Why plugging ships into the grid can cost more than running onboard generators

What happened

The port has launched the UK’s first high-voltage, multi-berth installation, allowing docked ships to connect to grid electricity instead of generating power onboard. A ship can switch off its generators, burn less fuel and reduce pollution while docked, yet still face a higher power bill.

That is the financial challenge surrounding Portsmouth International Port’s new shore power system. It provides support for Portsmouth’s ambition to become a net-zero facility, improve local air quality and contribute to the wider decarbonization of shipping.

However, high UK electricity prices complicate the economics. Shore power can replace fuel-burning generators without delivering the savings operators might expect, while rising grid-related charges add further pressure.