Midlothian Energy Limited (MEL), made up of Vattenfall Heat UK (part of Swedish energy company Vattenfall AB) and Midlothian Council, is to supply low-carbon heat through a network of underground pipes to newly built homes, which are being built in a former coal mining area.

Prior to the event at the National Mining Museum of Scotland in Newtongrange, a section of the district heating pipe was signed by the organisations making this project happen, before it was laid in the trench.

The initial phase of the network, which will supply around 3,000 homes, education and retail properties at Shawfair Town, will be powered by waste heat from the Millerhill Recycling and Energy Recovery Centre – an energy-from-waste plant operated by FCC Environment. This initial supply of heat will be the catalyst for a wider regional network stretching into south Edinburgh and East Lothian.

The Shawfair development is a key feature of the Midlothian Energy Limited five-year business plan to supply low-carbon heat to over 30,000 households and progress a variety of other energy projects. During the expansion of the district heating network, heat will be taken from other waste heat sources, including heat from the local mine workings.

The coal mines once supplied the energy and raw materials that powered industry in the 19th and 20th centuries, and the fuel to heat domestic properties. Once coal mines have closed and the pumps are stopped, they fill with water which is heated through natural geothermal processes. Heat can be transferred from the mine water to clean water in a district heating network to heat local homes and businesses.

Once a huge contributor to climate change, these coalfields are now being used to decarbonise heat supply supporting Scotland’s low carbon future. Midlothian Energy and Vattenfall Heat UK are working with the Coal Authority to explore using heat from a planned mine water treatment scheme at Dalkeith, one of several pioneering mine water heat projects under consideration in Scotland.

Construction of the district heating network started earlier this year and has been challenging due to the number of former mine shafts to be avoided in the area, but having these situated locally may eventually be an asset to the district heating infrastructure where we may be able to store energy.

Vattenfall Heat UK has employed Scottish company FES Group to deliver the low carbon heating at Shawfair Town, a development overseen by Shawfair LLP, in the north of the Midlothian Council area. This will be Vattenfall’s first heat project in Scotland and Midlothian Energy Limited’s flagship project. A large section of the 4km pipes have already been installed.

Heat is expected to be delivered to homes by June 2024. The initial phase of the network is expected to save over 2,500 tonnes of CO2 per year, the equivalent of taking 1,200 cars off the road. The project will benefit from up to £7.3m² from the Scottish Government’s Low Carbon Infrastructure Transformation Project (LCITP).

Jenny Curtis, managing director at Vattenfall Heat UK, said: “Without the rapid deployment of heat networks at scale it is simply not possible for Scotland to reach its ambitious net zero by 2045 targets.

“Using waste heat from sources like energy from waste plants and mine workings is a no-brainer. The heat is already there, all we need is the urgent deployment of low-carbon heating infrastructure to capture it and supply it to local residents and businesses.

“We are so excited to build on Midlothian’s proud heritage and make the shift to create a low-carbon, clean energy network for the local community, inspiring the next generation into low-carbon, local jobs.”

Midlothian Council’s cabinet member for Environment, Councillor Dianne Alexander, said: “We are delighted to reach this key milestone in our joint venture to deliver low carbon heat projects across the Midlothian Council area.

“Our innovative approach to working with a highly experienced partner will help Midlothian deliver on our ambitious net zero plans and contribute to reducing fuel poverty.”

Nick Waugh, director at Shawfair LLP, said: “Shawfair LLP takes immense pride in the rich mining heritage of our local community and is equally delighted to help facilitate the transition to a low-carbon heat source working with Midlothian Council and Vattenfall, introducing district heating at scale to our new housing. Part of a package of initiatives delivering a sustainable low-carbon environment and future proofing our new vibrant modern town.”

James Reid, FES energy operations director at FES Group, said: “The Shawfair Development is the start of a new era for Midlothian. FES Group believes the use of waste heat from the Millerhill recycling and energy recovery centre (RERC) and low carbon technologies in the MEL Energy Centre, will provide the catalyst for future generations to meet the challenge of net zero for Midlothian and the surrounding areas.

“The project demonstrates that business models such as MEL can bring experienced private businesses and local authorities together, providing value to local communities and the inspiration for more low carbon infrastructure schemes throughout Scotland. We are delighted that MEL has chosen FES Group to be Principal Contractor for this regenerative journey of the area.”

Steve Longdon, chief executive officer for FCC Environment, added: “Since 2019 the Millerhill recycling and energy recovery centre (RERC) has been converting non-recyclable household and business waste into heat and power. The plant was developed by us alongside The City of Edinburgh Council and Midlothian Council to help them divert 155,000 tonnes of waste from landfill each year and the facility is a key component in the Councils’ combined commitment to helping to reach the Scottish Government’s Zero Waste target.

“With Net Zero ever on the agenda and a pressing need to invest in UK based renewable power sources as we seek to move to a lower carbon future economy utilising the heat from this plant is vital. It is good to see that real progress is being made towards delivering low-cost, low-carbon heating to 170,000⁴ homes in the Midlothian and Edinburgh region and we are proud to be a part of this major step forward.”

Peter Wormald, principal heat and by-product manager at the Coal Authority, said: “The Coal Authority continue to support and facilitate access to mine water heat in the Midlothian area and are encouraged by the progress of the low-carbon district heating network for the Shawfair development. We look forward to continuing our work with Midlothian Energy Ltd and Vattenfall Heat UK to confirm the feasibility of adding mine water heat to the heat network.

“Scotland’s coalfield communities could be at the forefront of sustainable heating and cooling - creating green jobs, green skills and green innovation from the mines beneath, whilst making coalfield communities a key part of Scotland’s low-carbon future.”