In London, a large-scale experiment is underway at a new bus garage, which is set to become the world's largest vehicle-to-grid (V2G) site. The project aims to feed energy stored in the batteries of an extensive fleet of electric buses back into the power network to compensate for peaks and troughs in demand.
Christened Bus2Grid, the project is led by SSE Enterprise, a company specialized in energy-sharing solutions with support from the British government and the service provider Transport for London. Between now and 2023, the experiment will be scaled up to include 100 electric buses.
Two-way charging or V2G systems work by using energy in the batteries of electric vehicles (buses, automobiles and even scooters) that are plugged into dedicated stations to provide power to nearby homes or the local electricity distribution network. Wired in this way, the vehicles, in this case buses, can be used as a power source when they are parked.
The 28 buses that are currently being tested have the potential to return more than one megawatt of energy to the local power grid. If they were electrified, the total fleet of 9,000 London buses, could provide enough energy to power 150,000 homes. And the goal of the current experiment is to confirm that this is not only possible in London, but also in other large cities.
To date, V2G charging has mainly been pioneered by automakers, among them Renault, Nissan and Mitsubishi, which are already proposing V2G systems in Asia in partnership with local authorities and companies. In Europe, Renault has also embarked on a large-scale experiment in the Netherlands with an extensive fleet of V2G-compatible Renault Zoe electric automobiles, which began in 2019.