Can someone explain the intended function of the 7 kWhr PowerWall
Federal tax credits similar to the German model. Every time a new coal-fired electric generating plant is proposed in the US (we are the Saudi Arabia of coal, a thousand years worth is under our feet), the public votes it down (thats a separate issue).
If we can't build more coal burning electric plants, how can we power all those air-conditioners during the summer peak demand hours? Its called "time shifting"
, when the power walls charge up at night (when the coal plants are running at an idle speed), and then put electric back into the grid during 11AM-5PM peak heat hours.
Thats the first customer model, the second is "local net-metering
" where houses that agree to have solar-PV panels mounted on their roof will get a price break on the install and monthly electrical use. houses with the solar panels and Tesla walls will feed the local grid during peak demand.
Existing coal will feed the Tesla walls at night, and the sun will feed the Tesla walls as soon as the sun comes up. People who don't participate will have their electric rates go up, people who join will feel slightly less financial pain.
The Gigafactory will have no problem finding a use for cylindrical 20700 cell that it makes for the next five years. Whe Tesla finishes endurance testing of their version of solid-state batteries, the power walls will still continue to use the 20700 cell, and the cars/motorcycles/ebikes will transition to using SSBs due to the smaller size per kWh. The Gigafactory(ies) can transition to making SSBs as the demand for those grows.