First Bus trials smart EV charging to balance the UK grid

First Bus, one of the UK's largest public transport operators, has begun a smart charging pilot at its electric bus depots. Rather than charging buses at fixed times, the system dynamically coordinates charging sessions to coincide with periods when renewable energy — such as wind and solar — is most abundant on the grid.

The approach addresses one of the central challenges of the energy transition: integrating variable renewable generation without destabilising the grid. By shifting demand to times of surplus clean power, First Bus's depots effectively act as flexible loads that absorb excess electricity which might otherwise be curtailed or wasted.

Electric bus fleets are well-suited to this kind of grid-responsive operation because their daily schedules are predictable and depot dwell times are long enough to allow flexible charging windows. This makes them a valuable tool for transmission system operators (TSOs) seeking to balance supply and demand in real time.

The trial reflects a broader European trend of using EV infrastructure — from private cars to commercial fleets — as active participants in grid management. If successful, the model could be replicated across other UK cities and adopted by operators across the EU, where electrification of public transport is accelerating rapidly.