Written by Solar Citizens supporter Kyle Pennell. 

Back in 2016, Tesla acquired solar panel installer and manufacturer SolarCity to help it produce a new product, the solar roof. Tesla’s solar roof is made of a series of roofing tiles, some of which have solar cells inside. To all outward appearances, the tiles are identical, and each produces only a small amount of energy on its own. But when joined together, the tiles generate energy at a level that rivals standard solar panels.

When it was announced, the solar roof seemed like a revolutionary idea: a product that offered all the benefits of clean solar energy without the need for big, bulky solar panels. But what few people realized was that Tesla’s solar roof was actually a variation on the solar shingle (sometimes called a solar tile), a technology that has has been available commercially since 2005 and was patented in the 1970s.

Solar shingles consist of three three main layers. Like regular solar panels, each shingle absorbs and transmits the sun’s energy using a solar cell. A thin film known as a louver is placed over the cell. The louver allows light to pass through and makes the solar cell and other components within the shingle invisible from the street level. Finally, the louver and the cell are sandwiched between two pieces of tempered glass.

Compared to regular rack-mounted solar systems, solar shingles offer a number of advantages. Small and lightweight, the shingles are much easier to install than regular solar panels. And since they don’t require a roofing evaluation, the whole installation process proceeds much easier.

Some solar shingles are bundled with longer-than-average warranties. Tesla’s solar roof, for instance, is guaranteed to produce power for 30 years; the standard solar panel warranty is just 25 years. On top of that, the tiles themselves are warrantied for the entire lifetime of the house.

Manufacturers also celebrate solar shingles’ aesthetic value. Standard solar panels are highly visible and jut out visibly from the roof. Solar shingles, on the other hand, are often (though not always) indistinguishable from standard tiles on any other roof.

Tesla isn’t the only company that produces solar shingles. Solarmass, for instance, offers a tile that the company claims has a carbon footprint 136 times lower than that of standard solar panels. Aesthetic Green Power, headquartered in Minnesota, offers two solar tile products and recently partnered with Columbia University and Virginia Tech to improve its production processes. And Redwood Renewables currently manufactures a solar tile that, the company claims, has an energy efficiency rate that exceeds that of standard solar panels by nearly 20 percent.

But before Tesla, Dow was the biggest name in the solar shingle industry. When the technology behind its solar shingle, the Powerhouse, was first unveiled in 2009, Time named it one of the inventions of the year. The company claimed that the Powerhouse would cost 10 to 15 percent less than traditional solar arrays and projected sales of $10 billion by 2020.

But Dow stopped selling it in 2016 after just five years in production. Compared to traditional solar panels, the shingles were both more expensive and less efficient. The final nail in the Powerhouse’s coffin was the merger between Dow and DuPont, which saw both companies reorganized into DowDuPont.

But the company, it seems, isn’t ready to throw in the towel on solar shingles just yet, and recently announced its intention to revive the Powerhouse. In partnership with RGS Energy, the new ”Powerhouse 3.0” will utilise standard silicon solar cells rather than the CIGS thin-film technology that previous iterations of the Powerhouse did. This design decision should boost the shingles’ efficiency and lower their cost. DowDuPont plans on beginning installations this year.

The cost of getting your roof outfitted with solar shingles depends on the particular tile you choose to install and the number of tiles you want. As is the case with regular solar panels, the more energy you use, the more solar shingles your home will need. Tesla’s solar roof, which became available for preorder in Australia last year, will cost about $22 per square foot. According to some estimates, that means that a standard rooftop solar setup will cost about 30 percent less than the average cost of Tesla’s solar roof.

Australia-based Bristile Roofing offers its own solar roofing product which, like Tesla’s, consists of a mixture of solar and non-solar tiles. While it costs about three times as much as a regular solar setup, Bristile’s solar roof boasts efficiency rates on par with standard solar panels.

Tractile offers a somewhat more affordable and more efficient solar roof. Priced at $13,000 for a four-kilowatt system, the Tractile Eclipse is unique in that its tiles are far larger than normal tiles, and resembles a grid of interlocking solar panels more than it does a standard solar shingle installation.

The most affordable Australian option today is from Nulok Roofing. The company’s award-winning “solar inserts” boast efficiency rates of 18 to 22 percent and can cost as little as $8,000 (excluding the cost of an inverter and installation).

But according to PowerScout, a California-based solar startup, the price of solar shingles will continue to decline along with other costs in the solar industry. That’s even more likely now that big players like DowDuPont and Tesla are in the market.

Solar shingles are an especially good idea for anyone building a new home or replacing their old roof. By combining roof replacement and solar panel installation into a single process, homeowners could save money that would otherwise be spread out over two separate upgrades. Thanks to Australia’s generous financial incentive programs, installing a solar roof is both easy and affordable. And like regular solar panels, a solar roof can help you save dramatically on your energy bill while doing your part to lower your carbon footprint.