Guest Contributor Andrew Braddock, Washington State University
In 2017, 30% of all new electric generating capacity was solar power, second only to natural gas. The capacity is predicted to double over the next 5 years. Washington State University researchers are developing a photovoltaic material that could be more cost effective and efficient than current materials. Researcher Seth McPherson presented about this technology at the 2018 CleanTech Innovation Showcase in Seattle on June 25.
The material McPherson and his team are working with is Cadmium Telluride (CdTe), a stable crystalline compound formed from Cadmium and Tellurium. The material can be used to make thin film solar cells for solar panels. The thin film panels are made from one main energy producing layer made from CdTe, and surrounding layers for electricity conduction and collection. The competition, and most well-known material used in industry standard solar panels today, is single crystal silicone.
CdTe thin film panels are lighter than silicone, requiring 50 times less material. They also boast a 40% reduction in greenhouse gasses and heavy metal emissions comparatively. Thin film panels also last longer, because silicone panels break down under high heat and high humidity. The market exists for better and more efficient solar panels, so it’s the goal of the WSU Center for Material Research to further improve the technology for more effective use.
Doing so could help lower the costs of solar energy to meet goals set by the SunShot Initiative launched by the Department of Energy. The initiative aims to reduce the total costs of solar energy by 75%, making it cost competitive at large scale against other forms of energy, and without subsidies, by 2020. This cost reduction corresponds to utility-scale solar costing about $1 per watt. CdTe thin film solar panels have the potential to beat that goal by 2017.
The team at WSU recently moved towards fundamental research involving the purity of their produced CdTe. They are studying the chemistry of doping, which is where they add trace amounts of impurities to the material to get boosted electrical efficiencies. Currently, WSU is able to produce CdTe at a much faster rate than before, and dope it so that the end result is a customized high purity material, which leads to improved solar device efficiencies.
The overarching goal for the WSU Center for Material Research is to provide and develop usable materials that meet the needs of manufacturers and consumers, instead of providing material that people simply have to work around. Through this goal, they hope to contribute to the push towards sustainable energy by improving solar energy technology, making it more efficient and more affordable.