Portable, low emissions underground power solution

“Energyst makes custom solutions feel  as easy and carefree as standard ones”

Peter Pearson, BAM UK

To facilitate work in the transport tunnel, BFK asked Energyst for portable power.

This presented Energyst with big challenges regarding safety, health and logistics. As Energyst’s Sales Manager Alex Thomas puts it: “UK rail company Crossrail had raised the standards of safety and environmental impact in London, stating diesel particulates and NOx given off by all diesel machinery must be kept to a minimum.

Clearly, standard generators were not an option.

All generators on the project had to be modified to comply with the new health and safety regulations.” On a logistics level, there was another challenge Energyst had to take on: how to move four 250kVA generators up and down the tunnel as work progressed. And of course, working underground does not make things easier for the on-going servicing of the generators. Without a telephone signal, the lines of communication are limited.

“UK rail company Crossrail had raised the standards of safety and environmental impact in London”

Alex Thomas
Sales Manager at Energyst UK

The need for underground mobility was solved by having four trolleys.

The trolleys were constructed locally, strong enough to hold the generators, and set up so they could be pulled up and down from each end of the tunnel to where they were needed. Three of the trolleys have already been put to work. Borrowing on the tunnelling tradition of assigning girls’ names to drills, the trolleys too were christened: Milly, Tilly, and Lily.

To meet increasingly stringent health, safety, and sustainability regulations, all of the generator sets were retrospectively fitted with diesel particulate filters, to reduce emissions. Again, the work was carried out on location, inside the tunnel, to save time and keep within tight deadlines.

In the second part of the project, Energyst installed a custom-made power generator solution.

A power solution that would function as the mains supply for six months. Why it had to be custom-made? Due to space limitations on the surface. these generators had to be placed 35 metres below ground, operated with a remote fuel system to reduce the risk of large quantities of fuel underground, and to limit the environmental impact. These machines operate on a ‘load on demand’ basis, enabling the customer to vary loading according to actual demand.


How can we bring Real Energy to your world?

To find out more about our design and engineering expertise, or to ask our advice on power, heating or cooling, contact your nearest Energyst rental location or simply call 00800 3637 4978. We will put all our energy into helping you find the right solution.

Tunnel photo courtesy of BFK

Technical specifications

  • Part 1: Four, locally constructed mobile trolleys for the 4x 250 kVA generators. These generators were modified to be compliant with Emission Regulations NRMM rated 37 – 560kW, regulating operation inside tunnels. The retro-fitted gensets with diesel particulate filters were modified inside the tunnel.
  • Part 2: 3x 500 kVA machines with the same modifications, to function as the mains supply for six months of the project.
  • Project duration: The Crossrail 1 project began in 2012 and will finish in 2017, followed by Crossrail 2.


Energyst engaged intensively with BKF to first understand their precise requirements, to help them stay ahead of the game, where safety and emissions regulations are concerned: “One year of constant heavy drilling, and not a single second of downtime”.



Energyst is a CAT Rental Company for power generation and temperature control. But most of all: we are a group of people that bring their personal and professional energy to every project in every part of the world.


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