After Tesla’s big (yet vague) announcement in October about manufacturing solar shingles, the non-solar media world was beside itself. “Finally!” they said. “What a great idea! This will transform the solar industry!”
But the solar industry knew better. Solar shingles are not new. Building-integrated photovoltaics (BIPV)—the generation category solar shingles fall under—have been around since the beginning. Gifted minds envisioned a product that could incorporate into a building’s structure and generate electricity. More than just integrated shingles, BIPV also includes semi-transparent solar panels used as replacement glass windows or skylights—anywhere solar cells are used as building construction materials.
And although Tesla’s solar roof does appear to look and install differently than traditional BIPV, many questions still remain. While we wait for answers on details such as price, output and longevity (CEO Elon Musk said Tesla should start volume production this coming summer), here’s a refresher on two already successfully established solar shingle manufacturers.
When solar shingle godfather Dow exited the market with its Powerhouse system in July 2016, the industry wondered if this was the end for BIPV. Not the case, said SunTegra CEO Oliver Koehler. SunTegra, formerly known as Integrated Solar Technology, produces solar shingle and solar tile roof systems with crystalline silicon technology, while Dow used expensive and less efficient CIGS thin-film.
“We base our products on standard crystalline solar cell technology, which enables us to tap into the industry’s existing economies of scale and provide a competitive cost and similar efficiencies and reliability to standard solar panels,” Koehler said in an SPW interview.
SunTegra’s Solar Shingle and Solar Tile roof systems replace roofing materials and are best installed on a new roof or remodeling project. The products attach directly to the roof deck in an overlapping pattern. A patented TegraVent design promotes ventilation, reducing heat throughout the system and increasing energy production.
SunTegra Shingle (2 x 4 ft) is rated at 100 W, while SunTegra Tile (1.5 x 4 ft) is 67 W. Both have rated efficiencies close to 15%. SunTegra systems have warranties similar to traditional racked solar systems: a 20- to 25-year power guarantee and a 10-year product guarantee.
The real advantage comes when comparing non-solar roofs and standard rack-mounted solar systems with solar shingles. Asphalt shingle roofs have a 15- to 30-year lifespan (depending on climate). Roofs often have to be replaced before a racked solar system reaches its end of life. Removing and reinstalling a racked system is a pain. A BIPV system stays in place and often exceeds a non-solar roof’s lifespan, saving the headache of a solar reattachment and the cost of a re-roofing.
SunTegra got its start in 2013, and its leadership has decades of solar experience. Its marketing efforts have taken off in recent months, and the company seems poised to establish some solar shingle market dominance.
In addition to a rack-mounted PV system, popular construction material manufacturer CertainTeed also produces its Apollo II and Apollo Tile II BIPV systems—and has for years. With more than 100 years’ experience in the roofing business, CertainTeed offers a unique level of understanding of solar roofing products and how they function as building-integrated systems.
The Apollo II products produce 60 W per shingle and are wind-resistant and water-tight. Apollo II’s all-black design and Apollo Tile II’s brown/black design allow the panels to visually blend in with certain shingled and tiled rooftops. Also made of crystalline silicon, CertainTeed’s solar shingles have comparable efficiency to other solar shingle products on the market today.
Rafters aren’t needed for successful installation. Apollo II solar shingles attach directly to the roof sheathing with standard deck screws. CertainTeed has developed comprehensive installation instructions for its systems and trains credentialed installers on proper installation techniques.
In a recent article exclusive to SPW, CertainTeed product development leader of photovoltaics Christopher Fisher explained the average savings associated with the Apollo II systems.
“Simplicity and efficiency add up to substantial savings, which can be passed along to the homeowner,” he said. “For a typical 6-kW Apollo II system, the average savings on roofing materials and labor alone when compared to separate roofing and roof-mounted PV installations is $770 to $1,210. For a typical 6-kW Apollo Tile II system, savings is usually between $1,260 and $2,520.”
CertainTeed is a bankable company; in business since 1904, owners can be assured the 25-year power generation guarantee and 15-year installation workmanship warranties will be honored.