This is caused by the squeegee being angled incorrectly forcing the water under the rubber blade out into the dry area of the glass or from solution being pushed up into the top edge of the window.
Although there is a slight difference between our original calculation and Teslaâs new oneâlast fall we built in a cost of $6,500, Teslaâs current cost for a Powerwall as part of a Solar Roof installation is $7,000.
To compensate for the proposed added value of the âfreeâ electricity from Teslaâs roof, we added in $2,000 a year, over the lifespan of the roof. Thatâs a typical electric bill in states where solar is big, like California, Texas, and North Carolina. Tesla says the life expectancy of its tiles will be 30 years. So that adds $60,000 to the value of the roof. (Our rough estimate assumes our hypothetical Solar Roof homes generate exactly as much electricity as they use.) One final factor: the Tesla Solar Roof will work like any rooftop solar system, connecting to your homeâs electric panel through an inverter.