The whole key to an efficient rooftop solar power system is finding the right roof in the right spot with the least shade, and now a team of scientists has developed a new system that can provide visual images of the rooftop solar potential for any existing building. The new solar calculator, called SEES for “Solar Energy from Existing Structures,” is provided free to companies and municipalities. At least, it’s free in Sweden – the system was developed at the Department of Earth Sciences at Gothenburg University. No word yet on its availability in the U.S., so keep your fingers crossed.
Seeing Rooftop Solar Potential with SEES
The new solar calculator is based on actual GIS (geographical information systems) and climate data, which means that rather than providing estimates, it provides real information on the actual surroundings of individual roofs, and simulates how that would affect the amount of sun hitting the roof. That includes surrounding buildings, trees and other vegetation, and even nearby hills or other geographical features that could cast a shadow. SEES wraps it all up in full color graphics, and it can also break down the shadow effect into individual months or provide a yearly average. It also enables you to calculate the shadow effect on different parts of a single roof.
Google Earth Provides Free Rooftop Solar Calculator
SEES may not be available (yet) to individuals in the U.S., but if you own a building and you’re curious about its rooftop solar potential, a new Google Earth-based system can give you at least a rough idea. Unfortunately, the system is available only in California (it was developed at the University of California, San Diego), so the rest of us will have to dream on. The U.S. Forest Service does have a nifty free online user-friendly urban tree analyzer called i-Tree, which could help you scope out the tree situation.
If you know of any free DIY solar rooftop calculators, please share them with our readers in the comment thread.