The '13-Amp' Bottleneck
Addressing the power grid bottleneck in London's electric bus transition through Integrated Bus and Charging Schedule Optimization.
A recent report in The Standard highlights a critical barrier to London’s 2030 electric bus targets: the power grid limitations at depots. First Bus MD Bill Cahill warns that upgrading depots involves massive lead times for high-voltage connections, making full fleet conversion seem "impossible" under current trajectories.
News Source: 'You don’t plug an electric bus into a 13amp socket' - bus chief says Sadiq Khan plan is impossible by 2030 (Evening Standard, 04 Jan 2026)
The Infrastructure Bottleneck
The core of the issue is the physical requirement for charging. As Cahill puts it, "You don’t plug an electric bus into a 13amp socket." Converting a traditional diesel depot into a high-capacity electric charging hub requires significant grid upgrades that often lag behind policy ambitions.
An Optimsation Perspective
This bottleneck presents a textbook case for Charging Infrastructure Planning. When physical grid upgrades are delayed, the solution must shift from civil engineering to mathematical optimsation.
Even with limited infrastructure, operators can maintain momentum through Integrated Bus and Charging Schedule Optimsation. By incorporating State-of-Charge (SoC) constraints directly into the timetabling phase, we can:
- Maximize Utilization: Efficiently rotate buses through limited charging points.
- Peak Shaving: Schedule charging to avoid overwhelming the local grid during high-demand periods.
- Joint Balancing: Treat electrification as a joint optimsation problem where grid constraints and passenger demand are balanced simultaneously.
This approach acknowledges the tight coupling between transportation and energy networks—a key focus of our current research at the lab.
This post is part of my OptiTransit Commentary series, where I apply academic rigour to public transport news.