French utility Engie has joined forces with Fiat Chrysler Automobiles (FCA) to build the world’s largest vehicle-to-grid (V2G) project — using electric-vehicle (EV) batteries to provide up to 25MW of stored renewable energy to help balance the Italian electricity network.

The idea behind V2G is that EVs will be charged when renewable energy on the grid is plentiful and cheap, and some of that electricity will be sent back to the network when the supply of wind and solar power is low and the cost of energy is high.

As FCA explains: “The need for ‘balancing resources’ in the power grid is expected to increase considerably in the future: on the one hand to support the development of renewable sources, where energy production is by default nonprogrammable; on the other hand, to manage the deployment of electric vehicles, which — given that they require power to be recharged — could further destabilise the system.”

Work on the first 50kW phase has already begun at the car maker’s Drosso logistics centre at its Mirafiori plant in Turin, northwest Italy, with 450 metres of trenches excavated to host the cables for 64 two-way fast-charging points for 64 EVs — and is scheduled to be completed in July.

V2G infrastructure for 700 EVs is expected to be installed by the end of 2021 at the project, which is a collaboration with local transmission system operator Terna.

“In its final configuration, the project will be capable of supplying up to 25MW of regulatory capacity, making it the largest V2G facility ever built in the world,” said FCA in a statement. “In addition, by aggregating with other FCA “assets” at Mirafiori — including 5MW of solar panel capacity — this V2G infrastructure will become a true Virtual Power Plant, indeed the most innovative one in Italy.”

"The project is acting as our laboratory to experiment on and develop an offering to add value in the energy markets,” said Roberto Di Stefano, head of EMEA e-Mobility at FCA. “On average, cars remain unused for 80-90% of the day. During this long period, if connected to the grid by Vehicle-to-Grid technology, customers can therefore receive money or free energy in exchange for the balancing service offered, without compromising their mobility needs in any way.”

Engie CEO Carlalberto Guglielminotti added: “Estimates have it that by 2025, the total storage capacity of electric vehicles in Europe will be over 300GWh, representing the largest distributed resource available to the European energy system. The market for V2G infrastructure, to date consisting almost exclusively of experimental projects, is now ready to get off the ground.”