
Recent advances in thin-film solar panel technology have given us solar shingles. These are lightweight, aesthetically pleasing mini-solar panels that look like regular shingles and that can be installed on part or all of your roof to collect solar power and turn it into electricity. Would this work for your home?
Solar power has been stalled for years with traditional crystalline silicon panels. Although they’re durable and efficient, they’re also big, heavy, and look ugly mounted on the roof of a house. Now, with energy prices soaring and increasing interest in alternative energy sources, cutting-edge solar technology has turned roof shingles themselves into solar panels. Known as building-integrated photovoltaics (BIPV), each shingle can produces between 17 and 50 watts. Solar slate tiles can produce up to 200 watts per tile. By itself, this isn’t a lot of power, but multiplied by the full square footage of your roof, solar roofing can generate enough electricity to power an entire house if you live in a sunny area with mild winters. You can then use the power either in your own household, or sell it back to your utility company in states that have net metering programs. Either way, you save money on your electric bill.
Installing the shingles is similar to the process for traditional roofing. You can choose asphalt shingles, fiber cement roofing, or slate tiles. The roofing goes down over new or previously installed sheathing. A good do-it-yourselfer can handle the physical installation job him- or herself.
After that, an electrician or specially trained roofing specialist will come out and take care of the electrical wiring so the units work together and feed into your home’s electrical system. Although some solar energy enthusiasts prefer to go off the grid entirely, most people who get these systems prefer to feed the electricity back into their local power grid. Thirty-eight states have “net metering” laws, which require electrical utilities to buy the excess power generated by home energy systems and set competitive rates. In effect, generating power at home allows you to spin your electrical meter backward. Solar garden lights are another nice touch for people who want to save energy.
A good rule of thumb for calculating solar energy needs is 1,000 watts per 1,000 square feet of living space. A 2,000 watt system with professional installation costs about $15,000. If installed on a new home, this cost can be rolled into the mortgage, which is tax deductible. The 2005 federal energy rebate program has been renewed for 2009 to give a 30 percent credit on solar shingles and other energy efficient home improvements, and for systems installed after January 1, 2009, there’s no longer a $2,000 limit on the rebate. That means the $15,000 system would in reality cost you $10,500.
Although people who live in sunny, southern areas of the United States are better candidates for solar shingle roofs than those in northern areas, the systems produce electricity as long as there’s daylight, even on cloudy days. The cost efficiency of the systems will improve as the cost of electricity increases and costs of production goes down. There are also hefty tax credits from the federal government to sweeten the deal, with more on the way from the new presidential administration. To keep track of federal and state energy programs, go to DSIRE.
I’ve never seen a solar pv roofing shingle system eliminate someone’s entire electric bill. Typically pv roofing shingles generate less watts per square foot than traditional solar panels. Also there are no roofing shingles that produce 200watts each can you please let me know the make and model number of that extremely high output roofing shingle?
@Deep Patel: I was initially put off by these numbers, too, because last time I checked, thin film was running only 15-20% efficient at capturing the sun’s energy, in contrast to traditional glass PV panels, which are about 30% efficient.
For the 50-200 watt figure, I relied on This Old House Magazine for some of my research, thinking it was credible since it ran on PBS for so many years. At the end of the article, it says, “Thanks to Noah Kaye, Solar Energy Industries, http://www.seia.org” You can also find the 200 watt claim at Calfinder.
In doing further research, I think the 50 to 200 watts per shingle claim is puffing, but that a solar slate tile like the Atlantis Sunslate could probably achieve 200 watts per tile–see the Solarserver Forum. The silicon is sandwiched between glass panels similar to a traditional PV panel–the only difference is that it’s a roofing material instead of an add-on panel. It has the same weight disadvantages as PV panels but at least it looks better.
If you still think the 50-200 watt numbers are incorrect, why don’t you contact SEIA and express the same concerns you’ve expressed here? Please feel free to return with any follow-up comments you might have after hearing their side of the story, and I’ll correct my post as necessary.
SEIA’s press contacts are here.
These shingles are really awesome! Installation is challenging, but the energy generated pays off in the long run.
@ Admin
Your numbers are not too far off, and I think we need to keep in mind that science is not perfect…
My question is, how are these shingles attached, and what do you figure — in relation to time — it takes to install them?
I would surely consider them as an option to customers in my roof replacement business.
Solar is the coming thing for home improvements. from big projects like this to stand alone lights. If you are a DIY fan and you plan on connecting it to the grid you need a qualified electrician to look at your system.
rgc