Storing waste heat underground to improve system efficiencies
Summary REHAU can provide a borehole thermal energy storage (BTES) solution where waste industrial heat can be stored in boreholes, to later be extracted from the ground to go into the existing district energy system. This increases the efficiency of the district heating sytem (carbon savings potential) and also prevents waste heat being ejected wastefully into the atmosphere.
Problem Sheffield has a large amount of industrial waste heat which is currently not utilisied and in many cases, ejected into the atmosphere. This heat could instead be reused for space heating and hot water via seasonal storage heat underground.
REHAU can offer a borehole thermal energy storage (BTES) solution through our partners which allows excess heat to be stored in boreholes underground, and then extracted from the ground when needed (e.g. for heat users on the district heating network). Normal PE 100 pipework for boreholes is only resistant to +40C. REHAU manufacture PE-Xa probes which are suitable for high temperature storage at temperatures up to 95C, ideal for industrial waste heat. REHAU have experience of BTES schemes in UK, Denmark, Canada and Germany. Examples are attached with this submission.
REHAU have also many years of district heating network design across Europe and now manufacture district heating pipework in the UK. Using this experience can help optimise the efficiency of the BTES system through suitable pipe sizing and reducing heat losses.
Impact on economy
The industrial heat users, which currently eject the waste heat into the atmosphere, could actually sell their heat back into the district heating scheme and create a future income stream.
REHAU's district heating pipework is also made in the UK, so would support the UK economy.
Impact on culture This innovative energy efficient BTES solution would contribute towards Sheffield's carbon reduction targets and also continue to help the district heating system reduce fuel poverty in the region.
Impact on ecology Using the waste heat for space heating and hot water (via a borehole thermal energy storage system) would significantly improve the efficiency of a district heating system. Less heat would be wasted into the atmosphere, therefore reducing the demand on the district heating source, which is often a gas fired CHP.
Impact on politics Using a innovative borehole thermal energy storage (BTES) system across a prominent UK town would further increase the green credential of Sheffield itself and the local authority.