First Bus has become what it claims is the sector’s first operator to enrol depots into the National Grid balancing mechanism to support use of renewable energy in charging battery-electric fleets.
A trial has begun at Caledonia depot in Glasgow and will be extended to Great Yarmouth later. The application balances electricity supply and demand shortly before power delivery.
The First Bus contribution will see it flex how electric vehicles are charged to increase demand at times when excess renewable energy is within the grid – particularly wind power in Scotland – and reduce demand during peak periods. That will reduce the need to curtail wider renewable generation and support a more efficient and flexible network.
In Scotland, significant volumes of wind energy are generated, but grid capacity limitations can mean that some of it may not be transmitted to where demand is highest. Renewable energy is thus sometimes curtailed. By increasing their demand at key times, electric depots can help to absorb that excess, First Bus notes.
It is delivering the trial in partnership with Optimo Energy. The supplier’s platform enables operators to optimise charging in response to real-time grid signals while ensuring that buses remain ready for service.
The trial will also explore how depots can participate in additional energy flexibility markets, creating potential new revenue streams while supporting the wider transition to net-zero.
Speaking about the exercise, First Bus Chief Sustainability Officer Isabel McAllister says: “Electric buses are already transforming public transport, but this trial shows that they have the ability to go even further: playing an active role in the UK’s energy system.
“We have built significant electric capacity across our depots, and the next step is using it more intelligently. By charging when the grid needs us to, we can help to reduce wasted renewable energy, support system stability, and improve the overall economics of electrification.”
The group has over 1,400 zero-emission vehicles in service, representing around a quarter of its fleet. They are supported by a 20-strong estate of electric depots, with several more due for completion this year.
