WorksheetsSolar Math - Revisited - 03312025
Total questions: 37
Worksheet time: 20mins
The minimum temperature for a location is 7°C. What is the difference between that and the standard test condition
temperature of 25°C?
-32°C
18°C
-18°C
32°C
The current temperature is 19°C and the minimum temperature for a location is -22°C.
What is the difference between the minimum and standard test condition temperature of 25°C?
-47°C
-3°C
47°C
6°C
Calculate the cost per watt of a 7,600 W system with a total cost of $24,472.
$3.15
$3.22
$3.10
$3.47
Calculate the cost per watt of a 5.5 MW (megawatt) system with a gross cost of $6,050,000.
$1.15
$1.10
$0.90
$0.95
Put the following mathematical operations in the correct order:
Parenthesis
Exponents
Multiplication/
Division
Addition/
Subtraction
Solve the following equation:
36.8 V x [100% + ((30°C + 41°C – 25°C) x -0.41%/°C)]
39.04 V
35.29 V
31.45 V
29.86 V
Convert -0.36% to a decimal.
0.0036
-3.60
0.036
-0.0036
Convert 155% to a decimal.
1.55
15.5
0.155
0.0155
Convert 26 to a percentage.
260%
2.6%
0.26%
2600%
An 8.4 kilowatt (kW) PV array is connected to an inverter with a 93% efficiency rating.
What would be the approximate output
at STC
(Standard Test Conditions)?
781.2 kW
7,812 kW
7.812 kW
78.12 kW
8.2 kWh are charged into a battery with an overall 75% efficiency rating. Approximately how many kWh would you expect
to get out of the battery?
5.95 kWh
6.83 kWh
7.35 kWh
6.15 kWh
Calculate the area of a roof surface that is 35.8 feet wide by 22.3 feet long.
804.7 ft²
787.2 ft²
798.3 ft²
794.3 ft²
Calculate the area of a roof surface that is 12.9 meters wide by 7.5 meters long.
95.67 m²
96.42 m²
96.75 m²
98.64 m²
Calculate the area of a triangular roof with a base width of 35.75 feet and a height of 23.325 feet.
417.2 ft²
845.6 ft²
416.9 ft²
833.9 ft²
Calculate in square feet the area of a triangular roof with a base width of 330” and a height of 159”.
182.2 ft²
1184.3 ft²
364.4 ft²
382.7 ft²
Calculate the square meter area of a triangular roof
with a base width of 1934 cm and a height of 1356 cm.
131.1 m²
13.11 m²
1.311 m²
1311 m²
A PV array is producing 125,352 watts.
Is this an example of power or energy?
Power
Energy
A battery has a capacity of 14 kilowatt-hours (kWh).
Is this an example of power or energy?
Energy
Power
If a 1,400 W electric heater runs continuously for four hours,
how much energy does it consume?
1,400 Wh
5,600 W
1,400 W
5,600 Wh
While running, a 24 VDC refrigerator consumes 25 amps.
How much power does it use?
600 Wh
1,800 W
1,200 Wh
600 W
If a 1.5 A, 120 V light is left on in the barn for 12 hours,
how much energy will it use?
2.16 Wh
2,160 kWh
2,160 kW
2.16 kWh
Calculate the cost per watt of a 150 kW (kilowatt) system with a gross cost of $199,500.
$0.85
$0.75
$1.33
$1.10
Calculate the cost per watt of a 4.5 kW battery backup system with a gross cost of $18,450.
$2.43
$2.95
$3.22
$4.10
Solve the following equation: 43.8 V x [100% + ((-14°C – 25°C) x -0.34%/°C)]
49.61 V
53.76 V
47.53 V
44.80 V
Solve the following equation: 55.3 V x [100% + ((2°C – 25°C) x -0.39%/°C)]
59.59 V
58.73 V
60.26 V
61.29 V
15 kWh are charged into a battery with an overall 86% efficiency rating.
Approximately how many kWh would you expect to get out of the battery?
17.4 kWh
12.9 kWh
13.2 kWh
11.7 kWh
A 235 kW PV array is connected to an inverter with a 96% efficiency rating.
What would be the approximate output at STC?
224.8 kW
227.7 kW
232.4 kW
225.6 kW
A computer is used for 8 hours and consumes 384 watt-hours.
What is its power rating?
128 Watts
48 Watts
96 Watts
38.4 Watts
A toaster is rated at 1,300 watts at 120 volts AC. How much current does it draw?
9.2 A
10.8 A
9.9 A
11.4 A
A well pump is rated for 17 A and 4,080 W.
At what voltage does it operate?
24 V
120 V
480 V
240 V
A DC surface pump is rated for 12 V and 41.6 A.
How much power will it use?
350 Wh
500 W
500 Wh
350 W
A 400 watt module measures 66.5” by 41.1”.
Calculate the watts per square foot.
21 W/ft²
18 W/ft²
32 W/ft²
47 W/ft²
A 330 watt module measures 1053 mm by 1590 mm.
Calculate the watts per square meter.
17.9 W/m²
197.6 W/m²
26.79 W/m²
1.79 W/m²
A 1.5 MW PV array is operating at 650 W/m².
What would be the approximate PV array power?
975 MW
97,500 W
975 kW
9.75 MW
A 750 kW PV array is operating at 1,110 W/m².
What would be the approximate PV array power?
675.7 kW
832.5 kW
832,500 kW
6.757 MW
An inverter has a maximum output current of 47.2 A.
The National Electrical Code® requires overcurrent protection
devices be sized to 125% maximum output current.
What is the minimum overcurrent protection device size for this inverter?
61 A
57 A
59 A
52 A
An inverter has a maximum output current of 2,520 A.
The National Electrical Code® requires overcurrent protection
devices be sized to 125% maximum output current.
What is the minimum overcurrent protection device size for this inverter?
2,994 A
3,150 A
3,193 A
3,056 A
