Keltbray today reveals it has saved 407kgs of CO2 using the Falcon Tower Crane Services Ltd supplied PUNCH Flybrid system, to power its crane requirements at the Chiltern tunnels, Little Missenden shaft site, being constructed by the Align joint venture as part of HS2 Phase One.

Silverstone Park based engineering specialist PUNCH Flybrid has developed an innovative energy storage system, using flywheel technology. It allows us to significantly reduce the generator required to power the tower crane from a 250kVA to a 150kVA. The significantly smaller 150kVA generator’s power difference is bridged by pairing it with an energy storing flywheel system. Falcon’s first PUNCH Flybrid system was rented to Keltbray on a HS2 project at Little Missenden earlier this year, as a temporary solution for one month until mains power was available.

This system has allowed Keltbray to reduce the capacity of the generator by 40% and reduces fuel demand by 50%.

Over the course of one month, whilst also utilising HVO fuel, Keltbray managed to reduce CO2 emissions on the project from 273kgs per week to 176kgs per week.

Kiro Tamer, Head of Environmental Sustainability at Keltbray said: “Keltbray is pleased to be using this innovative technology which provides significant carbon savings. Mains electricity is not always available on projects which means that for some operations generators are required. Operations which require electric motors can have a very high start-up current resulting in an oversized generator, this means that in normal operating conditions you have an under-loaded engine, which is bad news for fuel consumption and air quality.

The PUNCH Flybrid flywheel technology allows us to almost halve the size of the generator by working in the background and providing the inrush current when required. It’s fantastic to see how a technology used in Formula 1 to increase the efficiency of cars can also be applied to the construction industry to increase the efficiency of power generation and supply.”

Shaun Bonner, Tower Crane & Concrete Plant Manager at Keltbray said: “This is an exciting time for Keltbray to be introducing this fantastic innovation on a HS2 project. It shows our commitment to be open to new technologies that are beneficial for our communities and environment. We at Keltbray are really proud to run the PUNCH flywheel on one of our brand new Moritsch tower cranes to see the benefits from a lower carbon footprint and a saving in fuel efficiency. Many thanks to Falcon Tower Crane Services for their continued support in this development.”

Andrew Brown, Managing Director at Falcon Tower Crane Services Ltd said: “Our first PUNCH Flybrid system was rented to Keltbray on a HS2 project at Little Missenden earlier this year, as a temporary solution for one month until mains power was available. The PUNCH Flybrid, which was used in conjunction with HVO fuel, reduced the generator size from a 250kva to a 150kva, and over the course of the month saved 407kgs of CO2. Since the start of the year Falcon have purchased several systems to be used in conjunction with our tower cranes to reduce the size of the generator required.

The amount of CO2 saved is phenomenal, but so is the financial saving for our customers. A smaller generator is cheaper to rent and uses less fuel which exceeds the cost to rent the PUNCH Flybrid system. Historically, the more money you spend on energy saving products the less CO2 you produce. Our clients no longer must make this trade off. We can cut CO2 emissions, whilst saving money.”


Media Enquiries

Nina Platt, Corporate Communications Manager and Group Inclusion Manager

Keltbray Holdings Limited

Tel: 07395 792301

Email: [email protected]


Philip Pashley

Group Director, Corporate Communications

Keltbray Holdings Limited

Tel: 07860 954620

Email: [email protected]


Notes for Editors

About Keltbray

Keltbray is a leading multi-disciplinary engineering and construction services business, offering a uniquely integrated delivery capability spanning key phases of the client value chain.

Keltbray provides certainty of outcome for prestigious public and private sector clients often in highly regulated markets like rail and energy, contributing to the development and maintenance of Britain’s rapidly changing economic and social infrastructure.

Our professionally accredited teams of engineering and construction professionals take pride in delivering safely and sustainably to enhance, upgrade and decarbonise our clients’ capital assets.