Up to 3.5 gallons per day
Bad news for Tesla's ailing solar panel business
The roof will add up to 56km of range a day
But will it make building new homes harder to afford?
An expensive product but it looks great
There are 305 gigawatts of solar generation capacity in the world, up from 50 gigawatts in 2010
Amazon plans 41MW of solar installations by the end of 2017
Return on investment drops to under 10 years, some as low as 8