The idea of using electric car batteries to support the grid sounds like something out of a Margaret Atwood novel. Imagine millions of EVs that charge from the grid when there is excess output and release back unused juice to the grid at peak hours. Also, many believe car batteries can be used as household battery packs, collecting and storing power from renewable installations. But how realistic is this belief?

The concept of vehicle-to-grid outlined above is not new. It’s been around for about a decade, but so far, no major breakthroughs have taken place. What’s more, despite a suitable level of enthusiasm, it looks like it will be many more years until such a breakthrough takes place.

Let’s start with the technical side, assuming for simplicity’s sake that Bloomberg New Energy Finance’s estimate that by 2040, more than half of all new cars sold will be electric, so there will be sufficient battery capacity to use in the grid.

So, that’s millions of electric cars all fitted with batteries. What do utilities and drivers do if they want to play together to improve the resilience of the grid (utilities) and charge some cheap juice (the drivers)? They will need to have a communications system in place so everyone knows when the best time to charge the cars is. This problem was detailed in a December article by the Lexington Institute’s Vice President Constance Douris. It’s not even the biggest one.

There is also an issue with the discharge part of the process: some industry insiders are concerned that when the grid sucks out juice from the batteries this could lead to increased stress on the cells, potentially damaging the battery.

As serious as these problems are in their own right, they are perhaps easier to solve than the non-technical ones. If you want to use millions of cars to act as battery packs, you will need to change the way people think and this cannot be achieved with a technological breakthrough. It takes time and a lot of it, plus motivation. A case in point is Nissan’s experiment with owners of its Leaf EV, as described by Bloomberg. Related: Why Is U.S. Oil So Cheap?

Nissan offered owners of Leaf a means to adapt their car battery to power their homes. The benefit was a US$40 electricity bill every month. What happened? Over the six years since the start of the project, just 7,000 Leaf owners agreed to take part. That’s 7,000 out of 81,500 Leaf owners in Japan.

As for the right time to charge your EV so you get the lowest rates, Nissan again did a trial together with utility Tepco, this time with employees, asking 45 of them to install electricity chargers at their homes to monitor power demand on weekends. Participants were rewarded with Amazon shopping points for buying electricity when supply was highest—but it wasn’t enough to make them take advantage of the cheap juice. Only 10 percent completed the trial.

Finally, there is the simple question of money. If you want to get EV drivers on your side and convince them that it’s better for them to charge at peak production and discharge during peak demand, you—that is, the utilities—will need to make it worth their while. For now, the financial benefits of V2G are uncertain. Once this uncertainty dissipates, the chances of the concept becoming a reality would greatly improve. Just make the system easy to use and the savings from charging at the right time worth the effort. Now this is a “just” that will take years to do.

By Irina Slav for Oilprice.com

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