A Kier and Environment Agency trial of solar and green hydrogen energy in Somerset has yielded positive results in its early months.

The minimum 12-month trial is designed to explore whether solar power with a green hydrogen backup is a viable primary power supply on a construction site where access to mains electricity is not available.

The onsite welfare and office facilities at the Bridgwater Tidal Barrier scheme in Somerset were selected for the trial, with the hope that data will inform whether this approach is feasible and scalable for the demands of large-scale construction sites.

From the start of January to the end of April 2025, a total of 16,047 kWh has been used at the site - 6,588 kWh from solar power, 9,171 kWh from green hydrogen and 287 kWh from the back-up batteries.

When compared to an equivalent diesel generator to run the site with no additional interventions, the trial has generated estimated savings of around 20,000 litres of diesel, resulting in approximately 53,000 kgCO2e (carbon dioxide equivalent) avoided at the point of use.

That’s the equivalent savings of 195,000 miles in an average diesel car or 350 one-way flights from London to Glasgow.

The technology supplied to site aims to be zero emission at the point of use due to its combination of solar panels and hydrogen fuel cells.

Incorporating a battery that integrates with solar panels allows the system to convert energy directly into clean, renewable power, resulting in a continuous power supply. As well as contributing to a reduction in carbon emissions, it also reduces noise levels on site for both people and wildlife and avoids the potential spill risks associated with the alternative - generators.

Jo Driffield, senior engineer within the Environment Agency Innovation Team, said: “This early trial is critical to help understand the technology. Through our Innovation Fund, we are supporting Kier’s trial at the Bridgwater Tidal Barrier scheme with its innovation pairing solar with a hydrogen fuel cell back up at this scale of deployment.

“This trial is a big step forward to help the Environment Agency realise our net zero goals and a sustainable future. Conducting trials like this will demonstrate the demand for hydrogen, especially green hydrogen, which is needed to help support the investment into the production and supply to the construction industry and other uses.”

Hannah McIlroy, communications and sustainability director, Kier Natural Resources, Nuclear and Networks, added: “It is great to see how we are working so closely together with our clients and the supply chain to explore ways to collectively reduce our carbon emissions.

“I know that colleagues in Kier and the wider construction industry are keen to discover how our sustainable energy trial is progressing, and we are looking forward to sharing more."

By working closely together with specialists, TCP Group, learnings from the planning, initial setup and real-time tracking of energy usage data monitoring have already been applied.

This includes adding another fuel cell, using air conditioning units, and responding to requests from the site team to add energy usage data to site internal communication platforms as part of sharing performance and encouraging behavioural change.