Late last year, Tesla announced it was entering the home solar business through its acquisition of SolarCity, energizing both the industry and homeowners looking to make the transition to clean solar power. Tesla’s solar roof allows people to enjoy the benefits of solar energy without the hassle of installing large, heavy panels or worrying about the structural integrity of their roof.
What many homeowners don’t realize, however, is that Tesla’s technology is not entirely new. It’s a variation on the solar shingle (sometimes called a solar tile), a roofing material that functions (and, in some cases, looks) exactly like any other shingle.
How do they work?
Solar shingles have three main layers. Like regular solar panels, at the heart of each shingle is a solar cell that soaks up the sun’s energy and turns it into electricity. The cell is covered with a colored louver – a kind of thin film that permits sunlight to enter the shingle but renders its solar components invisible from the street level. Tesla CEO Elon Musk has explained that the louver operates in the same way a privacy screen on a laptop does. The louver and cell are then pressed between tempered glass.
The power output of a single solar tile is relatively low, about 50 to 200 watts. But when they’re linked in sequence, they can produce as much energy as a regular solar panel.
Why choose solar shingles?
Solar shingles have several advantages over regular rack-mounted solar systems. Since they’re small and lightweight, they’re easier to install than regular solar panels. The installation process is also easier because they don’t require a roof evaluation or mounting.
Solar shingles might also come with longer warranties than standard solar panels. Tesla’s shingles, for instance, are guaranteed to produce power for 30 years, and the tiles themselves are warrantied to remain intact over the lifetime of the house. Standard solar panel warranties, on the other hand, typically last just 20 to 25 years.
Solar shingle makers also tout the aesthetic value of solar shingles. Compared to regular solar panels, which jut out visibly from the surface of the roof, solar shingles lay flush against the roof because they are the roof. Tesla’s solar roof elevates the aesthetic element of the solar shingle even further, as the tiles with and without solar cells are visually indistinguishable. (If you don’t go with Tesla – or a Tesla-like system of total roof coverage – you might instead end up with a bluish or blackish island of solar shingles surrounded by regular roof tiles unless you carefully select them to match their solar counterparts.)
And like more traditional forms of solar energy generation, solar shingles qualify buyers for generous federal and state financial incentives like rebates and tax credits.
Who makes them?
Tesla isn’t the only manufacturer of solar shingles, but the market is small. CertainTeed’s Apollo Tile II boasts energy generation capabilities of 60 watts per tile and a weight below that of even an average tile roof. Atlantis Energy Systems produced a solar shingle for several years before the company was reorganized into Aesthetic Green Power; it’s currently unclear whether AGP will continue producing solar tiles.
Before Tesla, Dow was the big name in the solar shingle industry. The multinational manufacturer began producing its solar shingle, the Powerhouse, in 2011. When the technology behind the Powerhouse debuted in 2009, Time named it one of the top 50 inventions of the year. The company suggested that their shingles would cost 10 to 15 percent less than traditional solar arrays and expected them to bring in some $10 billion by 2020.
Instead, Dow failed to find a market niche and stopped selling the Powerhouse last year. Compared to traditional solar panels, the shingles had lower efficiency rates and higher costs. Additionally, the company suffered from internal disruption, merging with DuPont in 2016.
But Dow isn’t ready to call it quits just yet. The company recently announced a partnership with RGS Energy to revive the Powerhouse. Dubbed “Powerhouse 3.0”, the new line of shingles show that Dow has learned from its mistakes. Instead of utilizing CIGS thin-film technology, the shingles will now use silicon solar cells, which should significantly reduce their cost and improve their efficiency. The shingles are already available for preorder and Dow expects to begin installations in 2018.
How much do they cost?
The price of getting your roof outfitted with solar shingles depends on the manufacturer and the number of tiles you need. The more energy you use, the more solar panels your home will require. Tesla, for instance, allows customers to cover their roofs with anywhere from 40 to 70 percent solar shingles, and covers the rest of the roof in regular tiles. (Covering more than 70 percent of the roof in solar tiles is not possible due to building regulations.)
Residential solar systems cost about 30 percent less than the average cost of Tesla’s solar roof. But analysts expect that like other areas of solar technology, the price of solar shingles will continue to decline – an outcome that is even more likely when heavyweights like Tesla and Dow are in competition. A recent BBC Research study found that the market for building-integrated photovoltaics (BIPV), of which solar shingles are one example, is expected to grow from $2.5 billion in 2016 to $4.3 billion by 2021.
Should I get solar shingles?
Since so few companies offer solar shingles, you might have trouble finding an installer in your area. Even Tesla’s solar roof is still only available in California.
Another variable to consider is the aforementioned cost. But for some homeowners, the superior appearance could well be worth it.
The best customers for solar shingles are people who are building new homes or replacing their old roofs. In these cases, installing solar shingles could be less expensive than the combined cost of installing solar panels and standard roofing tiles. To explore this in more depth, see our article that thoroughly explores the Tesla Solar Roof vs. traditional panels pricing and tradeoffs.