This is copy of an article by Robin Coates, first written for Malvern Hillistic in December 2017.
This is an article about what at the moment is a speculative idea that explores how a problem may possibly be turned to a valuable local scheme for energy generation.
You may know the reservoir that is on the East side of the British Camp (Herefordshire Beacon). Many years ago this was built to store water and provide a header tank for Malvern’s water supply. It had its own treatment plant at the base of the dam. Some time ago it ceased being used for this purpose. We guess that this may have been as a safety precaution, we note that the water level has been kept low for some time or because treatment was centralised on a few large plants. Dams have quite rightly very rigorous inspection schemes for public safety reasons. The dam is owned by Severn Trent and if it is not being used for water supply it will be a financial burden with high maintenance costs. This will encourage Severn Trent to consider removing its water holding ability as a dam.
We pondered whether an alternative might be to create a pumped storage hydro-electric scheme. This would enable the dam to be a financial asset rather than a liability. It would work by releasing water from the dam into pipes that are linked to turbines at the bottom of the hill and then to a large pond. The turbines generate electricity at peak times. Then at off peak times, either cheap electricity at night or surplus daytime renewable energy is used to pump the water back up to the dam. To do this there needs to be another large pond at the bottom of the hill to store the water ready to be pumped back up.
For the electricity generating companies to provide us with peak power there are many power stations that operate for a very short time and therefore at very high cost. The payments made for this power are many multiples of the normal wholesale rate paid to generating companies.
As we change the mix of methods of generation from fossil fuels to renewables we need more storage solutions. Pumped storage hydro-electric is one of these. It needs rather special geography to be able to have two reservoirs with a big height difference and tends to be very capital intensive. In Malvern’s case at least we have the high level dam, easy access to the dam, pond, turbine and pump house site (this could also be below ground) and grid connections reasonable close.
It is possible that for safety reasons the existing dam can only be used half full but that is still plenty of water for peak power.
So it is a great idea but there are so many obstacles to overcome if this is to be realised. Initially it would need the full support of the AONB and the Malvern Hills Trust, Severn Trent Water, any other landowners, The Malvern Hills District Council Planners and local people. If there was at least tentative support from these areas then a major Feasibility Study would be needed to check the environmental, engineering and financial details. Raising funds for this wouldn’t be easy as there is always the risk that the scheme will not go ahead and an organisation would need to be created to commission the report and later on see the project through and become the operator.
Assuming all the agreements could be arranged and the environmental, engineering and financial feasibility is sound then it would be a case of raising the money to carry out the scheme. Wouldn’t it be wonderful if this could be funded by local residents. As we did with the much smaller and simpler Malvern Community Energy Coop for the Cube PV panels.
In a few years’ time there will be more local grids connected to the national grid and the local generation by renewables will be feeding our buildings at lower cost, might Malvern be one of these local grids. At Malvern Community Energy Coop we will be tentatively exploring the issues raised, no promises but what an exciting possibility.
If you would like to find out more, get involved or be kept up to date contact us on firstname.lastname@example.org