Summer 2010 Intern Project- Kenechukwu Akametalu
CHARACTERIZING THE PERFORMANCE OF InGaN-BASED SOLAR CELLS VS. SOLAR FLUX
UC Santa Barbara
Mentor: Matthew Laurent
Faculty Advisor: Umesh Mishra
Department: Electrical and Computer Engineering
Due to the constant decline of fossil fuels, renewable sources of energy have gained much attention. Consequently, research into photovoltaic energy production has become an active field. With efficiencies as high as 40.7%, triple junction solar cells are currently the most efficient photovoltaic devices. The next step in increasing efficiency is to create devices with four or more junctions. Theoretically, going from four to eight junctions would increase the efficiency from 62% to 70.2%. These Multi-junction solar cells (MJSCs) would require a top junction with a band gap in the range of 2.48eV to 3.35eV. Currently, InGaN is the only direct band gap material that can meet this criterion. InGaN promises to be the missing piece in solar cell technology to achieve ultra-high efficiency. Although MJSCs are extremely efficient, due to cost they are not commercially favorable. One solution is to concentrate light onto the solar cells. It has been shown that InGaN-based devices perform better under concentrated illumination. If solar cell performance is enhanced then less material is required, thereby alleviating cost. In our research we explored how light concentration affected the performance of our InGaN devices. The ultimate goal is to use our data and better optimize InGaN-based solar cells for incorporation into MJSCs.