About SolPan
SolPan (the Roof Solar Estimator) is a free web tool that helps homeowners get a first answer to "does solar make sense on my roof?" You enter an address, trace your roof from above on a satellite map, pick a panel tier, and see an estimated system size, monthly and annual output, and savings, with no account and no personal details required.
Who runs it
SolPan is operated by Franklin Polymathic LLC, a Maryland company.
Where the numbers come from
- Google supplies the geocoding, satellite maps, and, where available, detected roof planes.
- NREL, a U.S. Department of Energy laboratory, supplies the PVWatts production model and average local electricity rates.
The details are on How it works, which also lists what the estimate leaves out. SolPan gives estimates, not quotes, and isn't a substitute for a professional site assessment.
Links and compensation
If SolPan adds links to installers or other partners, they will be clearly labeled, and we will disclose any compensation we may receive for them.
Contact
Questions, corrections, or feedback: franklinpolymathic@gmail.com.