Kier’s Clean Energy Trial Bears Fruit: What It Means for the Future of Site Power

Kier, one of the UK’s leading contractors, has taken another step toward greener construction with a landmark trial at its active site in London. The company’s latest pilot, focused on replacing diesel generators with a hybrid hydrogen-battery power solution, shows real promise for decarbonising the way UK construction sites operate.

The Kier Energy Trial: What Was Tested?

At a live project in the heart of London, Kier deployed a modular energy system that combined a hydrogen fuel cell with lithium-ion batteries. The trial, delivered in partnership with AFC Energy and supported by other energy specialists, aimed to test whether this setup could provide reliable, low-carbon power for site cabins, welfare facilities, and small equipment.

Key stats from the trial:

• Carbon savings: Over 3 tonnes of CO₂ emissions avoided in just 4 weeks

• Zero on-site emissions: No NOx or particulate pollution during operation

• Noise: Dramatic reduction, especially during overnight periods

The system proved fully capable of supporting the site’s power needs, with seamless switchover between battery and hydrogen sources. Kier’s project team reported zero disruption to normal operations.

Delivery Partners

• AFC Energy: Hydrogen fuel cell technology provider

• Sunbelt Rentals: Battery storage and site equipment supply

• Kier’s Energy & Carbon team: Led project management and site integration

Risk Analysis

Technical Risks:

• Hydrogen logistics: Ensuring a steady and safe supply of hydrogen was critical; the project sourced green hydrogen, delivered and stored according to UK safety standards.

• Integration: Matching power output to site demand required precise load management, which was achieved using advanced monitoring.

Operational Risks:

• Staff needed training on hydrogen safety, and a robust risk assessment was carried out.

• Temporary disruptions could have occurred during system changeover, but none were reported.

Commercial Risks:

• The up-front cost of hydrogen and batteries remains higher than diesel, but savings on carbon costs and growing government incentives are closing the gap.

Impact Analysis

Environmental Impact:

• Significant CO₂ reduction compared to diesel use

• Elimination of diesel exhaust emissions (NOx, particulates)

• Less noise pollution, improving the working environment for staff and local residents

Operational Impact:

• Demonstrated reliability, supporting critical site operations without downtime

• Paves the way for wider adoption of low-carbon site power solutions in major cities

Sector Impact:

• Kier’s successful trial may encourage other contractors to accelerate their own decarbonisation plans

• Shows clients and regulators that net zero targets are achievable, even on complex city-centre projects

What’s Next for Kier and Clean Construction?

Following the positive results, Kier is now looking to roll out this hybrid hydrogen-battery approach to other sites. The company sees this technology as a key pillar in its roadmap to net zero, aiming for significant carbon savings across its portfolio by 2030.

More broadly, the UK construction sector is watching closely. With carbon pricing and environmental standards tightening, innovations like Kier’s energy trial could quickly become best practice.