Your Car Battery Could One Day Be Your Home Backup Power

Perhaps you, like me, have considered investing in a home battery system — not to go “off grid” so much as to survive blackouts. Simply having solar does not give you such protection, because when the grid goes down, your solar panels do not generate electricity. That’s required by power companies, because they don’t want you pumping electricity into downed power lines as their technicians work to repair them.

Personally, I’m holding out for a future in which the energy stored in my EV batteries can be tapped to power my home during a blackout.  There’s a term for this called vehicle-to-grid, but a more accurate term would be vehicle-to-home, since it would be done in isolation from the grid.

Because I have two EVs with combined battery capacity of 170 kilowatt-hours, I have a lot of stored power available to me at any time, even if those cars are not fully charged.  For example, 100 kilowatt-hours can provide 5,000 watts of household electricity for 20 hours.

There are commercially available inverters for creating a 120-volt outlet in any car, either gas or electric, but inevitably some automaker — probably Tesla — will create an interface that allows for the electricity stored in one’s EV battery to be tapped for household use during a blackout.

Several electric trucks are going to hit the market in 2020 and beyond, and each will have 120 and possibly 240-volt outlets for field power, which is a good start. You could run an extension cord to power critical home appliances.