The world’s fastest circuit-breakers are now installed on London’s electricity network – and by 2050 they could save energy customers £400m and reduce the capital’s CO2 emissions by 3.8bn kg, equivalent to the emissions generated by 800,000 diesel or petrol-powered vehicles in one year. 

UK Power Networks has installed the world first Power Electronic Fault Limiting Circuit Breaker device at a substation in Tower Hamlets. The technology can detect and protect from a fault on the electricity network in just four-thousands of a second; 20 times faster than any existing circuit breakers.

The devices make it easier and cheaper for low carbon energy technologies such as wind, solar and Combined Heat and Power (CHP) units to connect to the grid. CHP – spinning turbines which produce both heat and electricity – is especially popular in big cities at places like hospitals and can play a crucial role in district heating and community energy projects.

The efficiency of CHP means the Greater London Authority aspires for CHP demand to rise by 500 per cent over the next 15 years. UK Power Networks is helping to enable this additional power to connect safely to the network while spending less of customers’ money on physical infrastructure upgrades. 

That is where Powerful-CB comes in. The super-fast circuit breaker will protect the network from any issues created by faults 250 times faster than a person can blink. As a result, more CHP and other low carbon generation can be safely connected a lower cost, and the benefits passed on to customers.

The devices are a quarter of the size and half the price of the current limiters being used.

Savings of up to £400m would be driven by an additional 460MW of distributed generation the device would facilitate connecting to the network. The increase in CHP has the potential to deliver up to 3.8bn kg of cumulative reduction in CO2 emissions by 2050. That is the equivalent of emissions generated by 800,000 petrol or diesel-powered vehicles in one year.

Powerful-CB devices are reusable, unlike fuses which perform a similar function. Engineers at UK Power Networks’ can also operate the devices remotely, meaning that the lights can be turned back on faster without needing to visit the site, should a fault occur. 

Device trials will continue until 2021 to gather data on Powerful-CB devices’ performance in different configurations. The £6.188m project is part of the Ofgem-funded Network Innovation Competition.