricity from a diesel and from a steam station
is the same. The annual fixed and running charges for diesel are P 300.00 per kW and P 0.25 per kWh respectively,
while for steam are P 1,200 per kW and P 0.0625 per kW-hr respectively.
A. 50 %
C. 58 %
B. 55 %
D. 60 %
48. The following two tariff are offered:
a. P (125 + 0.15/kWH)
b. At flat rate P 0.4/kWH
At what consumption in kWh is the first tariff Economical ?
A. 500 KWH
C. 250 KWH
B. 125 KWH
D. 300 KWH
49. Calculate the annual bill of a consumer whose MD is 500 kW, pf = 0.8 lagging and LF = 70% . The tariff used is P
100/KVA of MD plus P 0.25/ kW-hr consumed?
A. P 890,114
C. P 765,148
B. P 829,000
D. P 940,300
50. A consumer requires 0ne million kWh per year and his annual load factor is 50%. The tariff enforce is P120 per kW
maximum demand plus P0.05 per kWh consumed. Estimate the savings in energy charges if he improve his load
factor is raised to 100%.
A. P 77,397.3
C. P 63,698.6
B. P 13,698.6
D. P 12,940
GOOD LUCK!!!
Note: Prepare solution in separate sheet to all problem solving questions.
Question Bank in Power Plants
1.
2.
3.
4.
5.
REE Board Exam March 1998
A deep well pumps water into an open reservoir
at the rate of 100 gpm. The water table is 200 ft
below the output pipe. The system has an overall
efficiency of 70%. What shall be minimum hp of
the pump?
A. 5.3 hp
C. 12.4 hp
B. 8.7 hp
D. 7.2 hp
REE Board Exam March 1998
A pump requires 100 HP to move water with a
specific gravity of 1.0 at a certain flow rate to a
given elevation. What horsepower does the pump
require if the flow rate and elevation conditions
are the same but the fluid pumped has a specific
gravity of 0.8?
A. 80 HP
C. 60 HP
B. 100 HP
D. 120 HP
EE Board Exam April 1993
An electric motor is used to pump water from a
well of 40 ft. deep. The amount of water pumped
per hour to the ground level is 237,000 gallons.
What is the HP of the motor assuming there is no
power loss?
A. 43 HP
C. 41 HP
B. 42 HP
D. 40 HP
EE Board Exam October 1983, October 1990
A natural waterfalls 50 meters high, consistently
3
discharges 1.3 m per second. A minihydroelectric plant is to be constructed at the
bottom of the waterfalls. Calculate the electric
generator kW rating, assuming 90% mechanical
to electrical conversion efficiency and water
turbine design efficiency of 70%.
A. 401.72
C. 420.42
B. 410.55
D. 425.10
REE Board Exam March 1998
A power plant gets water from a dam from a
height of 122.45 meters at the rate of 1000 cubic
meters per minute. If the output of the plant is
15,000 kW, what is the plant efficiency?
A. 80%
C. 70%
B. 75%
D. 65%
6.
EE Board Exam April 1995
Calculate the current taken by a motor at 440 V
having an efficiency of 90%. Moreover, the motor
is used to drive a pump, which lifts 240,000 kg of
water per hour to a height of 30 meters. The
pump is given to be 80% efficient.
A. 58 A
C. 83 A
B. 75 A
D. 62 A
7.
REE Board Exam April 1994
A three-phase motor driven pump at 1,800 rpm is
discharging 500 gpm of water at a head of 25
meters. The pump efficiency is 75%. Determine
the hp of the motor.
A.
B.
15 HP
12 HP
C.
D.
14 HP
10 HP
8.
EE Board Exam April 1993
A hydroelectric station has a turbine efficiency of
80% and a generator efficiency of 85%.
Determine the volume of water required when
delivering a load of 40 MW for 6 hours if its
effective head is 120 m. Water weighs 1200
3
kg/m .
3
3
A. 899,424 m
C. 845,041 m
3
3
B. 945,352 m
D. 905,412 m
9.
EE Board Exam June 1990, April 1991
A 100 MW hydroelectric station is supplying full
load for 10 hrs in a day. Calculate the volume of
water, which has been used. Assume effective
head of the water as 200 m and the overall
3
efficiency of the station as 80%. Assume 1 m of
water = 1000 kg.
3
3
A. 2,232,435 m
C. 2,345,456 m
3
3
B. 2,293,560 m
D. 2,371,402 m
10. REE Board Exam April 1994
A waterfall is 60 meters high. It discharges at a
constant rate of 1.0 cubic meter per second. A
mini-hydroelectric plant is to be constructed
below the waterfalls. The turbine efficiency is
80% and the generator efficiency is 95%.
Calculate the kW output of the generator.
A. 447.34 kW
C. 457.27 kW
B. 464.22 kW
D. 471.30 kW
11. EE Board Exam April 1989
Maria Cristina falls located at south has a height
of 100 meters. It discharges at a constant rate of
3
2.5 m /sec. National Power Corporation has
constructed a hydroelectric plant below the water
falls. If the turbine efficiency is 70% and
generator efficiency is 90% calculate the annual
energy in kW-hr, if the discharge rate is constant
throughout the year.
Assume specific
gravity constant.
A. 13,534,857
C. 13,655,654
B. 13,467,546
D. 13,504,231
12. EE Board Exam October 1983, October 1990
A natural waterfall, 50 meters high, consistently
3
discharges 1.3 m per second. A mini
hydroelectric plant is to be constructed at the
bottom of the waterfalls. Calculate the annual
energy in kW-hr that can be generated by the
power plant. Assume turbine and generator
efficiencies equal to 70% and 90%, respectively.
A. 3,519,067
C. 3,612,212
B. 3,462,356
D. 3,345,815
13. REE Board Exam October 1997
A power plant gets water from a dam from a
height of 100 meters at the rate of 1000 cubic
meters per minute. If the over-all efficiency of the
plant is 75%, what is the kW output of the plant?
A. 7.550 kW
C. 12.262 kW
B.
15,250 kW
D.
5,250 kW
14. REE Board Exam October 1997
A power plant consumes 100,000 lbs of coal per
hour. The heating value of the coal is 12,000
BTUs per lb. The over-all plant efficiency is 30%.
What is the kW output of the plant?
A. 105,500 kW
C. 142,500 KW
B. 205,000 kW
D. 175,000 kW
15. REE Board Exam October 1998
A certain coal fire power plant has a heat rate of
6
2.88 x 10 calories per kW-hr. Coal cost
Php2,500 per ton. How much is the fuel cost
component of producing one kW-hr if the heating
value of the fuel is 13,000 BTU per lb?
A. Php2.50
C. Php1.00
B. Php1.75
D. Php1.25
16. REE Board Exam October 1997
A coal power plant has an over-all plant efficiency
of 28%. Coal with a heating value of 12,000 BTUs
per lb cost Php1.50 per lb. What is the fuel cost of
producing one kW-hr?
A. Php1.90 per kW-hr
B. Php1.75 per kW-hr
C. Php1.52 per kW-hr
D. Php1.62 per kW-hr
17. REE Board Exam April 1994
A plant has a total generating capacity of 800 kW.
The coal consumption is 1,900 lbs per hour.
Heating value of the coal is 9,500 BTU per lb.
What approximate per cent in heat in the coal is
converted into useful energy?
A. 12.3%
C. 8.7%
B. 15.0%
D. 17.5%
18. REE Board Exam October 1997
A 100 MW coal fired power plant has an average
heat rate of 9500 BTUs per kW-hr. The plant load
factor is 75%. The heating value of the coal is
12,000 BTUs per pound. Calculate the amount of
coal usage for one day.
6
A. 1.425 x 10 pounds
6
B. 2.235 x 10 pounds
5
C. 2.235 x 10 pounds
6
D. 1.826 x 10 pounds
19. REE Board Exam October 1998
A diesel generator burns fuel with a heating value
of 18,000 BTU per lb. The diesel engine has an
efficiency of 30% and the alternator has an
efficiency of 95%. Determine the fuel cost
component of producing one kW-hr if the diesel
costs Php2.80 per lb.
A. Php0.15
C. Php3.28
B. Php2.15
D. Php1.86
20. EE Board Exam April 1993
A 500 kW electric lighting cost Php1,000 per kW
installed. Fixed charges are 14%, operating cost
is Php1.50 per kW-hr. The plant averages 150
kW for 5,000 hours of the year, 420 kW for 1,000
hours and 20 kW for the remainder. What is the
unit cost production of electric energy?
A. Php1.96
C. Php2.15
B. Php1.84
D. Php2.05
21. EE Board Exam October 1989
A coal fired power plant with 3,000 kW rated
capacity costs Php15,000 per kW installed.
Annual operating cost Php12 million; annual
maintenance cost Php8 million; annual
depreciation
Php15
million;
interest
on
investment per year 8% and cost of coal Php800
per ton. If one pound of coal is needed to
generate 1 kW-hr, find the total annual cost to
operate the plant. Plant capacity factor is 50%.
A. Php46.45 million
B. Php43.38 million
C. Php40.28 million
D. Php42.32 million
22. REE Board Exam October 1998
To produce one kW-hr, a power plant burns 0.9 lb
of coal with a heating value of 13,000 BTU per lb.
What is the heat rate of the plant?
A. 6,250 BTU/kW-hr
B. 11,700 BTU/kW-hr
C. 9,500 BTU/kW-hr
D. 8,700 BTU/kW-hr
23. REE Board Exam March 1998
The current loads of four circuits are as follows:
Circuit no. 1 = 35 A
Circuit no. 2 = 46 A
Circuit no. 3 = 72 A
Circuit no. 4 = 57 A
If the diversity factor is 1.5, what is the minimum
ampacity of the feeder conductor?
A. 126 amps
C. 84 amps
B. 189 amps
D. 152 amps
24. REE Board Exam October 1998
The power customer has four circuits of 220 V,
three-phase. The circuits have maximum
demands as follows:
Circuit no. 1 = 35 A
Circuit no. 2 = 46 A
Circuit no. 3 = 72 A
Circuit no. 4 = 57 A
The diversity factor is 1.5, the load factor is 50%,
and the power factor is 80%. What is the
maximum kVA demand of the customer?
A. 46 kVA
C. 80 kVA
B. 26.5 kVA
D. 53 kVA
25. EE Board Exam April 1980
A substation transformer is serving the following
loads:
Demand
Classification
Total Load
Factor
Lighting
300 kW
60%
Power
1200 kW
80%
Heating
500 kW
90%
If the diversity factor among the load types is 1.5,
determine the maximum demand on the
transformer.
A. 2000 kW
C. 1225 kW
B. 1060 kW
D. 1180 kW
26. REE Board Exam October 1998
The power customer has four circuits of 220 V,
three-phase. The circuits have maximum
demands as follows:
Circuit no. 1 = 35 A
Circuit no. 2 = 46 A
Circuit no. 3 = 72 A
Circuit no. 4 = 57 A
The diversity factor is 1.5, the load factor is 50%,
and the power factor is 80%. What is the
approximate kW demand of the customer?
A. 15 kW
C. 21 kW
B. 43 kW
D. 53 kW
efficiency of 30% and the generator has an
efficiency of 95%. Compute the fuel cost of
producing one kW-hr if the fuel costs Php6.00 per
liter. Given the density of the fuel as 900 grams
per liter.
A. Php5.00
C. Php3.00
B. Php2.00
D. Php1.00
32. REE Board Exam October 1998
A 100 MW power plant has a heat rate of 2.88 x
106 calories per kW-hr. It is a base load plant and
runs at full load 24 hrs a day. How many tons of
coal is needed per day if its heating value is
13,000 BTU per lb?
A. 250
C. 830
B. 625
D. 960
27. EE Board Exam April 1990
A certain power plant has a reserve capacity
above the peak load of 10 MW. The annual
factors are load factor = 59%, capacity factor =
41% and use factor = 46%. Determine the
installed capacity.
A. 33.45 MW
C. 32.77 MW
B. 31.85 MW
D. 30.47 MW
33. REE Board Exam September 2000
The following are the given loads of a particular
circuit:
5 - 15 HP motors
3 - 5 HP motors
8 kW - lighting loads
3.5 kW - miscellaneous loads
Calculate the maximum demand if the demand
factor is 65%.
A. 78.64
C. 51.12
B. 45.81
D. 120.98
28. EE Board Exam April 1990
A certain power plant has a reserve capacity
above the peak load of 10 MW. The annual
factors are load factor = 59%, capacity factor =
41% and use factor = 46%. Determine hours per
year not in service.
A. 952 hours
C. 924 hours
B. 965 hours
D. 937 hours
34. EE Board Exam October 1994
Power plant curves or graphs showing the direct
relationships of the peak load and the generated
energy of the said plant is
A. load curve/graph
B. load duration curve
C. modified load curve
D. none of the above
29. EE Board Exam April 1993
A central generating station has an annual factor
report as follows:
Plant Capacity Factor = 50%
Load Factor = 60%
Use Factor = 45%
Reserved = 10,500 kW
Determine the rated capacity of the station.
A. 63,000 kW
C. 65,000 kW
B. 60,000 kW
D. 70,000 kW
35. REE Board Exam March 1998
In fission, energy is produced when
A. chemical compound split into its constituents
B. nuclear particles combine
C. nuclear particles split
D. molecules combine
30. REE Board Exam October 1998
The metering of a power substation was read and
gave the following data:
kW-hr = 200,000
kVAR-hr = 180,000
Maximum Demand = 380 kW
Billing days = 30
What is the load factor?
A. 68%
C. 80%
B. 73%
D. 62%
31. REE Board Exam September 2000
A diesel generator set burns fuel with a heating
value of 18,000 BTU per lb. The engine has an
36. REE Board Exam March 1998
In the list below, which one is not a type of
present day nuclear power plant?
A. boiling water reactor
B. fusion-fission reactor
C. low pressure reactor
D. fast breeder reactor
37. REE Board Exam October 1997
The energy of present nuclear plants comes from
A. the fusion of radio active materials
B. the friction of high speed electrons against
protons
C. the destruction of very tiny particles released
when atoms split
D. the heat produced by the collision of high
speeed protons
38. REE Board Exam October 1997
The ratio of the average load on the plant for the
period of time considered to the aggregate rating
of all the generating equipment
A. capacity factor
B. load factor
C. utilization factor
D. diversity factor
Unsolved problems
39. REE Board Exam April 1997
An effective removes of dust, carbon particles
and other from the flue gas of the power plant is
called
A. electrostatic precipitator
B. soot blower and collector
C. mechanical collector
D. dust scrubber
40. EE Board Exam April 1990
A thermal power plant using dry organic material
such as wood and other wastes for its fuel
A. geothermal power plant
B. diesel power plant
C. dendro power plant
D. hydro power plant
41. REE Board Exam April 1994
Type of water wheels used in hydraulic plants
A. propeller
C. reaction
B. impulse
D. all of these
42. REE Board Exam April 2001
A hydroelectric plant generates 100 MW at an
available head of 200 m and an overall efficiency
of 75%. What quantity of water in cubic meter per
second is required?
A. 1,200
C. 26
B. 122
D. 68
43. REE Board Exam October 1998
A ten year investigation of rivers potential gave
an average water flow of 25 cm per second at the
bottom and 90 cm per second at the surface. The
average cross section at the same location is 80
sq m. What is the average flow rate in cubic
meter per hour?
A. 165,600
C. 46,500
B. 57,600
D. 5,760
BTU per lb cost Php1.50 per lb. What is the fuel
cost of producing one kW-hr?
A. Php1.90 per kW-hr
B. Php1.75 per kW-hr
C. Php1.52 per kW-hr
D. Php1.62 per kW-hr
46. REE Board Exam October 2000
A diesel power plant has an overall efficiency of
30%. If the calorific value of diesel is 18,000
BTU/lb and cost Php6.00 per liter, how much is
the fuel cost of production per kW-hr of energy?
Take the density of diesel as 900 grams per liter.
A. Php1.91 per kW-hr
B. Php1.85 per kW-hr
C. Php2.12 per kW-hr
D. Php2.45 per kW-hr
47. REE Board Exam October 1998
The feedwater is usually heated before it is
injected to the boiler for the following reason
except one. Which one is this?
A. improves the overall performance of the
plant
B. recovers part of the flue gas heat which is
otherwise lost to the atmosphere
C. derating types of preheaters permit the
removal of dissolved gases from the
feedwater
D. increases the efficiency of the boiler
48. REE Board Exam October 1998
A proposed hydroelectric station has an available
6
head of 30 m, a catchment area of 50 x 10 sq m,
the rainfall for which is 120 cm per annum. If 70%
of the total rainfall can be collected, calculate the
power that can be generated. Assume the
following efficiencies: Penstock 95%, Turbine
80% and Generator 85%.
A. 253 kW
C. 214 kW
B. 678 kW
D. 925 kW
49. While calculating the cost of electric power
generation, which of the following is NOT
considered a fixed cost?
A. interest on capital investment
B. taxes and insurance
C. most of the salaries and wages
D. repair and maintenance
44. REE Board Exam September 2002
A power plant is driven by turbine at a rate of 10
cubic meters per second and with a head of 235
m. If the plant efficiency is 0.65, calculate the
power plant output.
A. 10,000 kW
C. 35,000 kW
B. 15,000 kW
D. 25,000 kW
50. Maximum demand of an installation is given by its
A. instantaneous maximum demand
B. greatest average power demand
C. average maximum demand over a definite
interval of time during a certain period
D. average power demand during an interval of
1-minute
45. REE Board Exam October 1997
A coal power plant has a boiler, turbine and
alternator efficiencies of 35%, 86% and 93%
respectively. Coal with heating value of 12,000
51. A diversity factor of 2.5 gives a saving of ____
percent in the generating equipment.
A. 60
C. 40
B. 50
D. 25
52. Mark the WRONG statement. High load factor of
a generating equipment
A. leads to lesser charges per kWh
B. implies lower diversity in demand
C. gives more profit to the owner
D. can be obtained accepting off-peak loads
53. In a generating station, fixed, charges at 100%
load factor are 6 paisa/kWh. With 25% load
factor, the charges would become ____
paisa/kWh.
A. 1.5
C. 24
B. 10
D. 3
54. When considering the economics of power
transmission, Kelvin’s law is used for finding the
____
A. cost of energy loss in bare conductors
B. most economical cross-section of the
conductors
C. interest on capital cost of the conductor
D. the maximum voltage drop in feeders
55. A 3-phase balance system working at 0.9 lagging
power factor has a line loss of 3600 kW. If p.f. is
reduced to 0.6, the line loss would become ____
kW.
A. 8100
C. 5400
B. 1600
D. 2400
56. Mark the WRONG statement. While considering
power factor improvement, the most economical
angle of lag depends on the ____
A. cost/kVA rating of phase advancer
B. rate of interest on capital outlay
C. rate of depreciation
D. value of original lagging p.f. angle
57. EE Board Exam October 1990
A 55,000 kW thermal plant of National Power
Corporation delivers an annual output of
238,000,000 kW-hr with a peak load of 44 MW.
What is the capacity factor?
A. 49.4%
C. 48.2%
B. 42.4%
D. 44.6%
58. A deep well pumps water into an open reservoir
at rate of 150 gpm. The water table is 200 ft
below the output pipe. The whole system has an
overall efficiency of 80%. What shall be the
minimum hp of the pump?
A. 9.45 hp
C. 5.12 hp
B. 7.15 hp
D. 8.53 hp
59. Which of the following is least efficient?
A. Diesel Gen-Set
B. Combined Gen-Set
C. Gasoline Gen-Set
D. Coal Power Plant
60. An industrial load of 25 kVA has an overall power
factor of 0.8 lagging. A group of resistance
heating unit was installed and the plant power
factor is found to be 0.895 lagging. What kW of
resistance heating unit was installed?
A. 4.3 kW
C. 5.3 kW
B. 3.4 kW
D. 6.4 kW
61. What do you mean by “demand” of the customer?
A. Voltage need
B. Voltage, frequency, phase need
C. Voltage, frequency need
D. kVA load
62. Fusion energy is produced when
A. chemical compounds combined
B. fuel burns
C. nuclear particle divides
D. nuclear particle combined
63.
A.
B.
C.
D.
A.
B.
C.
D.
64.