Planet Gore

About That DeathSolar Panel on Your Roof

Is it up to code? Answer: Probably not. Scientific American:

Solar panels are supposed to be a set-and-forget technology. Mine have performed just as advertised. All the installer said I need to do is look them over a couple of times a year and rinse off any dirt buildup. The approval and installation process had its delays and gaffes, but all’s well that ends well, I figure. But lately I’ve been feeling less sanguine. Solar experts have regaled me with tales of poor workmanship they find when they do spot checks of installed systems. As improperly installed joints corrode, connections loosen, and wires fray, we may be looking forward to a wave of breakdowns in the coming years. “Not only is there a potential for an increase in system failures, but there is also a potential for a rise in unsafe and potentially lethal situations,” says Corey Asbill of New Mexico State University.

I brought up workmanship last week in the context of municipal codes, permits and inspections. Installers complain about the costly and seemingly arbitrary requirements that many cities, towns and counties impose. But the other side of the story is that local officials have the important responsibility of watching over installers. A couple of people slammed me in the comments field for letting bureaucrats off too easily and giving ammunition to solar’s detractors, but they neglected to address the reality of sloppy installations. A bad fire or lethal electrocution could zap public enthusiasm for photovoltaic power and jack up insurance premiums for all solar homeowners, even those whose installers did everything by the book.

Asbill is an electrical engineer, certified installer and member of a Department of Energy “Tiger Team” that goes around the country offering solar expertise. He tells me about a talk he gave in November 2009 to a meeting of installers and inspectors in Sonoma County, Calif. “It was a really nerve-racking talk, to be honest,” he says. His team had spent several days scrutinizing a sample of 15 nearby solar arrays and finding safety hazards in every one. “I was standing before this crowd and pointing out their mistakes,” he recalls. “I was nervous.”

In an electrician’s version of Where’s Waldo, he put up photos of incorrectly installed equipment and asked the audience to spot what’s wrong. In the photo at the top of this post, for example, the red wires should be white. As code violations go, this one is fairly minor. A skilled electrician never trusts the color-coding, but lots of DIYers are not so savvy and might be led to assume a wire is hot, or not, based on its color.

This double circuit breaker should have a warning label on it, indicating that the electricity is flowing into the service panel (from the solar array) rather than out (to an appliance or lamp). Again, a skilled electrician takes the right precautions regardless of what labels do or don’t say, but not everyone is so diligent.

Here, the installer used a nonstandard part. Asbill speculates that the installers got out to the site only to realize they didn’t bring the right part, so they scrounged around in their toolbox for a substitute. The system works, for now, but will probably wear out prematurely.

This one is more serious. The terminal at the upper right should have a ground wire in it. Grounding protects you if one of the live wires ever becomes frayed and makes contact with the metal box. Without it, someone touching the box could be electrocuted.

The rest here.


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