Electric vehicle batteries are valuable resources that hold electricity that can be used not only to run the vehicle but give back energy to the electrical grid, reduce electric bills and power buildings or homes.
The technology to enable Vehicle-to-Grid (V2G) – also called Vehicle-to-Infrastructure (V2I) and Vehicle-to-Home (V2H) – is being tested and used with great success. It promises to help boost green energy options and disrupt the automotive and electric industries.
Analysts, insiders and providers reveal their insights.
The first step toward vehicles helping to supplement the energy grid is smart charging or V1G which can reduce CO2 emissions and charging costs.
Electricity rates are determined by many factors such as sources of energy and demand which Ryan Harty, manager of environmental business development and engineering, at Honda describes this way: “In cases where there is a high demand for electricity the most expensive and least efficient forms of power generation come on last. Therefore even just having smart charging (V1G) reduces CO2 emissions.”
V1G the precursor to V2G or smart charging uses energy from the electrical grid to charge the vehicle battery at the best time for price and renewable energy sources.
Honda is working with California Independent System Operator (ISO) Corporation that manages 80% of the California electric grid for a schedule of electricity-generating to know how to efficiently schedule charging. The data can be used not only for charging stations but also sent via telematics to vehicles, says Harty.
V2G for Saving Energy Costs
“To have V2G, you need three things, a V2G-enabled vehicle, a bi-directional charger and software to enable inter-operability between vehicle, charger and grid or building,” says David Slutzky, president and CEO Fermata Energy, a vehicle-to-grid systems company that works with energy companies and automakers.
The electricity from the vehicle can be used to offset the demand surcharge on a building. For example, a Fermata customer using a bi-directional charger saved $187.50 in fifteen minutes by drawing energy from a Nissan Leaf to avoid costly demand charges. Depending on the location, utility and charger, V2G could translate into $9,000 in savings per year for a commercial business says, Slutzky.
Fermata Energy is partnering with the Nissan Energy Share initiative, using bi‑directional EV charging technology to help power two buildings in Franklin, Tennessee, and San Diego, California. The buildings draw on the LEAF’s “lower-cost energy” to provide power to the buildings during more expensive high-demand periods.
V2G for Fleets and School Buses
Another option is for the energy from the batteries to be sent back to the electrical grid to be used by electric companies. V2G technology firm, Nuvve is supplying V2G software and hardware for fleet operators in Denmark. The vehicles are driven daily and they are plugged into V2G bi-directional chargers at night. The vehicles are generating €1860 per year per vehicle, says Marc Trahand, executive vice president of marketing for Nuvve.
“V2G makes sense for EV fleets because most are parked at night when the batteries can be used. We find that the drivers have no knowledge of Vehicle-to-Grid technology when they’re driving the vehicles. All they know is that they are driving. The only thing the driver has to do is remember to plug in the vehicle into the charger,” says Trahand who notes that Nuvve allows fleets to monitor charging and provides mobile apps for drivers.
An excellent use case for Vehicle-to-Grid is electric school bus fleets because they have downtimes in the middle of the day and also have large batteries, says Kevin Mak, principal analyst, Strategy Analytics. Day time storage is important for storing solar power which is not generated at night. In fact, Nuvve has a pilot program in operation for school buses in the city of Torrance, California, says Trahand.
Bi-directional V2G chargers in the future may also be installed onboard vehicles. Nuvve is currently working using bi-directional inverters in Honda vehicles. The only vehicles on the market now that enable V2G are Nissan, Mitsubishi and PSA Groupe vehicles that have CHAdeMo plugs and require an additional device for power conversion in charging stations.
V2G could also help in developing countries.
“We have lots of interest from the UK, France and Denmark as well as emerging countries. For example in Africa, V2G can help support small grid infrastructure,” says Trahand who confirmed that using a vehicle for V2G applications doesn’t affect the warranties of batteries. A joint venture between EDF Energy and Nuvve – called DREEV – will deploy 4,000 V2G chargers in Belgium, France, Italy, and the United Kingdom.
Vehicle-to-Home (V2H) became very popular in Japan in 2011 following the Japan earthquake, tsunami and nuclear crisis, says Mak. In Japan, customers are buying vehicle-to-home devices because a 30-kilowatt battery could power a house for three days in case of an emergency adds Trahand.
V2G Potential & Policies
“Vehicle-to-grid has the potential to offset the cost of ownership of electrical vehicles selling power back to the grid,” says Mak who predicts that V2G for fleets will deploy more quickly than for individual private EV owners. He says for V2G to work, automakers and power companies need to partner to be able to do the process seamlessly.
The state of California and Honda are working on creating the right conditions for V2G.
“The state of California is instrumental in helping utilities through its Vehicle-Grid Integration (VGI) Roadmap. Everybody is working together. We are working towards technical standards, policies and business models to introduce Vehicle-to-Grid to market,” says Harty.
V2G offers great future potential. “V2G will disrupt the automotive industry because V2G vehicles will make money while they are parked,” predicts Slutzky.
He believes that V2G will also provide large-scale energy storage to make the transition to renewable energy happen more quickly.