Depending on who you ask, renewables and electric vehicles will either destroy the grid or save it. True, the sun does not always shine and the wind does not always blow, but a gas power plant can generate electricity at any time. Critics say the supposed unreliability of renewable energy will become even more precarious as Americans abandon traditional vehicles in favor of electric ones, which will draw even more power from an already strained grid.
Luckily, this is an unrealistic scenario because of something renewable energy and electric vehicles have in common: giant batteries. Solar and wind power plants are connected to huge banks to store energy and use it as needed, solving the problem of intermittency. (Engineers are turning the Earth itself into even bigger battery.) And a growing number of corded cars are equipped with vehicle-to-grid, or V2G, technology, also known as bidirectional charging. They can produce clean energy when renewables become overwhelmed on the grid, and their owners are paid to send some back to the utility to meet rising demand, creating a vast, distributed network that could make the electrical system more reliable, not less. Research has shown that around the world less than a third of electric vehicle owners such a system will have to be chosen to meet the growing need for energy storage.
Until now, we have been utility consumers (energy flowing into homes one way), but more and more we will be active participants in the grid, directing additional battery energy the other way. The shift is starting in Maryland, where last month Baltimore Gas and Electric Company partnered with Sunrun, which supplies solar power and batteries to homes, and Ford, which makes the electric F-150 Lightning, to boost national first residential V2G pilot project.
“This is the first time we've had actual customers turn off power from their electric vehicles to the grid, and we're doing it during peak evening hours,” said Chris Rauscher, vice president of network services at Sunrun, referring to periods of greatest power demand. “So we're actually reducing the load and demand on the network — flattening the curve, flattening the peak — which helps lower costs for everyone.”
To understand how this works, think of electric cars less as vehicles and more like huge batteries on wheels. In fact, the Lightning battery is 10 times larger than a home battery, Rauscher said. “Today, on-road EV batteries in the U.S. use more energy than all stationary batteries combined,” Rauscher added. “It's a huge resource.” And it's only getting more widespread: The Natural Resources Defense Council estimates that if California V2G connects all 14 million electric vehicles expected to be available by 2035, it could provide electricity to every home in the state for three days.
However, in the early days of technology, only a few models support V2G capabilities, but their number is growing. The hardware and software are not particularly complex. A special charger charges the car's battery and then charges it from the car to power the home in the case of car-to-home systems, or sends it back to the utility grid in the case of car-to-home systems.
Utilities would have to interact with everyone involved in such a program, perhaps through an app that allows a customer to, say, ask that their car never discharge below a certain percentage. Each utility will also need to figure out how much to compensate people for their electricity to incentivize them to join. the energy they transmit to the network. “We're still in the early stages,” said Divesh Gupta, director of clean energy solutions at Baltimore Gas and Electric Company. “There are a lot of things that need to be worked out, especially around customer experience.”
However, to help utilities, battery energy does not have to be fed back into the grid. For many years, owners have been using their Ford Lightning trucks to… supply electricity to your homes. These batteries are huge—the extended-range version can go over 300 miles—and they only use 5 or 6 miles of that range per hour to power a home.
Let's say the owner returns home at 6:00 p.m., when demand on the power grid is skyrocketing as everyone else stops working and turns on air conditioners and other power-hungry appliances. As consumption increases, so do electricity prices. But a Lightning owner won't have to pay for it if he uses his battery to power his home for five hours until he goes to bed, using the battery for a range of 25 to 30 miles. “Essentially, this causes the home to essentially disappear from the network,” said Ryan O'Gorman, Ford's head of vehicle-to-the-grid and vehicle-to-the-home business.
The owner can then charge again when demand and electricity prices decline. For example, if they work from home, they can charge during the day when there is a lot of solar energy flowing through the grid.
More homes using EV batteries also reduce demand on the grid, which is especially welcome during hot weather when everyone is using their AC units. From here on out, heat waves will only get worse – making it increasingly difficult for utilities to provide power that will keep people cool and safe. At the same time, more and more data centers are consuming more energy and resources. load on the mesh to the limit. This infrastructure must also take into account other forms decarbonizationlike heat pumps and induction cookers necessary for wean us off fossil fuels.
Instead of sitting idly in the garage and depreciating in value, V2G turns the electric vehicle into an asset to strengthen the grid and provide low-cost power to the home. “Cars are parked more than 22 hours a day,” O’Gorman said. “When we look at the benefits of an electric vehicle, this vehicle can now provide savings and potentially revenue streams for the customer.” (Interestingly, even trains can now send juice back on the grid and generate revenue from what they get from regenerative braking: Caltrain operates in the Bay Area. is now compensated for this energyreducing the estimated annual cost of electricity from $19.5 million to $16.5 million.)
Baltimore's residential V2G program follows other experiments around the country with larger vehicles. In Oakland, California, for example, utility Pacific Gas & Electric worked with electric bus provider Zum to introduce vehicles that take children home in the afternoon, back to the parking lot, and connect back to the network. Because their batteries are so large, they have plenty of energy left over, and this extra energy is sent to the grid just when demand spikes. They charge overnight, take the kids to school, and plug back in to charge.
This predictability could make commercial fleets even more efficient at V2G than residential vehicles, experts say. The school bus operates on a schedule that utilities can rely on: it is parked and available at certain times of the day, and makes the rounds at other times. Plus in the summer they will be available almost constantly. Other fleets, such as delivery vehicles and government vehicles, are also following regular schedules.
Fleet managers can also purchase large quantities of appropriate chargers, purchasing the system en masse, compared to a homeowner shelling out for just one. “In the short term, we believe commercial-grade V2G applications are more viable due to infrastructure costs, but we expect affordable domestic devices will become available as the market matures and demand increases,” said a spokesman for Nissan, which has long included two-way charging in its electric Leaf.
Utilities are still figuring out how to coordinate this ballet between car, charger and grid on a citywide scale. But the benefit could be large, since all of these electric vehicles represent existing infrastructure that could help reduce the need to build dedicated battery factories to store renewable energy. The less a utility has to build, the fewer costs it has to pass on to ratepayers. And with more V2G, a utility that has to import large amounts of power from a neighboring state can now store power locally.
Thus, this technology can reduce your energy bills. And for participants, their vehicles now serve as transport and energy storage. “It would seem pretty easy to imagine that this would be cheaper than just building permanent battery storage that does nothing but support the grid when needed,” said Rudy Halbright, product manager for the VGI pilot at Pacific Gas & Electric. “Because with these batteries there's no recycling. They kind of sit around most of the time.”
However, people are more complex than batteries. People with busy lives want to be able to charge their cars at any time and may not even realize how much prices fluctuate throughout the day, says David Victor, a professor at the University of California, San Diego, who studies the behavior of electric vehicle drivers. Many people enjoy the peace of mind of having a fully charged vehicle at the ready. “My assumption is that V2G will be very, very difficult for fleets outside of professionally managed fleets,” Victor said, “because we know for a fact that they will be available at the time that V2G assets are needed.”
However, given the number of electric vehicles out there, only a fraction of owners need to get involved to make a significant impact. And residential and commercial V2G can complement each other—and in turn complement larger utility-scale battery capacity—a large-scale diversification of energy storage that could accelerate the adoption of renewables. “I fundamentally believe that bidirectional electric vehicles will be something that no one has ever heard of until suddenly everyone has one,” Rauscher said. “Once we have enough clients enrolled and deployed, some percentage of clients that don't connect and don't work doesn't really matter.”
