EFFECT OF WAVELENGTHS ON SOLAR PANEL EFFICIENCY

L U C A S T U F A N O

GLOBAL CLIMATE CHANGE• Climate Change• Extreme weather• Natural disasters

• Caused by Carbon Pollution• Burning fossil fuels• Greenhouse gasses

• Light from the Sun (Visible Light) Transformed to Infrared Light• Infrared light excites carbon in atmosphere • Creates more energy• Leaves atmosphere slower

Figure 2: Image from National Oceanic and Atmospheric Administration predicting the average change in temperature in years to come.

Figure 1: Shows some examples of the effects of global climate change.

STEPS TO SOLVING GLOBAL WARMING

•Reducing Dependence on Fossil Fuels• Green energy or reusable energy• Clean electricity• Solar panels• Growing industry, solar farms (figure 3)

• Wind power

Figure 3: Solar farms are becoming more common to see, especially on farmland.

SOLAR PANELS

• Problem: Solar panels are expensive…How can the cost be decreased?• Solar panels have room for improvement• Standard silicon solar panel loses energy to heat• Study done at California Inst. Of Tech. found the standard solar

panel converts only 15 to 20 percent of the potential energy from the sun• The efficiency of a solar panel was tested by measuring the amount of light energy being put into the solar panel, and measuring the amount of the energy that was produced by the solar panel• Plank’s constant = 6.62606957 x 10^-34 m^2 kg/s used in E=hv

• Perhaps transmitting certain wavelengths will increase efficiencies•Different frequencies, different energy levels

SUMMARY OF PROJECT

•White light causes inefficiencies on solar panels, inhibiting the amount of electricity that the solar panel can produce.

• Transmitting wavelengths onto the solar panel may increase the efficiency of the solar panel.

• The solar panel in the experiment will be charging capacitors, and when the capacitors charge completely they will discharge the energy into a LED light to test the efficiency of the wavelengths.

• Since each filter will start with the same amount of energy being put in, the time it takes to charge the capacitors will correlate to how much energy the solar panel produces under the different conditions.

• Time will be determined based off of how quickly the capacitors are charged, which can be measured by timing how long it takes for the LED light to turn on.

HOW SOLAR PANELS WORK

• Standard Solar Panel is the Silicon Photovoltaic Panel• Instantly convert light into energy• Made up of layers• One layer, the “p-type” has a element with a base to the left of

silicon • The other layer, “n-type” has a element with a base to the

right of silicon• When light energy hits the solar panel at the right frequency a

valance electron from the n-type element is freed and travels up to the p-type layer

Figure 4: The periodic table of elements focusing on the column with silicon and the columns on either side.

Figure 5: A diagram of ntype and ptype semiconductors.

Antimony Boron

HOW DICHROIC FILTERS WORK

• Photons have different frequencies, determining wavelengths

• When the photons hit a solar panel all of the different wavelengths are hitting the panel

• If there is a filter in between the source of the photons and the solar panels some frequencies may be absorbed by the filter• Depending on the filter used, a set frequency will passed through

the filter, while the other frequencies are absorbed as energy in the filter

• This is how only certain wavelengths will be passed onto the solar panel

Figure 6: The dichroic filter being put up to white light. The light transmitted by them can be seen in the pictures.

HYPOTHESIS•A silicon solar panel will produce different amounts of efficiencies when different wavelengths are transmitted onto the solar panel.

• Individual wavelengths will be more effective than pure white light.

•By using dichroic filters to extract pre-determined wavelengths such as 450nm, 550nm, and 650nm (Blue, Green, and Red) the solar panel will yield different currents, being more or less efficient when compared to white light.

• The efficiency of the solar panel will be measured by timing how long it takes the solar panel to charge capacitors in parallel. •A two sample T-Test will be used to determine if an individual wavelength is more efficient than white light. • If the p-value is more than 5%, then the wavelength is not more efficient than white light

MATERIALSSolarland Solar Panel Model Number SLP030-12 Dimensions: 545mm x 514mm x 30mm

(21.46in x 20.24in x 1.18in)

Dichroic Filters Lee Filters: R99-LD-MR16, G28-LD-MR16,

V28-LD-MR16

Cardboard

GE Reveal 60-Watt A19 General Purpose Incandescent Light Bulb (6-Pack)

1 Clamp Lamp

2 Breadboards

10 330uF capacitors

Conductive wire

LED light

Counter IC Decade/Divider

1Amp Bipolar Transistors

Common Cathode 7 Segment Displays

330 Ohm Resistors

1KOhm Resistor

200KOhm Resistor

10KOhm Resistor

4.7KOhm Resistor

220 Ohm Resistor

180 Ohm Resistor

100 mAmp Bipolar Transistor

1Amp Bipolar Transistors

2-4 Rotary Switch

22KOhm Pentiometer

Pushbutton Switch

10 Volts 3.3 uF Capacitor

50 Volts Capacitor

Pushbutton Switch

METHODS (EXPERIMENT)• Construct a circuit of ten capacitors in parallel with an LED light at the end on breadboard.

• Construct a start stop circuit.

• Construct a cardboard shell that will cover the solar panel so that no light will hit the panel.• Dimensions: (540mm in length x 30mm tall x 615mm hypotenuse) x 515mm• On the vertical side of the panel cut a hole at the center the size of the dichroic filter so that the filter will fit

tightly. • Filter is 1.965” (Diameter)

• Center of vertical side is at 15 cm from the side and 23 cm from the bottom• Place a dichroic filter into the hole previously cut out.

• Place the solar panel on a flat surface.

• Place the cardboard shell with the filter inside over the solar panel and make sure no light is shining onto the panel from the edges.

• Connect the wires from the solar panel to the start stop circuit so the circuit is using the solar panel as a power source.

• Connect the start stop circuit to the circuit of capacitors.

• Place the clamp lamp so that the light is shining directly into the dichroic filter.

• Illuminate the solar panel with the light passing through the filter.

• To begin capacitor charge time, press the push button switch down.

• After pressing down the push button switch immediately begin timing with a stopwatch.

• Record the time it took for the LED light to turn on in seconds.

• Repeat ten times for each filter, and fifteen times using no filter.

METHODS (DATA ANALYSIS)

• Find the average of each set of data

• Find the standard deviation of each set of data

• Subtract the average of one experimental set of data from the average of the control set

•Divide the difference by the square root of the quantity of the standard deviation of the control group squared divided by the amount of trials plus the standard deviation of the test group squared divided by the amount of trials

• This value is the t value

•Compare the calculated t value with the degrees of freedom (28) to the critical value from the t distribution table at the chosen confidence level and decide whether to accept or reject the null hypothesis

PROJECT

•Constructing a shell to eliminate outside light• Eliminates some experimental error

Figure 8, 9, 10: The cardboard shell constructed. Dimensions: 545mm x 514mm x 30mm (21.46in x 20.24in x 1.18in)

Figure 7: The solar panel used in the project.

PROJECT

• Extracting Wavelengths• Dichroic Filters• V28: 300-400 nanometers• G28: 450-550 nm• R99: 600-700 nm

• Collect Data Using Different Filters• Compare results to determine most effective wavelengths

Figures 12,13, and 14 show the percentage of different wavelengths that each filter displays.

Figure 11: This image was taken from the inside of the cardboard shell with the light shining through the R99, red, filter.

PROJECT

• First circuit built was capacitors in parallel• 10 330 uF

• Not effective due to measurement error when using the stopwatch

• Used this circuit for preliminary data

Figure 16: Original circuit built using 10 330uF capacitors in parallel.

Figure 15: The solar panel connected to the circuit.

Figure 17: A screenshot of the stopwatch used when timing how long it takes until the LED light turns on.

PRELIMINARY DATA

12.60 

11.43 11.21 11.34 11.56 10.99 11.76 11.88 11.63 11.39

31.41 30.90 30.86 30.33 30.68 31.21 31.36 30.64 30.28 30.73

18.83 17.86 17.99 17.78 17.64 18.05 17.64 17.71 17.54 17.71

24.53 24.16 23.54 24.08 23.59 23.76 23.93 24.73 24.41 23.68

Trials (time in seconds)

V2

8

R9

9

G

28

N

o

Filt

er

Averages

No Filter: 11.58 seconds

 G28: 30.84 seconds

 R99: 17.88 seconds

 V28: 24.04 seconds

PROJECT

• Build a Start Stop Circuit that Directs Power to Capacitors• Solar panel is origin of power•When start stop circuit is turned on power goes to the capacitors• Capacitors turn on LED light when charged• Record time it takes for capacitors to charge

•Why is this circuit more effective?• Now it can be calculated exactly when energy begins to reach the capacitors• Flow of energy can be stopped and reset in between trials• Better data because voltage going through the circuit is decreased so time increases

Figure 19: The two breadboards with the circuits. On the right is the start stop circuit and on the left is the circuit of the capacitors in series.

Figure 18: A circuit made that did not work, continuous work finally led to a functioning circuit.

DATA

0

30

60

90

120

150

Time Until LED Light Turned On

White Light

G28 V28 R99Avera

ge T

ime in s

eco

nds

it t

ook

for

the s

ola

r panel to

ch

arg

e t

he c

apaci

tors

. Avera

ge o

f 15 t

rials

.

TWO SAMPLE T-TEST DATA• White light vs. G28 Filter (green wavelength)• T-value = -129.8• P-value = 9.918%

• White light vs. V28 Filter (blue wavelength)• T-value = -247.2• P-value = 6.940%

• White light vs. R99 Filter (red wavelength)• T-value = -94.84• P-value = 5.590%

ANALYSIS AND CONCLUSIONS

• The white light produced the shortest times• There was a significant difference between white light and all the

filters, supporting the idea that white light has the most efficient effect on the solar panel

• This contradicts the hypothesis

• Of the dichroic filters, the R99 filter produced the shortest times• Could be because the solar panel is set to absorb red wavelengths

more efficiently. • Red wavelength is the lowest frequency, entering the cell with the

lowest energy so less heat is created

• A silicon solar panel will produce different amounts of efficiencies when different wavelengths are transmitted onto the solar panel.

• Individual wavelengths will be more effective than pure white light.

• By using dichroic filters to extract pre-determined wavelengths such as 450nm, 550nm, and 650nm (Blue, Green, and Red) the solar panel will yield different currents, being more or less efficient when compared to white light.

• The efficiency of the solar panel will be measured by timing how long it takes the solar panel to charge capacitors in parallel.

• A two sample T-Test will be used to determine if an individual wavelength is more efficient than white light. • If the p-value is more than 5%, then the wavelength is not more efficient than white light

WHY DIDN’T IT WORK?

•Data does not support my hypothesis • White Light produced the most efficient results• Makes sense because all the energy ends up reaching the panel

• Further Research?• Continuing off the idea that the different wavelengths cause the

inefficiencies• Would it be possible to break up each wavelength?

WORKS REFERENCED

• “Full Spectrum Boosts Solar Cell Power.” Futurity. Web. N.d. California Institute od Technology. Winter 2013. http://www.futurity.org/full-spectrum-boosts-solar-cell-power/

• “Lee Filters: Architecture and Dichroic Filters.” Futurity. N.d. n.a. Fall 2013. http://www.leefilters.com/architecture/arch-dl.html#arch-dl-dichro

• “Solarland.” Solarland Solar Panels. Web. N.d. n.a. Fall 2013. http://www.solarland.com/product.html

• “To Trap a Rainbow: Slow Down Light.” Futurity. Web. N.d. University at Buffalo. Winter 2013. http://www.futurity.org/to-trap-a-rainbow-slow-down-light/