A £6.5m grant has been awarded to pump naturally-heated water from an Caerau coal mine (Maesteg) and use it to heat 150 homes. The technology developed will pump water from a depth of 230m (750ft) which has been heated by the earth to about 20.6C (70F).
SPECIFIC are assessing the heating energy demand for a cross section of the Caerau community and evaluating the potential for integration of renewable energy technologies. The feasibility study that this work contributes to is being delivered by a large commercial and academic consortium on behalf of Bridgend council. (to be completed at the end of February)
SPECIFIC is also working in conjunction with Cardiff Metropolitan University to assess the heating energy demand using a combination of surveying techniques, including condition assessments, air permeability tests, SAP calculations and thermography surveys. The information gained will underpin previous heat mapping work conducted by Cardiff university and inform the size of heat pump required.
Heat pumps use electricity to boost the temperature from a low temperature heat source (water from the mine), to provide space heating and hot water, thereby removing the need for a gas boiler. The integration of solar renewable technology and energy storage could help to offset household heating demand – saving each household up to £100 a year – as well as reduce the increased demand on grid electricity through locally generated renewable electricity.
Construction work is expected to start in 2020 with the first 150 homes being heated by winter 2021.
How does it work?
- Warm water is pumped from the mine
- It goes through a heat exchanger unit, a device about the size of a fridge which is fitted in people’s homes
- The heat from the exchanger is passed through a heat pump which in turn warms the water used in central heating
- Mine water does not enter people’s central heating and is pumped back underground so it can heat back up and be reused
[Source: BBC News]