Suggested issues to consider:
Supply Chain Sustainability
The solar energy system industry are facing major challenges in relation to the supply of raw material. What measures are the companies taking to ensure supply chain sustainability (environment and social)?
Post-Consumer Waste Management
Are there major challenges related to post-consumer waste management in the area of distribution? Is the company taking these challenges into account when designing and evaluating the project?
Placement of Production Site
Arable or non-arable land? Ecosystem impact?
Maybe this could be done in a similar manner as the due diligence summary provided for each company: displaying key strengts and risks