Can Electric Cars Save The Grid? CA Might Require EVs to Have V2G by 2027

A bill has been introduced in California which would require all EVs to have bidirectional charging capability starting in model year 2027.

The bill is numbered SB 233, introduced in the California Senate by Senator Nancy Skinner, who represents the Oakland area, just north of Tesla’s factory in Fremont; it has a lot of organizations supporting it.

It would require all new electric vehicles to be “bidirectional capable” by model year 2027.

The bill doesn’t specifically define “bidirectional-capable” and directs the California Energy Commission to convene a work group and produce a report on the bidirectional capabilities of various vehicles. This would likely include vehicle-to-grid capability, which means that the car’s battery can feed energy into the electrical grid (or a microgrid), much the same way that a home solar system does when it produces more than a home can consume.

There are other types of bidirectional usage available for EVs, notably vehicle-to-load and vehicle-to-home. V2L is the most limited type and typically has lower peak draw capability – for example, the 1.8kW capability on the Kia Niro EV. V2H allows homeowners to power their home with a car’s battery, much like a Tesla Powerwall might work or like Ford’s “Intelligent Backup Power” system.

Another Umbrella Term for all of this is “Vehicle-To-Everything,” or V2X.

The bill is meant to help California’s grid tackle challenges with peak loads. As climate change makes temperatures hotter, California’s grid is often overtaxed on the hottest summer days, which are becoming more numerous. Even worse, natural gas peaker plants are the highest-polluting form of electricity California consumes, and these need to be used at peak times in order to deal with high demand.

Electric cars can be a solution to this problem since they could function as a distributed backup system for the grid. With incentives to charge overnight (utilities give cheaper rates for night charging) and additional incentives to discharge a battery when demand is high, EV owners could help the grid, the air, and potentially their pocketbooks by buying electricity when it is cheap and putting it back onto the grid when it’s expensive.

California has already moved to incentivize grid-connected storage with its recent changes to its solar net metering program. In a change that was controversial for many rooftop solar advocates, the new 3.0 net metering provision gave higher incentives to stationary battery storage and fewer incentives to normal non battery rooftop solar installations.

But there aren’t a lot of V2G-capable cars out there. Currently, only one EV on the market is fully V2G capable and has an available charger to unlock that capability for fleets. That car is also the oldest EV on the market – the Nissan Leaf, which was introduced in 2011 and has been equipped with bidirectional charging capability since 2013. But it only finally got its charger last September, several years after introduction and four years after Nissan partnered with Fermata Energy to deliver this charger.

Other vehicles have V2L or V2H capabilities (or have been promised to eventually have V2G capabilities), but only one is fully V2G capable in the US now. The bill has already been through two committees (Transportation and Energy, Utilities and Communications), during which it has been watered down significantly. Earlier versions of the bill would have also applied to all electric vehicle supply equipment (chargers), had specific incentives for bidirectional-capable EVs, and may have required these vehicles to use interoperable standards, but these aspects have all been removed as the bill has been amended.

Next, it must go through the Appropriations committee, then pass through the state Senate and Assembly, and get signed by the governor – so there’s a lot more to go, with the potential that anything could be changed by more amendments. Then many specifics of implementation would be left up to the California Air Resources Board, California Energy Commission, and California Public Utilities Commission, and the work group convened to study this issue. This includes potentially exempting certain vehicles from the requirements if they are found not to have a “likely beneficial bidirectional-capable use case.”

V2G hasn’t really taken off with consumers, not solely because there aren’t many vehicles available that allow it but also because it’s not all that easy to use. You can’t just plug your car into an outlet and use it – you need to have a grid interconnect, a system which manages the charging and discharging of your vehicle, and so on. So far, V2G has been more of a curiosity or potentially something for fleets which have large amounts of dispatchable power, but not really something that consumers can take advantage of.

A system like Tesla’s Virtual Power Plant, which connects Powerwall owners together into a large, automatically-dispatchable reserve of power for the grid (all while making those Powerwall owners money), would make it easier for consumers to use their cars in this way. And having the force of law behind it, requiring all vehicles to be capable of this, could just be the kick-start needed to make these widespread. V2G benefits from a network effect, where it becomes more useful the more people participate.

There’s no real point to a single person discharging their car into the grid, but when millions of cars are involved, you could work to flatten out the famous “duck curve,” which describes the imbalance between electricity supply and demand. We hear a lot about “intermittency” as the problem with wind and solar, and grid storage as the solution to that, so being able to immediately switch on gigawatt-hours’ worth of installed storage capacity would certainly help to solve that problem.

And that could be worth a tremendous amount of money to the grid. Not only does it eliminate peaked plant usage, which is costly both economically and environmentally, but it also saves money on grid storage installation and helps to avoid costly and even deadly widespread power outages. These benefits could be thought to balance out any cost of additional incentives for V2G-capable cars. But many of those benefits are gained simply by charging the car at the right time, which helps to balance out peaks and troughs on its own.