Just to recap from Part 1 of the series, ceramic roofing tiles are widely used all over Europe. Technological changes to date have already made this roofing material a more energy efficient and sustainable option than it was 100 years ago.
The next technological revolution for ceramic roofing tiles is the solar or photovoltaic (PV) shingle or tile). Solar shingles work like solar panels. They convert photons of light into electrical energy usingsemiconductor material. Many different types exist to fit various buildings styles and shapes (see Figure 1 below).
Figure 1: Solar tiles designed to mimic the shape and curves of traditional ceramic tile roof.
So are there benefits to using solar shingles over traditional roofing materials?
Solar (PV) Shingles/Tiles
Energy-efficiency: Solar shingles (see Figure 2) only require daylight, not sunlight, so they can generate electricity even on cloudy days. It’s also great that the roof can provide electricty to the house or building, and not just simply protect it from the weather.
Strength: They are lightweight, unbreakable, and recycable too. They can withstand the rain, wind, hail, snow. Since they simply replace roofing material, no additional support materials are needed underneath.
Figure 2: Solar shingles
Design and easy fit: Also called building-integrated photovoltaics or BIPVs, they come in several varieties, including panels that are the size of a shingle and can replace conventional shingles in a strip, semi-rigid shingles using silicon solar cells that are the size of conventional shingles, and some thin-film solar cell technologies that are very much like conventional shingles in size and flexibility. So you can imagine how easily adaptable solar shingles are to just about any house or building that already uses roofing tiles or shingles.
Good investment: One excellent benefit is that in some places you can sell unused watts back to the utility companies. So if you produce more electricity than you use, then you can, not only lower your electrical bill, but also get some money back from the utilities.
Solar shingles, being a new technology (just about 10 years in the market), have some disadvantages as well. Your roof needs to be at a certain angle with enough surface area, otherwise it will not be able to generate enough electricity. In some cases, the solar shingles can create excess heat, so you may need to provide addtional sub-roofing to protect the home or structure. So, a lot depends on your roof and your climate. It is also best to install solar shingles on a new roof since the components need to be integrated. The two biggest disadvantages are cost and lack of energy storage. Since the technology is still so new, the costs remain high. Those should come down in time as they have with regular solar (PV) panels. Since the sun is not always shining, you still need to rely on other electricity generation, at least until the cost on energy storage comes down as well.
It’s great to see that solar shingles/tiles are getting used succesfully (see Figure 3 below). I think we will see more solar shingles in the years to come as the costs go down and technological advances make them even more advantageous to use.
Figure 3: Ceramic tile roof with incorporated solar tiles.
Solar Tiles - http://www.solartiles.co.uk/index.html (accessed online on March 29, 2015)
Solar Roof Tiles UK - http://solar-roof-tiles.co.uk/ (accessed online on March 29, 2015)
Solar Shingles: What are they? - http://pureenergies.com/us/how-solar-works/solar-shingles/ (accessed online on March 29, 2015)