Seaham mine water heat network wins Gamechanger Award at Accelerate to Zero Awards

The Seaham Garden Village mine water heat network has won the Gamechanger Award at the 2026 Accelerate to Zero Awards, the Mining Remediation Authority announced on 10 November, five weeks after it declared the scheme fully operational.

The award was presented on Thursday 5 November at a ceremony held as part of BE-ST Fest in Glasgow. The authority said judges chose the scheme from projects across the UK.

The network uses water pumped from the authority's Dawdon mine water treatment scheme. According to the award release, the water is naturally between 18°C and 20°C, and a 733kW water source heat pump raises its temperature before the heat is distributed to 750 affordable homes.

Andrew Simpson, head of innovation, by-products and service delivery at the Mining Remediation Authority, said: "The scheme shows what's possible when we put a former coalfield's mining legacy to work for the community."

The partners

Durham County Council, the Mining Remediation Authority, Karbon Homes and Vital Energi developed the network together, the authority said. Vital Energi designed and built the energy centre and network, and was appointed to operate the district heat network for 40 years.

Kieran Walsh, regional manager for Vital Energi, said: "It gives the infrastructure at Dawdon Colliery a new purpose, providing low-carbon heat for the surrounding area."

Vital Energi is also acting as the long-term energy services company, providing the heating and supporting customers, Walsh said.

BE-ST, which runs the awards, lists the winner of the Gamechanger Award, sponsored by Ryden, as Vital Energi, without naming the project. According to BE-ST, the ceremony at voco Grand Central in Glasgow drew more than 200 people from the built environment and construction sectors, with 11 categories presented. Vital Energi sponsored the Community Champion Award at the same event.

The timeline

Construction of the Seaham Energy Centre began in March 2025, the authority announced at the time. Vital Energi said then that the energy centre was being built directly next to the Dawdon treatment scheme and that building the centre and house connections was expected to take about four months.

Esh Construction, which is delivering the 750 affordable homes on behalf of Karbon Homes, said in July 2026 that the first homes were handed over to Karbon in December 2025 and that 49 homes had been completed and had welcomed residents. All of the homes are to be heated by the network, Esh said.

On 6 October 2026 the authority announced that the energy centre had completed commissioning and the network was fully operational. That release described the energy centre as using heat exchangers and a heat pump to extract and boost heat from the mine water, and said the scheme received funding through the government's Heat Networks Investment Project.

The two releases give different carbon figures. The October go-live release put the estimated saving at 2,600 tonnes of CO2 a year, equating to nearly 65,000 tonnes over the longer term, while the November award release said the scheme is expected to save 505 tonnes of carbon emissions a year.

The site

Dawdon Colliery began producing coal in 1904 and operated for 85 years, the authority said. After closure the workings filled with groundwater, rainwater and seawater, and the treatment scheme pumps and treats that water to protect the local aquifer. The authority said the heat network does not alter that role but gives the site a second use.

Seaham Garden Village forms part of a wider masterplan for 1,500 homes. Vital Energi said the village also includes a new primary school, village centre and innovation hubs, to be built over the next 10 years.

Karbon Homes was confirmed as the first user of the network. Paul Fiddaman, chief executive of Karbon Homes, said the homes, fitted with solar PV panels and other energy efficiency technologies, would be well on the way to net zero.

The precedent

The UK's earlier large-scale mine water heat network, in Gateshead, began supplying heat to homes and businesses in March 2023, the authority said. The Gateshead projects used boreholes drilled up to 150 metres underground, whereas Seaham draws on an existing treatment scheme.

The authority operates more than 80 mine water treatment schemes across Great Britain and said an estimated 25% of Great Britain's homes and businesses sit above former coal mines. It said Seaham shows how its existing infrastructure could also provide low-carbon heat.

Vital Energi's operating contract for the Seaham network runs for 40 years.