Systems S.D. May 10-24 3-11-10 Midterm Presentation Dan Congreve - - PowerPoint PPT Presentation

Solar Cells for Total Energy Systems

Dan Congreve Jay Eggenberger Kang Kang Madeline Oglesby Kyle Veugeler Faculty Advisor: Dr. Vikram Dalal

S.D. May 10-24 3-11-10 Midterm Presentation

Project Plan

• Senior design project

▫ Fabricate and test performance of amorphous and nanocrystalline tandem junction solar cells for total energy systems

• Solar total energy system

▫ Provide both hot water and electricity from the same panel ▫ The tandem junction design will have increased efficiency at high temperatures (70-80 C)

• Deliverables

▫ Fabricated solar cells that meet requirements ▫ Test results that confirm our theory

Project Design

• Anti-Reflective Coating

▫ Layer of transparent conductive oxide serving as the top contact ▫ Minimize absorption and reflection losses for incident light of wavelengths 400-1100 nm ▫ Provide good electrical contact while letting most of the incident light pass through solar cell layers

• a-Si and nc-Si Thickness

▫ Spectrum Splitting ▫ Current Matching

Semester Progress

• Received training on I-V testing
• Performing tests to confirm thesis

▫ Show that nc-Si and a-Si perform better than c-Si at high temperatures.

• Devices fabricated and tested week of 2/15/10

IV Test Procedures

• Lab station calibrated with test cell
• Lamp provides illumination of 1 sun
• Placed sample solar cell under lamp
• Swept open circuit voltage from -0.5 to 1 volt

above Voc

• Observed Fill Factor, current, and power output
• f the solar cell
• Repeated test results at (25, 50, 75, and 100

Celsius)

• Plotted results vs. temperature

I-V Curves vs. T: a-Si (2-12843)

0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Current (mA) Voltage (V)

I-V Curves for Various Temperatures for a-Si Solar Cell

25 C 50 C 75 C 100 C

I-V Curves vs. T: nc-Si (1-6947)

0.5 1 1.5 2 2.5 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 Current (mA) Voltage (V)

I-V Curves for Various Temperatures for nc-Si Solar Cell

25 C 50 C 75 C 100 C

I-V Curves vs. T: a-Si (2-12921)

0.1 0.2 0.3 0.4 0.5 0.6 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 Current (mA) Voltage (V)

I-V Curves for 2-12921 a-Si Tandem Cell

25C 50C 75C 100C

• Begin crystalline I-V testing to establish baseline values
• Receive first wave of tandem junction cells and begin I-V testing

process

• Observe initial data results to determine design efficiency
• Begin I-V testing secondary wave of tandem solar cells
• Obtain training in Quantum Efficiency testing of cells
• Begin QE testing of all tandem junction cell designs
• Conclude, compile and analyze all data and findings
• Begin creation of senior design informational poster board

Future Plans