AREA 3 Flashcards

1
Q

An international agreement which embodies the Clean Development Mechanism or CDM.

A. Geneva Convention B. International Treaty C. Tokyo Protocol D. Kyoto Protocol

A

Answer: D

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2
Q

n what year will the Kyoto Protocol expire?

A. 2011 B. 2012 C. 2015 D. 2020

A

Answer: A

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3
Q

Renewable Energy Act of 2008 is also known as

A. RA 9367 B. RA 9513 C. RA 8559 D. RA 8435

A

Answer: B

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4
Q

Biofuels Act of 2006 is also known as

A. RA 9367 B. RA 9513 C. RA 8559 D. RA 8435

A

Answer: A

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5
Q

What energy generating plant does not use turbine for power generation?

A. Hydro B. Geothermal C. Ocean-thermal D. Biogas plant

A

nswer: D

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6
Q

From the BiGSHOW acronym of renewable energy coverage, what “Bi” stands for?

A. Biomass B. Biofuel C. Biomass and biofuel D. Biodiesel

A

Answer: C

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7
Q

Aerogenerator, covered lagoon biodigester and minihydro energy projects are evaluated for
financial feasibility. Only one feasible project can be funded. Each project needs PHP 30M
investment. The financial internal rate of returns are 11%, 8% and 9%, respectively. Annual
discount plus inflation rate is 12%. Which of the 3 projects shall be implemented?

A. Aerogenerator B. Covered lagoon biodigester C. Minihydro D. None

A

Answer: D (since all their IRRs are less than the discount plus inflation rate)

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8
Q

An Ocean Thermal Energy Conversion (OTEC) project was evaluated for financial
feasibility. At 12% annual discount rate, it has the following feasibility indicators: net present
value of 2.5 billion pesos and internal rate of return of 60%. If annual discount rate drops to
10%, will the project still be feasible?

A. No B. Yes C. Maybe D. Insufficient data to determine

A

Answer: B (if it is feasible at 12% discount rate, the more it will be feasible at 10%)

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9
Q

What part of solar module should be included such that solar charging is continuous at
slower rate even when partially shaded by trees?

A. Blocking diode B. Bypass diode C. Shading diode D. Lightning diode

A

Answer: B

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10
Q

What diode is needed as protection against lightning in solar installations?

A. Blocking diode B. Bypass diode C. Shading diode D. Lightning diode

A

Answer: A

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11
Q

What pin is common in integrated circuits (ICs).

A. +12 Vdc input B. +5 Vdc output C. Ground D. Binary output

A

nswer: C

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12
Q

A kind of IC included as an important part of electronic instruments for gathering speed,
velocity and discharge real-time data.

A. Voltage reducer B. Timer C. Sensor D. Variable resistor

A

Answer: B

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13
Q

Which one is an integrated circuit (IC) used in instrumentation and control?

A. TD 8062 B. ES 8813 C. CQ 556 D. LM 333

A

Answer: D

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14
Q

Which DC voltage is best for remote instrumentation?

A. 5, 7 or 9 Vdc B. 5 Vdc C. 7 Vdc D. 9 Vdc

A

Answer: A

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15
Q

Transmission of data to a remote line-of-sight point is best done using

A. Fiber optics B. Fax C. E-mail D. Radio frequency

A

Answer: D

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16
Q

. To automate control of irrigation dam gates, what switch is useful in the instrumentation?

A. Automatic transfer switch B. Pressure switch C. Power switch D. Time switch

A

Answer: A

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17
Q

A switch for automatic starting of pumps with sealed water tank in drip irrigation systems.

A. Automatic transfer switch B. Pressure switch C. Power switch D. Time switch

A

Answer: B

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18
Q

What part of an aerogenerator exceeding 100 kw capacity is responsible in converting
rotational movement to electricity?

A. Alternator B. Turbine C. Rotor D. Governor

A

Answer: A

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19
Q

The component of force used to rotate the rotor in multi-bladed windmills.

A. Drag force B. Lift force C. Side force D. Drop force

A

Answer: B

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20
Q

The component of force used to rotate the rotor in savonius windmills.

A. Drag force B. Lift force C. Side force D. Drop force

A

Answer: A

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21
Q

What type of pump is appropriate for multi-bladed windmills?

A. Hydraulic B. Diaphragm C. Pneumatic D. Reciprocating

A

Answer: D

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22
Q

What efficiency can exceed 100% while the windmill is in operation?

A. Transmission B. Volumetric C. Rotor D. Crank

A

Answer: B

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23
Q

A wind energy resource located about 10-16 km from Earth surface with velocity over 150
kph

A. Terrestrial wind B. Extra-terrestrial wind C. High wind D. Jet stream

A

Answer: D

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24
Q

Part of multi-bladed wind pump which is responsible in converting rotational movement to
reciprocating action.

A. Rotor B. Reciprocating pump C. Connecting rod D. Crank arm

A

Answer: C

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25
Q

Which type of multi-bladed wind pump tail is more effective for windy areas?

A. Ecliptic B. Hinged side vane C. Manual folding D. No tail

A

Answer: B

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26
Q

n big wind farm projects, which should be done first?

A. Rotor B. Transmission C. Wind velocity measurement D. Energy demand survey

A

Answer: C

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27
Q

In multi-bladed wind mill fabrication, what should be done first?

A. Rotor blade B. Rotor frame C. Jig D. Tower

A

Answer: C

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28
Q

To increase water displacement volume in wind mills, what part should be increased?

A. Connecting rod length B. Rotor diameter C. Well diameter D. Crank arm

A

Answer: D

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29
Q

To have a tip speed ratio of 1:1 in windmills, what should be the average rotor blade twist
angle in degrees?

A. 75 B. 60 C. 45 D. 30

A

Answer: C

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30
Q
  1. If typical overall efficiency of multi-bladed windmills is 8-16%, what is the typical overall
    efficiency of manufactured aerogenerators or electricity generating windmills?

A. 90-95% B. 18-21% C. 15-17% D. 7-10%

A

Answer: A

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31
Q

If a wind mill rotor has a tip-speed ratio of 1:1, what windspeed is required for its rotor tip
to move at 3.3 m/s?

A. 1 m/s B. 1 ft/s C. 3.3 m/s D. 3.3 ft/s

A

Answer: C
\Solution:
Windspeed = tip speed, since tip-speed ratio is 1:1
= 3.3 m/s

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32
Q

. An 4-bladed windpump with 7 meters rotor diameter and 45 degrees twist angle is to be
modified due to insufficient starting torque. What should be done?

A. Increase twist angle B. Increase blades C. Decrease blades D. Decrease twist angle

A

Answer: B (since increasing blades increases torque)

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33
Q

. A windpump having 8 meters rotor diameter, 6 cm pump diameter and 2.2 cm crank arm is to
be modified due to low volumetric efficiency. What should be done?
A. Enlarge rotor B. Reduce rotor C. Enlarge pump diameter D. Elongate crank arm

A

Answer: D
(Note: Elongating crank arm increases pump stroke and volumetric efficiency)

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34
Q

. A 3-bladed 50-meter tall aerogenerator with 25 meters rotor radius designed for 6.2 m/s wind
can’t rotate. Average windspeed at rotor center is 6 m/s. Which part needs to be increased?
A. Number of blades

B. Rotor radius
C. Tower height
D. Crank arm

A

Answer: C
(Note: Windspeed is higher at higher elevation; increasing rotor radius will severely affect
twist angle of entire blade & tip-speed ratio; aerogenerators have no crank arm)

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35
Q
  1. What is the electrical energy consumption of a 30-kw vermicast production shredder plugged
    in a 240-volt source if it requires 1 hour to shred 2 tonnes of farm waste?
    A. 0.02 kwh/kg
    B. 0.015 kwh/kg
    C. 0.06 kwh/kg
    D. 0.08 kwh/kg
A

Answer: B Solution:
Ec = PcTo / Wi
B. 0.015 kwh/kg
= 30 kw (1 h) / 2,000 kg
= 0.015 kwh/kg

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36
Q

Battery appropriate for slow charging and slow discharging energy systems?

A. Maintenance-free battery B. Automotive battery C. NiCad Battery D. Solar battery

A

Answer: D

37
Q

Kind of battery useful in solar home systems.

A. Sealed lead-acid battery B. Automotive battery C. All lead-acid batteries C. Solar battery

A

Answer: C

38
Q

. Photovoltaic conductor material used in manufacturing solar modules.

A. Silicon B. Boron C. Silicon with little boron D. Equal silicon and boron

A

Answer: C

39
Q

During a clear sky noontime in the Philippines, what is the possible voltage reading of solar
pump without battery when electrical load is in switched on?

A. 11-13 V B. 14-15 V C. 16-19 V D. 20-22 V

A

Answer: C

40
Q

During a clear sky noontime in the Philippines, what is the possible voltage reading of solar
battery charger when no battery is being charged?

A. 11-13 V B. 14-15 V C. 16-19 V D. 20-22 V

A

Answer: D

41
Q

During 8:00 P.M. in the Philippines, what is the possible system voltage reading of a solar
home system when all electrical loads are switched on?

A. 11-13 V B. 14-15 V C. 16-19 V D. 20-22 V

A

Answer: A

42
Q

. During solar panel installation, which positive polarity wire should be connected last to the
battery control unit (BCU)?

A. Solar module B. Battery C. Load D. Monitor

A

Answer: B

43
Q

When a bamboo shades half of solar module, which condition is true?

A. Zero voltage B. Low voltage C. Low amperage D. Zero amperage

A

Answer: C

44
Q

How do you classify a 260 kw hydro power plant?

A. Microhydro B. Small hydro C. Minihydro D. Big hydro

A

Answer: C

45
Q

Using Philippine classification, specify the maximum power rating for microhydro?

A. 100 kw B. 75 kw C. 50 kw D. 25 kw

A

Answer: A

46
Q

The geothermal power system resembles in principle to a

A. Hot air balloon B. Gas pump C. Jet propulsion D. Kettle

A

Answer: D

47
Q

Which stage comes first in a geothermal power plant development?

A. Drilling B. Geophysical survey C. Energy demand survey D. Chemical test

A

Answer: B

48
Q

otating part of a geothermal power plant which moves the generator.

A. Rotor B. Rotator C. Motor D. Turbine

A

Answer: D

49
Q

The Ocean Thermal Energy Conversion (OTEC) operating principle resembles a

A. Refrigerator B. Gasoline engine C. Hydro power plant D. Water tank

A

Answer: A

50
Q

In an Ocean Thermal Energy Conversion (OTEC) system, what causes OTEC fluid to flow
and rotate the turbine?

A. Bouyancy B. Fluid pressure C. Underwater current D. Temperature difference

A

Answer: D

51
Q
  1. Which one is not a form of ocean energy.

A. Wave B. Tidal C. Transtidal D. Thermal

A

Answer: C

52
Q

In the factory, bottling of virgin coconut oil prints batch numbers. What is the main purpose
of batch numbers?

A. Serial number B. Bottle identification C. Product recall D. Expiry indicator

A

Answer: C

53
Q

Which one is not a part of a vertical feed mixer?

A. Screw B. Hopper C. Conveyor D. Discharge chute

A

Answer: C

54
Q

Feed mixers evaluated to have 10-15% mixing coefficient of variation is rated as

A. Very good B. Good C. Fair D. Poor

A

Answer: B

55
Q

Based on standards, the minimum stripping efficiency of the mechanized stripping machine
shall be

A. 90% B. 85% C. 80% D. 70%

A

Answer: C

56
Q

A 2.8-tonne capacity Jatropha oil expeller was loaded full with dried Jatropha seeds in 3
minutes. It produced 900 kg of crude oil in 2 hours. What is its crude oil production rate?

A. 300 kg/h B. 450 kg/h C. 600 kg/h D. 300 kg/min

A

Answer: B

Solution:

Poil = Weight of crude oil collected / Total time
= 900 kg /2 h
= 450 kg/h

57
Q

A Jatropha oil expeller was loaded with 2.2 tonnes dried Jatropha seeds. It produced 600 kg
of crude oil in 4 hours. What is its Jatropha cake production rate?

A. 700 kg/h B. 500 kg/h C. 400 kg/h D. 300 kg/h

A

Answer: C

Solution:

Pcake = Weight of resulting Jatropha cake produced / Total time
= (2,200 kg seed - 600 kg oil) /4 h
= 400 kg/h

58
Q

A 21-tonne capacity coconut oil expeller was loaded full with grated copra. It produced 7,000
kg of crude oil in 20 hours. What is the copra cake production rate of the machine at 95%
cake collection efficiency?
A. 700 kg/h

B. 665 kg/h
C. 588 kg/h
D. 885 kg/h

A

Answer: B
Solution:
Pcake = [(Wt. of copra input - Wt. of crude oil collected )/ Total time] x Eff
= [(21,000 kg - 7,000 kg) /20 h] x 0.95
= 665 kg/h

59
Q

How many tonnes of agricultural waste is needed annually to optimally operate a 25-ampere
5-kw vermicast production shredder having a capacity of 0.2 tonne of waste per hour? It
optimally operates 16 hours daily during the 3-month peak sunny months and 8 h/day at 26
days/month for the rest of the year.
A. 3312

B. 662
C. 1440
D. 1872

A

Answer: B
Solution:
Wt = Input Rate x (Peak Operating Time + Lean Operating Time)
= [0.2 tonne/h][ (16 h/d x 30 d/mo x 3 mo/yr)+ (8 h/d x 26 d/mo x 9 mos/yr)]
= 662 tonnes /yr

60
Q

What is the standard diameter of both vertical and horizontal reinforcing bars in open channel
construction?

A. 16 mm B. 12 mm C. 10 mm D. 8 mm

A

Answer: C

61
Q

What class of concrete mix should be used in open channel construction?

A. Class AA B. Class A C. Class B D. Class C

A

nswer: B

62
Q

What is the standard spacing between vertical bars in open channel construction?

A. 20 cm B. 25 cm C. 30 cm D. 50 cm

A

Answer: A

63
Q

What is the standard concrete wall thickness of lateral trapezoidal open channel in open
channel design?

A. 5 cm B. 10 cm C. 12 cm D. 15 cm

A

Answer: D

64
Q

The appropriate gage number of galvanized iron (GI) tie wire for open channel construction.

A. 10 B. 12 C. 16 D. 18

A

Answer: C

65
Q
  1. When using class A, B or C concrete mix, how many cubic meters of sand should be mixed
    to produce one cubic meter concrete?

A. 0.25 B. 1.0 C. 0.75 D. 0.50

A

Answer: D

66
Q

How many 40-kg bags of cement are needed per cubic meter concrete in standard (Class A)
open channel construction?

A. 6 B. 7.5 C. 9 D. 12

A

Answer: C

67
Q

In open channel construction, how many 40-kg bags of cement are needed for a 20-km lateral
channel if it requires 0.6 cubic meter concrete per linear meter? Use 5% safety factor.

A. 108,000 B. 114,300 C. 180,000 D. 113,400

A

Answer: D

Solution:

Bags = Safety factor x Bags cement/cu.m. concrete x Concrete volume/m x m length
= 1.05 x 9 bags/cu.m. x 0.6 cu.m/m x 20,000 m
= 113,400 bag

68
Q

How many truck loads of sand are needed for 50-km main irrigation canal requiring 3.5 cubic
meters concrete per linear meter? 1 truck load is 2.5 cubic meters. Use 5% safety factor.

A. 36,750 B. 35,000 C. 36,570 D. 53,000

A

Answer: A

Solution:

Truck loads = Safety factor x Cu.m. sand/cu.m. concrete x Trucks/cu.m. x Concrete volume
= 1.05 x 0.5 cu.m./cu.m. x 1 truck load/2.5 cu.m. x (3.5 cu.m/m x 50,000 m)
= 36,750 truck loads

69
Q

Estimate the truck loads of gravel needed for an 8-km main irrigation canal requiring 4 cubic
meters concrete per linear meter. 1 truck load is 2.5 cubic meters. Use 10% safety factor.

A. 12,800 B. 18,200 C. 14,080 D. 14,800

A

Answer: C

Solution:

Truck loads = Safety factor x Cu.m. gravel/cu.m. concrete x Trucks/cu.m. x Concrete volume
= 1.1 x 1 cu.m./cu.m. x 1 truck load/2.5 cu.m. x (4 cu.m/m x 8,000 m)
= 14,080 truck loads

70
Q

How much should be budgeted for cement for 20-km irrigation canal if it requires half cubic
meter concrete per linear meter and cement costs Php210/bag? Use 5% safety factor.

A. Php 18,900,000 B. Php 19,845,000 C. Php 19,800,000 D. Php 18,945,000

A

Answer: B

Solution:

Budget = Safety factor x Bags cement/cu.m. concrete x Concrete volume x Unit Cost
= 1.05 x 9 bags/cu.m. x (0.5 cu.m/m x 20,000 m) x Php 210
= Php 19,845,000

71
Q

A gravity dam weighing 75,000 tonnes is to be constructed with length along dam axis of 1
km and base of 100 meters. What should be the minimum soil bearing stress? Use factor of
safety against sinking of 2.
A. 1.5 tonnes/sq.m.
B. 0.75 tonnes/sq.m.
C. 7.5 tonnes/sq.m.
D. 5.1 tonnes/sq.m

A

Answer A

inking Factor of safety = Min. defensive bearing stress/Offensive bearing stress
Min. def. stress = Sinking FS x Offensive Stress, Offensive stress = Weight/Area
= 2 x (75,000 tonnes / (1,000 m x 100 m)
= 1.5 tonnes/square meter

72
Q

Give cement budget estimate for 10-km canal requiring 2/3 cubic meter concrete per linear
meter. Cement costs Php200/bag while transport costs Php 10/bag. Use 5% safety factor.
A. Php 13,236,615

B. Php 12,606,300
C. Php 12,300,606
D. Php 13,615,236

A

Answer: A
Solution:
Budget = Safety factor x Bags cement/cu.m. concrete x Concrete volume x Unit Cost
= 1.05 x 9 bags/cu.m. x (0.667 cu.m/m x 10,000 m) x (Php 200 + Php 10)
= Php 13,236,615

73
Q

A gravity dam weighing 75,000 tonnes is to be constructed with length along dam axis of 1
km and base of 100 meters. What should be the minimum soil bearing stress? Use factor of
safety against sinking of 2.
A. 1.5 tonnes/sq.m.
B. 0.75 tonnes/sq.m.
C. 7.5 tonnes/sq.m.
D. 5.1 tonnes/sq.m

A

Answer A

inking Factor of safety = Min. defensive bearing stress/Offensive bearing stress
Min. def. stress = Sinking FS x Offensive Stress, Offensive stress = Weight/Area
= 2 x (75,000 tonnes / (1,000 m x 100 m)
= 1.5 tonnes/square meter

74
Q

A 2-meter thick trapezoidal section of a concrete dam has resisting moment about the dam
toe of 350,000 tonne-meters. The water exerts 4,050 tonnes horizontally at 30 meters above
the dam toe. What is the factor of safety against overturning?
A. 8.22

B. 1.80
C. 2.88

D. 2.08

A

Answer: C
Solution: Overturing Factor of Safety = Resisting moment/Overturning moment
= 350,000 /(4050 x 30)
= 2.88

75
Q

. A concrete dam with 60,000 sq.m. submerged vertical upstream wall is to be constructed
against a 546 tonnes/sq.m. average water pressure. Coefficient of friction at dam base is 0.8.
What should be the minimum dam weight? Use factor of safety against sliding of 2.
A. 65,520,000 tonnes B. 81,900,000 tonnes C. 65,520 tonnes D. 81,900 tonnes

A

Answer: B
Solution:
SlidingFactor of Safety = Min. defensive horizontal force/Offensive horizontal force
Min. defensive force = Coef. of friction x Weight = FS x Offensive force
Weight = FS x Offensive force / Coef. of friction
Weight = 2 x (546 tonnes/sq.m. x 60,000 sq.m.) / 0.8
Weight = 81,900,000 tonnes

76
Q

Value of fee to project owners from Clean Development Mechanism (CDM) fund for carbon
emission reduction projects.

A. Emission value B. Carbon credit value C. Carbon trading value D. Carbon sequestration

A

Answer: B

77
Q

What is the acronym for the Inter-Governmental Panel for Climate Change?

A. IGPFCC B. IGPCC C. IPCC D. IPFCC

A

Answer: C

78
Q

Best type of biogas plant for large-scale animal farms having low solid content of effluents.

A. Fixed dome B. Floating type C. Tube-bag D. Covered lagoon

A

Answer: D

79
Q

. Kind of plastic sheet for constructing balloon and bed lining in covered lagoon biogas plants.

A. Acetate B. Polyvinyl Chloride (PVC)
C. Linear low density polyethylene (LLDPE) D. High density polyethylene (HDPE)

A

Answer: D

80
Q

In the environment, by how many times is methane destructive than carbon dioxide?

A. 2 times B. 21 times C. 10 times D. 16 times

A

Answer: B

81
Q

The toxic gaseous by-product of geothermal power plants that is trace in biogas.

A. Carbon monoxide B. Hydrogen sulfate C. Hydrogen sulfide D. Sulfuric acid

A

Answer: C

82
Q

In covered lagoon biodigester where solids is less than 3%, what is approximate methane
content in biogas?

A. 40% B. 50% C. 60% D. 70%

A

Answer: D

83
Q

If water-manure ratio is 1:1, what is the approximate methane content of biogas?

A. 40% B. 60% C. 70% D. 50%

A

Answer: B

84
Q

The minimum methane content of biogas such that biogas-fueled generators will run.

A. 50% B. 85% C. 65% D. 75%

A

Answer: C

85
Q

Determine the daily biogas consumption in cubic meters of an industrial boiler using 5 units
of 50-cm gas burner 8 hours a day. The consumption of each gas burner is 1.2 cu.m./hour.
A. 48
B. 84
C. 40
D. 80

A

Answer: A
Solution:
C = NBT
where C= Consumption, N = No. of units, B = biogas consumption of device, T = Time
C = (5 units)( 1.2 m3/hr)(8 hrs)
= 48 m3

86
Q

Estimate the biogas production in cubic meters per day from a large balloon type digester
using 1:1 water-manure ratio. The source farm has 2,000 heads of porkers of mixed ages. Use
a retention period of 30 days. The mean daily manure production of porkers is 2.2 kg/head
while the specific gas production for 30-day manure retention period is 0.063 m3/kg.
A. 4,400
B. 126
C. 162
D. 277

A

Answer: D
Solution:
P = NMG
B. 126
C. 162
D. 277
where P = biogas production potential, N = No.of heads, M = manure production,
G = Specific gas production of the manure for a specific retention period
P = (2000 heads)(2.2 kg/head)(0.063 m3/kg)
= 277.2 m3

87
Q

How many heads of breeding cattle are needed as source of manure to generate 85 m3 of
biogas a day if the retention period is 25 days and water-manure ratio is 1:1. The mean daily
manure production of breeding cattle is 13 kg/head while its specific gas production for 25
day manure retention period is half of that of chicken dung.
A. 33
B. 7
C. 218
D. 34

A

Answer: C
Solution:
N = P/(MG)
where N = No. of heads, C = biogas production, M = manure production,
G = Specific gas production of the manure for a specific retention period
G = 0.5 x G for chicken dung at 25-day retention period
= 0.5 x 0.06 m3/kg
= 0.03 m3/kg
C = (85 m3)/[(13 kg/head)(0.03 m3/kg)]
= 217.9 heads, to avoid gas shortage round up to 193 heads

88
Q

When approved as Clean Development Mechanism (CDM) project, how much will the
project owner of a new covered lagoon biodigester receive annually from CDM fund for the
first 10 years if the digester produces 7,000 tonnes of methane plus 3,000 tonnes of carbon
dioxide annually. Assume current carbon credit costs US$12 per tonne of carbon equivalent.
A. US$ 1,800,000
B. US$ 120,000
C. US$ 1,200,000
D. US$ 204,000

A

Answer: A
Solution:
Considering that methane is 21 times more destructive than carbon,
Amount = Carbon cost per tonne x [(tonnes carbon/year + 21 (tonnes of methane/year)]
= US$ 12 [3,000 + 21(7,000)]
= US$ 1,800,000/yea