Minewater district heating works by extracting energy from the floodwater in disused coal mines, which is heated by geothermal processes, and upgrading it using heat pumps to supply a district heat network using insulated pipes conveying hot water around a town centre. Public, commercial and residential buildings can all be supplied with heat from such a system.
Like many towns in Northern England, Oldham has an extensive network of disused coal mines underneath the town centre, dating back to the Industrial Revolution. If the principle of minewater heat can be shown to work in Oldham, it could open up the potential for this clean energy technology to supply town centres anywhere where this industrial heritage exists.
Working together with the UK government's Department for Business, Energy and Industrial Strategy, Oldham Council officers commissioned specialist consultants and the UK Coal Authority to carry out feasibility work looking at the potential for a minewater heat network. The feasibility study showed that a 4MW minewater heat network could be feasible, supplying large town centre buildings such as Spindles Shopping Centre, Oldham Leisure Centre, and a wide range of other commercial and residential buildings including homes on the nearby St Mary's social housing estate, owned by First Choice Homes Oldham (FCHO).
FCHO already own a district heat network at St Mary's, and the feasibility work showed that this could be linked up with a new minewater heat network to serve the whole of Oldham town centre plus the St Mary's social homes. This potential wide-scale heat network could be expanded even further in the future. The existing First Choice Homes energy centre at St Mary's houses 3.5MW of biomass boilers which could also be used to provide additional heat for the low carbon heat network.
Oldham Council and First Choice Homes are now looking to work together on the next stage of technical and economic feasibility to see if they can make the new low carbon heat network a reality. Key to this will be the drilling of test minewater boreholes, which will be the next big step towards the realisation of a low carbon Oldham Town Centre.
For anyone wondering whether a minewater district heating scheme would be suitable for their town, the obvious first place to start is to look at the industrial heritage of the town and whether there are disused coal mines underneath the town centre. Many towns used to have their own central power station and the mines would have been nearby. In the UK, the Coal Authority (formerly the National Coal Board) which owns the disused mineworkings can be contacted about this and are keen to promote minewater heating as a renewable energy source for the future, so they have an interest in supporting any feasibility work.
There are examples of working and new minewater district heating schemes in Europe and the UK – more local authorities are looking at these schemes all the time so there is an increasing resource of information and experience around this. Local authorities developing such schemes may be willing to talk about work done so far and their learning from it.
Minewater heating schemes generally may not affect communities directly but local environmental groups may have an interest, so engaging with these local green groups and answering any questions they may have about the technology can help to gain their support. Local town centre businesses do have an interest though, so engaging with major building owners is essential to gauge interest and glean technical information about energy use for the feasibility work.
Getting the support of central government is also essential – in the UK, the Department of Business, Energy and Industrial Strategy is very supportive of Oldham’s scheme, and can provide not only grant funding assistance but expertise and professional guidance as to how to go about developing a minewater district heating scheme. Co-ordination with Greater Manchester Combined Authority has also been valuable as Oldham has benefited from feasibility work carried out as part of the DEEP Cities project which Greater Manchester is included in.
Consideration of strategic partners in the town can also prove hugely beneficial – in Oldham, the Council is now working together with the borough’s largest housing provider First Choice Homes to develop a new wide-scale district heat network which could incorporate minewater heat. Combining efforts in this way could result in a much larger and commercially attractive scheme than if the Council had simply pursued development of a new town centre heat network on its own.
- Amount of renewable heat being produced from the minewater heat pumps (estimated at 4MW).
- Amount of carbon savings from buildings connected to the heat network (estimated at 2630 tonnes per year).
- Amount of money the customers are saving on their heating bills compared to if they were using gas (yet to be calculated).
- Number of buildings/businesses connected to the heat network.