Ursinus College
Solar Panel Orientation
Standards
3.1.10 A, 3.2.10 C, 3.2.10 D, 3.4.10 B, 3.8.10 C,
4.2.10 A, 4.2.10 B, 4.2.10 C, 4.8.12 B
Background
Solar cells are examples of useful electrical technology as they can transform the
sustainable energy of sunlight into electricity. A solar cell contains layers of two types of
silicon. Photons of light striking its surface knock electrons loose from one layer. The
electrons are drawn to the other layer. If the two layers are connected through an external
circuit, electric current will flow through that circuit. As more light is supplied to the solar
cell, more current is generated. This flow of current may be thought of as similar to a waterfall
and has two values that are easily measured. One measurement is like the height of the
waterfall, which is a fixed value. This is the electric potential and is measured in volts. The
other measurement is like the amount of water that falls down the waterfall, and allows us to
actually do work with the water. This is called the current and is measured in amperes (or
simply amps). Thousandths of an ampere are called milliamperes, or mA.
Guiding Questions
What are some positives and negatives to using solar energy?
What are some factors to be considered regarding the placement of solar panels on a home?
Materials
Solar panel from the Fuel Cell Model Car Kit
Load box from the Fuel Cell Model Car Kit
Two patch cords, red and black
Incandescent lamp
Protractor or protractor template
Safety
Wear safety goggles
Keep minimum distance of 20 cm (8 inches) between light source and solar panel
Do not concentrate light
Do not touch the hot surface of the solar panel or lamp
Solar Panel Orientation
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Ursinus College
Procedure
1. Turn LOAD knob to OFF. Use the patch cords to connect the solar panel to the
LOAD box CURRENT terminals – red to red and black to black.
2. Place the template on table top. Place the light at the corner facing toward the 0 mark.
Place the solar panel on the 0 line 20 cm away from the light.
3. Turn the selectable LOAD knob to SHORT CIRCUIT.
4. Press the ON / OFF button.
5. Check if a number appears in the “A” window.
6. Turn on the light.
7. Record the ammeter reading in the data table beside the 0 degree mark.
8. Using your protractor template adjust the angle of incidence of the solar panel to 10
degrees still keeping the center of the solar panel 20 cm from the light. Record the
ammeter reading.
9. Continue moving the solar panel around the template recording the ammeter reading at
each location.
10. Plot a graph of ammeter reading versus angle of incidence.
Data Table
Angle of Incidence
Ammeter Reading
in Degrees
in mA
0
10
20
30
40
50
60
70
80
90
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Ursinus College
Questions
1. How should the solar panel be oriented to the light source to produce optimum current
output?
2. What can be done to residential and commercial solar panels to optimize their current
output?
3. Why is it important to keep the center of the solar panel the exact same distance from
the light source for each different angle?
4. How could you use your graph to predict the milliamp reading for 35 or 75 degrees?
5. Approximately how many years must residential and commercial solar panels be in
use before the energy savings offsets the installation costs?
References
Revised from Heliocentris Dr FuelCellTM Model Car Laboratory Manual, Heliocentris
Energiesysteme GmbH, Rudower Chaussee 29, 12489 Berlin, Germany
Solar Panel Orientation
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Ursinus College
70°
60
50°
40C
30°
. 0°
Fig. 5-1 0 Template for solar panel orientation
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Ursinus College
Teacher Notes.
The Solar Panels are most fragile. They must not be bent!
Make sure students do not place the artificial light source any closer than the 20 cm noted
in the procedure.
Approximate time:
About 15 minutes to set up.
Can easily be done in one standard non-block class period.
Answers to Questions:
Guiding Questions
What are some positives and negatives to using solar energy?
Answers will vary.
What are some factors to be considered regarding the placement of solar panels on a
home?
Facing N, S, E or W?, Angle on roof?
Questions
1. How should the solar panel be oriented to the light source to produce optimum
current output?
The solar panel should be at zero degrees meaning the light rays shine directly on
the flat face of the panel.
2. What can be done to residential and commercial solar panels to optimize their
current output?
Orient them so they receive the most direct sunlight for the longest period of time.
Perhaps install them to swivel to stay oriented toward the sun as long as possible.
3. Why is it important to keep the center of the solar panel the exact same distance
from the light source for each different angle?
If the distance changed with the angle, there would be too many variables in the
experiment. The distance needs to be a control. This experiment tests the
relationship between orientation and current output.
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Ursinus College
4. How could you use your graph to predict the milliamp reading for 35 or 75
degrees?
Find 35 or 75 degrees on the x – axis. Find the location on the best fit line on the
graph directly above the chosen degree. From that spot, travel horizontally to the
y-axis and read the corresponding current value. You are interpolating the value
from the graph.
5. Approximately how many years must residential and commercial solar panels be
in use before the energy savings offsets the installation costs?
Approximately ten years depending on design and geographical location.
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