Principal Solar Institute

A community for development and installation professionals in the solar industry

Unbiased Ratings for the Solar Industry

The Principal Solar Institute Ratings allow easy, unbiased, comprehensive analysis and comparison of photovoltaic modules and solar power generation systems. This first-in-the-industry service is provided by the Principal Solar Institute (PSI), an organization created by Principal Solar, Inc. to advance the photovoltaic solar industry, and is not affiliated with any module or system component manufacturers. The Institute commissioned a panel of leading solar energy experts to define and certify the PSI Ratings and is making them available to the public at no charge.


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