First, they said electric cars didn’t go far enough. Now, they reach hundreds of miles. Then, they said electric cars were too expensive. Soon, owners will be able to make money while they sleep.

Electric cars are starting to generate income by storing power and selling it back to the grid. Over the lifetime of an electric vehicle, owners could earn enough to offset most of the purchase cost.

Electric cars are getting cheaper.

Thanks to rapidly declining prices, electric vehicles (EVs) are heading for the garages of middle-class homes. Tesla’s recently announced Model 3 comes with a $35,000 price tag. State and federal tax incentives drive down the cost even further. In California, the total comes to $25,000 after tax breaks, roughly the sticker price of a new Toyota Camry. That doesn’t take into account fuel savings.


To get an idea of how existing electric cars stack up against gas-powered vehicles, check out the Department of Energy’s Vehicle Cost Calculator. The numbers vary from car to car and depend on factors like the price of gas, the price of electricity and the fuel economy of vehicles being compared. At the improbably high end, Elon Musk says Tesla owners stand to save $10,000 on fuel over five years. Soon, owners will see additional benefits from selling stored power back to the grid.

Power grids need energy storage. With renewables, they are going to need a lot more.

Grid operators respond to peaks in consumer demand by ramping up additional gas or coal-fired power plants. This is dirty, expensive and generally a blunt tool tracking the hills a valleys of energy use. It more efficient to buy back electricity stored in EVs and homes batteries — what energy nerds call “distributed storage.”

Distributed storage is essential for integrating renewable energy into the grid. How do utilities meet consumer demand when the sun stops shining and the wind stops blowing? One tactic is to time-shift power use, running energy-intensive appliances when renewable output is at its highest. Another tactic is to store surplus power until it is needed.