Making Photovoltaic Solar Cells More Efficient

Written by Brian Westenhaus

Wednesday, 15 September 2010 13:55

The maximum use of incoming solar radiation relies on using the full spectrum of the light and infrared radiation. There’s a lot of power in the infrared – not something the current photovoltaic cell is harvesting. Photovoltaic solar cells convert energy from the sun into electricity by absorbing light. However, different materials absorb light at different wavelengths. The most efficient cells are made of multiple materials that together can capture a greater portion of the electromagnetic radiation in sunlight. The best solar cells today are still missing a material that can make use of a portion of the sun’s infrared light.  Close, but leaving a huge part of the energy unharvested.  What’s missing is the layer that converts infrared into electricity. In what could be a step toward higher efficiency solar cells, an international team including University of Michigan professors has invalidated the most commonly used model to explain the behavior of a unique class of materials called highly mismatched alloys. These mismatched alloys, which are still in the experimental stages of development, are combinations of elements that won’t naturally mix together using conventional crystal growth techniques. Read more>>