I have spent half of the day talking to U.S-based mounting system companies at Intersolar in San Francisco. Yes, it’s not a sexy topic. How hard can it be to engineer a pile of aluminum or steel with bolts and hooks and other stuff to prop up solar panels? It turns out that designing a good and cost effective rack isn’t so easy. The rack has to last for a few decades at least and be built in a way that makes the solar array wind resistant (and able to bear the weight of the snow, in some cases).
Here are some of the factors to consider:
- Dimensions of the solar panels.
- Framed v. frameless panels.
- Location of the installation: slanted roof, flat roof or on the ground.
- Tilting: how easy is it to adjust the tilt of the solar panels.
- The height between the ground and the solar panels.
- Types of materials: mostly aluminum versus steel.
- Ease of installation: how many moving parts are in the setup and how quickly can they be assembled and fitted with solar panels.
I talked to SunLink, Unirac, Panel Claw, Copper B-Line, IronRidge, Unistrut Energy Solutions. I have a lot of homework to do to learn more about their designs and product deployment. A few companies have shared some cost figures, which I will not mention them here for now. I want to get more numbers and do some fact checking in order to have a better discussion on costs in a story that I’ll write for PV Magazine (you can pick up a copy of the monthly at booth 9930, Level 3, at the conference). Installation can account for as much a 50 percent of the labor and material costs of a project.
Some of the companies, such as SunLink and PanelClaw, launched designs for ground-mounted projects only last year to target the utility market (they had rooftop products before that). Many American utilities, such as the Pacific Gas and Electric Co. and Southern California Edison, have signed large contracts to buy solar electricity from project developers/owners. In fact, more than half of the states require their utilities to sell renewable energy, though the electricity also could come from wind farms, geothermal fields, biomass power plants or other sources.