Possible solution for using power stations’ waste heat

The Energy Technologies Institute is to examine the feasibility of capturing waste heat from power stations and storing it underground for later use to warm homes and provide hot water.

The six-month £140,000 project will be led by consultants Buro Happold with input from Cambridge University, the British Geological Survey and IF Technology Group.

The UK’s total demand for heat is about 800TWh per year, which is about the same as the total amount released by all power generation and industrial processes as waste.

’Capturing even 10 per cent of waste heat would have a significant impact on the UK’s total carbon emissions and security of supply, helping reduce our need for large quantities of imported fuels in the winter months when prices are highest,’ said ETI chief executive Dr David Clarke.

One of the main obstacles for making use of waste heat is that it is not available at the same time and place as the demand for it. However, it is technically possible to store very large quantities of heat energy below ground in geological structures such as saline aquifers or disused mines.

’Many of the potential heat sources and storage areas are close to centres of population and could be used to support large-scale district heating schemes, but there are currently many uncertainties around the effectiveness, environmental impact and ultimate capacity of such systems in the UK,’ added Clarke.

The study will investigate the cost effectiveness and practicalities of storing large quantities of heat for long periods to meet a significant proportion of the UK’s winter demand; evaluate the practical limits for this type of storage; and investigate where in the country it could be most effectively used.

The project will be completed next summer, after which the ETI will evaluate the practicality of proceeding to a large-scale demonstration of this technology in a real-world application.