Although there are many positives to using solar energy for homes, there are also some negative elements. The two greatest obstacles for those interested in this type of alternative energy are the cost of installation and the appearance of rooftop panels. Believe it or not, some people think that solar arrays are downright ugly! Solar roof shingles can be the perfect choice for those particular homeowners, since the tiles or shingles are flush with the roof and there are no special installation tools required--the contractors install them just as they would regular roofing shingles, substantially reducing costs. If the roof needs work and you are seriously considering solar panels, you can get two jobs done at once by installing solar roof shingles in place of a rooftop solar array.
Why Solar Power Roof Shingles?
Solar shingles are a style of thin-film, flexible solar panel produced in sheets that look very much like regular asphalt roofing shingles. This Old House Magazine took a look at these products, described as building-integrated photovoltaic (BIPV), that blend photovoltaic cells, other roofing components and asphalt, metal and even slate. They generate electricity in the same way as regular pv panels, and can be connected to the grid or utilized for off-grid locations, such as remote cabins. A single solar roof tile provides a mere 50-200 watts, but the sheer volume of solar cells and the area covered results in an energy producing powerhouse. Another advantage is that solar roof tiles do not need to be covered with glass, unlike panels, and this increases both sunlight absorption and efficacy. As you would with an installation of rooftop solar panels, the shingles should be installed on parts of the roof that are never shaded, and must be south-facing.
Solar Roof Shingles: A Less Costly Alternative to Rooftop Panels
Technological advances are constantly improving solar shingle efficiencies, and new products are arriving on the market all the time. Dow Chemical presented their new solar shingles in 2009, and announced plans to launch the product by the end of 2011. Dow notes that the overall cost of their product, called the "Powerhouse", will be less than that for conventional solar energy systems, for a couple of reasons. The first is because of a new type of semiconductor used, copper indium gallium diselenide, which is less pricey than silicon-based materials. The second is the fact that roofers do not need special training to install these shingles, which immediately reduces costs since a large portion of "going solar" are professional installation costs. Industry sources predict that, just as prices are falling each year for standard solar panels, the same will be true of solar shingles as improvements in technology and production efficiency will lower costs.
Even though installation costs are usually much lower for solar roof shingles than for a traditional rooftop solar array, certain common system components such as an inverter ( which will need to be installed by an electrician) will still be a necessary part of your new system. The real savings, for the most part, lies in the fact that the roofing installers take on the biggest part of the project, which is the actual installation of those solar panels onto your roof. Commonly, rooftop solar installations cost about 30-40 cents per kwh; solar roof shingle installation, however, costs a mere 20-25 cents per kwh.
Other Positive Aspects of Solar Roofing Shingles
Solar roof shingles have other things going for them, too. In addition to reduced costs and a more agreeable configuration, solar roof shingles are lightweight and, due to their less obtrusive appearance, are generally more welcome in housing developments with strict zoning laws concerning appearance. Most companies that manufacture these solar products offer colors that more easily blend with an existing roof, which could conceivably increase the resale value of your home more than a standard PV installation might. Warranties for these products are similar to those for other types of roofing, generally between 20 and 25 years.