Fail-safe power for rail signalling centre

Load sharing generators provide critical power for Thames Valley Signalling Centre


Thames Valley Signalling Centre is on a busy mainline rail network, relied on by thousands of commuters and travelers every day.  The site depends on continuous power to ensure the network operates effectively, so when Network Rail needed to upgrade a breaker in their switchgear at the signalling centre, they called on Aggreko to provide prime power for the site while it was taken off-grid.

Without mains power it was critical for Aggreko to provide a fail-safe, so the signalling centre could remain online and the main Western train line could operate as usual.  

Aggreko’s generators, on a load sharing set-up, ensured a reliable power source and prevented any rail disruption.

Aggreko solution

Although Network Rail had a standby generator onsite, this was unfortunately linked to the switchgear that had to be upgraded, making it obsolete for this project.  Aggreko therefore needed to provide both prime power and a back-up to ensure the signalling centre remained operational to maintain the train line. 

We installed two 800 kVA generators set up on a load sharing basis. This meant both generators shared the site’s 500 kVA power load, with the spare capacity to take the whole load should one of them fail.  We also ensured there was always a reliable amount of fuel. We supplied three fuel tanks, one of which contained a back-up supply, and provided a fuel management service with regular fuel deliveries.  

Space was limited at this site, so we delivered the generators on a trailer and organised a crane to lift them into position. We installed the kit within four hours and then smoothly transitioned off the grid to our generators.  As soon as the switchgear upgrading was completed, we moved the power source back to the grid and removed the generators, making the project as hassle free as possible. 


With Thames Valley Signalling Centre being on such a busy mainline rail network, is was imperative that the site had continuous power while the switchgear upgrade took place.  Aggreko’s generators, on a load sharing set-up, ensured a reliable power source and prevented any rail disruption.