Solar energy isn’t always bright and sunny, apparently; there’s a dark side, too. “Solar energy is green, but it’s not all green,” said Annick Anctil, associate professor of engineering at Michigan State University. She’s working to make photovoltaic technologies greener and more sustainable.

The problems

There are a lot of different kinds of solar panels and installation methods in use. Some panels are made from materials that are in scarce supply, and some leach hazardous chemicals into the environment. 

“If you get better performance out of the solar cell, but it uses a scarce or toxic material, you haven’t necessarily made anything better,” Anctil said in a news release. “The solar cell may work better, but you’ve also created a new problem.” 

Solar panels operate differently in various conditions and climates, meaning they’re not universally beneficial in all applications.

“If you take a solar panel and install it in Michigan, then install the same kind in Arizona, they’re not going to perform the same,” Anctil said. “They won’t have the same environmental benefits.”  

Anctil explains that the cost of PV installations has decreased 70% over the past decade while capacity is increasing nearly 50% every year. In addition, the industry is experiencing bankruptcies, more manufacturing shifting from Europe to China, and evolving economic policies and incentives. Plus, solar panel recycling is not yet a widespread practice, although it is expected to increase significantly in the coming years as solar installations tick up.

“All of these factors have affected PV systems design,” Anctil said. “We already know that the average lifetime of modules has been overestimated and so has their environmental benefit.”

The research

Anctil’s research team earned a National Science Foundation CAREER Award of more than $400,000 to examine the environmental impact of solar photovoltaic technologies across the country. They are looking at the effects of technological changes, economics, and policy on PV over time. An integrative simulation model assists them with predicting the combined effects on the industry. 

The team is studying the material content, toxicity, and recyclability both for current and future PV technologies. For example, Anctil notes that PV modules’ composition and toxicity has changed over the past decade and that decreasing module value over time is contributing to higher solar panel recycling costs.

What’s next

In addition to providing insight on solar technology sustainability, Anctil would like to create an educational simulation tool to help train engineers to work in the energy sector.