Update on Hebburn Renewable Energy Scheme
A renewable energy project in South Tyneside cannot progress in its current form.
The Hebburn Minewater Scheme, which aimed to draw geothermal energy from abandoned flooded mines, must change direction due to stability issues with one of the boreholes.
This means the water cannot be extracted and returned to the mine workings as intended.
The carbon-cutting scheme will still go ahead, however air source heat pumps will be used instead of minewater pumps, a mitigating measure which had already been designed into the system.
It is likely that the revised scheme will result in the same estimated annual carbon savings of approximately 319 tonnes.
Cllr Margaret Meling, Lead Member for Economic Growth, Skills and Climate Change, said: "We are naturally very disappointed, but we are still committed to generating modern energy solutions using our historical and natural resources.
"Unfortunately, there are no tests or surveys which would have allowed us to foresee this issue; we had to rely on historic maps, which don't detail the intricacies of the mine workings.
"With innovation there is inevitably an element of risk, for which we have mitigated, and we will take the learning from this scheme to continue to develop pioneering renewable energy systems.
"A revised scheme will use air source heat pumps to feed into the energy centre, which will then provide low carbon heat to residents and council buildings via a pipe network, as planned.
Following the drilling of pilot boreholes, contractors Dunelm Geotechnical and Environmental had been working to construct wider abstraction and reinjection boreholes for the permanent drill casings.
Whilst one borehole was widened successfully, stability issues were discovered in the second borehole at a depth of 168mm, preventing the well from reaching its target depth of 300m and being used as intended.
Cllr Meling added: "We are still keen to use minewater as an energy source as part of this scheme and are exploring the option of extracting and reinjecting using the same borehole, however this will result in less output from the minewater than was originally intended.
"Any minewater that we can use will complement the output from the air source heat pumps."
Electricity generated locally using solar panels and a Combined Heat and Power Unit will be used to help power the system.