Agenda item

The Committee considered a report of the Corporate Director of Neighbourhoods and Climate Change which provided information on the opportunity with regard to taking heat from flooded, disused coal mines in County Durham, in advance of a presentation by the Net Zero Team Leader, Ellie Grimes and the Regeneration Projects Manager, Chris Myers (for copy of report and presentation see file of minutes).

The Committee noted that heat accounts for approximately half of the county’s and Council’s greenhouse gas emissions. The Net Zero Team Leader explained that heat networks are low carbon and source agnostic in that different sources can be used for example sewage, geothermal heat and industrial waste heat.

Advantages of heat networks were cited as price stability, energy security, the creation of skilled jobs and they bring the opportunity to address fuel poverty as heat networks can be up to 40% cheaper than air source heat pumps.  Disadvantages include that heat networks have a high capital cost and there are associated risks. 

The Committee noted that minewater heat networks are not appropriate for all areas and there may be more cost effective alternatives, for example where minewater is not already pumped to the surface for treatment.

The Net Zero Team Leader then explained how heat is recovered from minewater by pumping the water to the surface of a flooded mine at approximately 16 to 20 degrees Celsius and a heat exchanger recovers the heat which can then be distributed to homes.  Members were encouraged to view the North East Local Enterprise Partnership’s White Papers in relation to minewater and geothermal energy, for detailed information on the scale of the opportunities for the North East.

The Committee received information on various national and local enablers which are encouraging heat networks such as the government’s Net Zero Strategy.  The Heat Network Zoning Regulations are expected to be introduced in 2025 and the zoning will identify areas where heat networks are the lowest cost solution to decarbonising heat. The Coal Authority Business Plan aims to support at least five minewater heat networks by 2025-26.  Examples of local enablers include the Climate Emergency Response Plan, the County Durham Plan and the development of the Heat Network Strategy.

Chris Myers, Regeneration Projects Manager, provided details of live minewater heat projects. At Seaham Garden Village the plan is for a development of homes and commercial units to access the district heat network powered by minewater from the Dawdon pumping station. Water is pumped to the surface at 19-20 degrees Celsius, which is advantageous in terms of bringing the heat up to domestic heat levels. The agreement with the company running the network is that the heat must be provided at less cost than the counterfactual cost of an air source heat pump and therefore there will be a commercial advantage to connecting to the network. 

Members heard that feasibility and project development work is underway at the Horden project.  Opportunities at Durham city include consideration of geothermal sources.  A heat mapping study is underway with the Centre of Sustainable Energy to identify potential heat network zones in County Durham. The Net Zero Team Leader highlighted that sources require assessment and where a minewater scheme is of interest and minewater is not pumped to the surface, there would then be a need to drill in order to pump the water to the surface and the drilling process poses risks. The Committee noted the Coal Authority has a remit to treat minewater to remove heavy metals. The Regeneration Projects Manager informed the Committee that, at the Dawdon pumping station, the Coal Authority cleans heavy metals to create iron ochre which is used as a byproduct in anaerobic digestion.

The Chair thanked the officers for the presentation and invited questions from the Committee.

In response to a question from Mr Walton regarding how minewater heat networks are more cost effective than air source heat pumps, the Regeneration Projects Manager explained that, air source heat pumps are required to heat water from lower temperatures than minewater which is geothermally warmed to approximately 20 degrees Celsius.

Councillor McLean praised the excellent work done to progress the minewater heat project at Horden which contributed to securing funding for the project development works. He commented that he is hoping to see further investment for the next stage of the project.

Councillor Adam asked whether the Coal Authority has a mapping system which can identify mines where drilling is not required. The Net Zero Team Leader clarified that Coal Authority maps identify where minewater pumping stations are located in the county and the information is fed into the Heat Network Study. However mapping information can be outdated and does not always accurately reflect how mines were decommissioned. 

Councillor Wilkes referred to the North East devolution deal which provides funding opportunities and the potential for private sector funding. The NetZero Team Leader highlighted grant support is available for the devleopment of heat networks through the Heat Networks Delivery Unit; the Green Heat Network Fund, which provides capital grants for commercialisation and construction, and BHIVE which is designed to assist public sector schemes to attract private sector investment. The Project Manager referred to the requirement to provide a business case in order to access government funding and commented that government funding was imperative in enabling the scheme at Seaham Garden Village.

Resolved:

The Environment and Sustainable Communities Overview and Scrutiny Committee noted the potential for heat networks across the County.