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.
The good news for Tesla is that, by all accounts, battery prices are dropping fast. In 10 years we should be at or near $150 per kWh, at which point a 30 kWh or even 60 kWh plus Tesla's solar tiles should be a competitive purchase for any home, in need of a new roof or not.