the effects of harsh environments on solar cells
DESCRIPTION
THE EFFECTS OF HARSH ENVIRONMENTS ON SOLAR CELLS. Laura Bruce, Brian Dawes, James Horner, Krupa Patel, Ronak Patel, Nicholas Porto, Steven Scarfone , Olivia Shabash, Priyanka Shah, Daphne Sun, Jisoo Yoon Advisor: Dr. Paul V. Quinn Sr. Teaching Assistant: Sally J. Warner. - PowerPoint PPT PresentationTRANSCRIPT
THE EFFECTS OF HARSH ENVIRONMENTS
ON SOLAR CELLSLaura Bruce, Brian Dawes, James Horner, Krupa Patel, Ronak Patel,
Nicholas Porto, Steven Scarfone, Olivia Shabash, Priyanka Shah, Daphne Sun, Jisoo
Yoon
Advisor: Dr. Paul V. Quinn Sr.Teaching Assistant: Sally J. Warner
NASA Strives for Efficient Solar Cells
NASA interested in decay of cells
Solar Cells in Space
Variables tested include: Light intensity Wavelength Environmental factors such as radiation, heat, and freezing
Conditions in Space Average temp:
2.725 Kelvin (-455˚F)
Sunlight temp: 393 Kelvin (248˚F)
Radiation affects cells
The Photoelectric Effect Generates current
Increasing light
frequency increases electron energy
Increasing electron energy increases current
h = Planck’s constantf = frequency Eph = photon energyK = electron energyφ = work function
Doping Silicon Primary material
Diamond FCC crystalline structure
Doped with boron and
phosphorous atoms
Doping Silicon
N-Type P-Type
How Solar Cells Work
Apparatus
BaselineSix light bulbs used to create baseline:
65 Watts
Comparing Wavelengths of Light
0
0.5
1
1.5
2
2.5
3
3.5
0 0.2 0.4 0.6 0.8 1
Volta
ge (m
V)
Percent Intensity
Voltage vs. Intensity
Blue Bulb 50 W
White Bulb 25 W
Clear Bulb 75 W
Yellow Bulb 25 W
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
0 1 2 3 4
Curr
ent (
mA)
Voltage (mV)
IV Curve
Blue Bulb 50 W
White Bulb 25 W
Clear Bulb 75 W
Yellow Bulb 25 W
Comparing Different Intensities
00.5
11.5
22.5
33.5
44.5
0 0.2 0.4 0.6 0.8 1
Volta
ge (m
V)
Percent Intensity
Voltage vs. Intensity
Blue Bulb 50 W
Blue Bulb 65 W
Blue Bulb 150 W
0
0.5
1
1.5
2
2.5
0 1 2 3 4 5
Curr
ent (
mA)
Voltage (mV)
IV Curve
Blue Bulb 50 W
Blue Bulb 65 W
Blue Bulb 150 W
Liquid nitrogen exists at
77.2 Kelvin (-320.7°F)
Freezing Solar Cells
Effects of Freezing
0
1
2
3
4
5
6
7
8
9
0 0.2 0.4 0.6 0.8 1
Volta
ge (m
V)
Percent Intensity
Voltage vs. Intensity (Cell A)
Baseline
1st freezing
2nd freezing
3rd freezing
4th freezing
Effects of Freezing
0
1
2
3
4
5
6
7
0 0.2 0.4 0.6 0.8 1
Volta
ge (m
V)
Percent Intensity
Voltage vs. Intensity (Cell B)
Baseline
1st Freezing
2nd Freezing
3rd Freezing
Heating Solar Cells
Avg. temp. of object in sunlight: 248°F Highest temp. metals reach in space: 500°F
Effects of Heating
Testing Radiation 100 microcurie strontium-90 placed on
solar cell Cells exposed to beta decay (electrons)
Effects of Radiation
0
2
4
6
8
10
12
0 0.2 0.4 0.6 0.8 1
Volta
ge (m
V)
Percent Intensity
Voltage vs. Intensity
Baseline Blue Bulb 150 WAfter Radiation
0
1
2
3
4
5
6
7
8
0 2 4 6 8 10 12
Curr
ent (
mA)
Voltage (mV)
IV Curve
Baseline Blue Bulb 150 WAfter Radiation
Normal solar cell
SEM Imaging
Frozen solar cell
Heated solar cell
SEM Imaging
Normal solar cell
Factors that Affect Outcome
Resistance of voltmeters
Extraneous light sources
Overheating Other damage
Conclusion Blue Light optimum source 150 W optimum intensity Heating destroys cells Freezing may improve
performance Radiation alters cell
performance Framework for future
experimentation
AcknowledgmentsAdvisors Dr. Paul Quinn Sally WarnerLiquid Nitrogen Supplier Dr. Ryan Z. Hinrichs
Directors Dr. Miyamoto Dr. Surace
AcknowledgmentsThank you to all of our sponsors! John and Laura OverdeckThe Ena Zucchi Trust Johnson and Johnson Jewish Communal Fund Bristol-Myers Squibb Bayer HealthCare The Crimmins Family Charitable Foundation Novartis The Edward W. and Stella C. Van Houten Memorial Fund Roche Independent College Fund of New Jersey Corporate Matching Gifts: Alliance Bernstein, AT&T Foundation,
Direct Edge, Goldman, Sachs, and Company, Met Life, Microsoft Corporation, Network for Good
NJGSS Alumnae and Parents 1984 - 2009
Questions?