Council reconsider heating buildings with mine water

Councillors have reconsidered a multi-million pound project designed to heat buildings with mine water after it was found to be too expensive.

Bridgend Council’s cabinet decided to progress with an alternative project after experts found more research was needed for the original plan, which would entail much higher costs than they expected.

Council leader Huw David said the scheme is “a very exciting project” that forms part of the council’s “responsibility around the climate change emergency”.

The original project, called the Caerau Heat Network, was supposed to provide low-carbon heat and cheaper energy bills for Caerau residents, costing £6.3 million in total, with the council spending £4.4 million in 2021-22.

It was hoped the scheme would use heat from water in former coal mines to create energy for heating and hot water in residents’ homes. The water would be transported to peoples’ homes through pipes with a ground source heat pump boosting the temperature to required levels.

In 2020, the Coal Authority found further investigations would be needed to determine if there is enough mine water in the area to support the project. To abstract and reinject boreholes as recommended by the authority it would cost £2.5 million, according to a report Janine Nightingale, the council’s corporate director for communities. This figure is over triple the previously estimated cost.

The report states council officers found “drilling to 400m depth through 12 mine workings is high risk with an uncertain outcome” and “given the budget available, it will not be possible to progress with further testing”.

Officers also concluded the project would not create enough revenue to cover the costs of further investigations, maintenance and replacing equipment in future. Given further testing is no longer an option, councillors agreed to stop investigating mine water as a potential source for the heat scheme.

Council officers recommended cabinet members to move ahead with a new plan, consisting of three small-scale low-carbon heating projects:

Heat Caerau Primary School with mine water (the project would not be connected to homes as per the original plan)
Connecting homes at the Tudor Estate to a small-scale heat pump based district heat network
Set up a private wire power supply (electricity) from Llynfi Afan Renewable Energy Park providing low-cost, low-carbon power
Councillors agreed to propose the new plan to WEFO during a meeting on Tuesday June 23. To receive money from the European Regional Development Fund (ERDF), the scheme must be complete by the end of June 2023.

Various stakeholders in the project include Welsh Government, UK Government, Cardiff University, Natural Resources Wales and The Coal Authority.

The total cost of the original scheme was £9.73 million. A grant of £7.3 million was approved by the ERDF, the council agreed to contribute £1.5 million, and £896,000 would come from other grants and service charges.

The revised project is expected to cost £9.72 million: £7.3 million from the ERDF, £1.5 million from the council, and £943,000 from other grants and service charges.