Tesla tsla said Wednesday that it has finished the first installations of its solar roofs, less than a week after the company’s mass-market Model 3 cars started rolling off the production line.
Announced in its second-quarter earnings report, Bloomberg reports that these early adopters of the solar roofs are all Tesla employees—just like the first Model 3 customers last week. Tesla said that this approach allows the company to smooth the sales and installation process ahead of a wider release to the public.
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“I have them on my house, [Chief Technology Officer] J.B. [Straubel] has them on his house,” CEO Elon Musk said, according to Bloomberg. “This is version one. I think this roof is going to look really knock-out as we just keep iterating.”
The tiles are made to resemble regular high-end roofing material, while sunlight can pass through them onto solar cells thereby producing energy.
First unveiled last October ahead of the automaker’s acquisition of solar power equipment maker SolarCity, Musk later said that the solar roof will cost less than conventional rooftops. Tesla has opened online orders since May, allowing prospective buyers to estimate the cost of installing a solar roof after putting down a $1,000 deposit.