“If you have a new solar cell technology, you can see where your technology might be able to outcompete commercial silicon solar cells,” explains Tonio Buonassisi, Associate Professor of Mechanical Engineering at Massachusetts’s Institute of Technology (MIT), pertaining to the significance of their newly developed open-source tool published in the journal Joule last December 13.
“We’ve explored the convergence of two things, location and technology, to come up with a framework for predicting solar panel energy output,” Buonassisi describes of his team’s work. The research team is capable of predicting how much energy a type of solar cell can generate at any location worldwide.
The two types of solar cells – silicon and cadmium – were discovered to have a difference in energy output by at least 5%. Higher differences in output were observed in tropical regions, which have the majority of developing solar cell markets.
The GIF above depicts how the differences (represented by delta PR in percentage) between the two types of solar cells in various locations around the world vary over time.
The difference in performance between the two solar cells is attributed to shifting in solar energy depending on two factors — ambient temperature and humidity. This means that the performance of solar cell technologies is dependent on the environment they will be installed.
As an illustration of their tool’s effectivity, the research team used real weather satellite data from solar cells situated in the United States and Singapore covering one year. They analyzed where silicon and cadmium telluride solar cells will perform best.
The results showed that in hot and humid locations in Singapore, the cadmium telluride type of solar cells generated an energy up to 5 percent more than the silicon type. The same trends are projected to occur in solar cells that use higher bandgaps such as gallium arsenide or metal-halide perovskites.
Ian Marius Peters, a co-author of the study and a research associate at the MIT Photovoltaics Research Laboratory, highlights the advantages of their tool – it’s free and accurate. “Tools used by developers to predict energy yields of solar panels and plan solar systems are often expensive and inaccurate. They’re inaccurate because they were developed for temperate climates like the United States, Europe, and Japan.”
For those interested in determining where will their solar cells perform best or which type of solar cell works best in a particular location, the tool can be downloaded for free.
“The takeaway is you should decide what type of solar cell you’re using based on the type of climate in your area. There are reasons to use silicon, and there are reasons to use other technologies, like cadmium telluride. Outdoor conditions can become one of the most important factors for determining future research,” explains Peters.