Ground could deliver third of UK renewable heat targets

The UK has to meet renewable heat targets of 15 per cent by 2020 and currently has an estimated 8,000 GSHP installed, the majority of which are domestic units with enough capacity to provide a typical home with heating and hot water. The Environment Agency report – entitled ‘Ground Source Heating And Cooling Pumps: State Of Play And Future Trends’ – predicts that figure could rise to over one million if the Government introduces sufficient support for them. The forthcoming 2012 Renewable Heat Incentive, which will pay homeowners and businesses a guaranteed price for generating renewable heat, could be the most important factor in determining how much the GSHP industry grows, according to the report.

GSHP use energy stored in the ground and groundwater to heat and cool buildings, and provide hot water. There are two types of GSHP technology: open loop pumps, which extract water from an underground well, pump it through a heat exchanger and back underground through a second well, and closed loop pumps, which consist of a closed piping system buried in the ground and filled with water and anti-freeze. When the liquid travels around the pipe loops it absorbs heat from the ground.

Heat pumps are not carbon neutral, as they need electricity to drive the pump, but they typically generate three or four times the energy used to drive the system.

The Environment Agency says GSHPs have no negative impacts on the environment when installed, but says there are a number of barriers to growth in the ground source pump market from now until 2020 that need to be addressed if the potential for GSHPs is to be fully exploited. These include a UK electricity distribution network that is not built to take on large heat pumps and a gas distribution network that is currently cheaper to use for households. There are also higher costs associated with GSHPs than some other heating systems, particularly when retro-fitted. Meanwhile, if demand increases rapidly, there may be insufficient installers to carry out the work. Awareness also needs to be built up amongst consumers about the technology and its benefits.

Although last year, the GSHP market doubled in size with 4000 units installed, the UK is lagging behind other European countries such as Sweden where this technology is commonplace. However, the pumps are becoming increasingly popular with London property developers looking to meet the ‘Merton Rule’, whereby large developments are required to build some on-site renewable energy generation and open loop pump technology is being used to cool offices.

Tony Grayling, head of Climate Change and Sustainable Development at the Environment Agency said: “Ground source heating is a rapidly growing technology that has the potential to produce at least 30 per cent of the country’s renewable heat needs, but it needs financial support in order to grow. We would like to see this technology given adequate financial support through the new renewable heat incentive to meet its full potential in the UK.

"We have ambitious emissions reduction targets in UK, and the Environment Agency would like to see rapid growth of all low carbon energy technologies to help meet these. Any delays in reducing emissions will lead to more severe impacts of climate change.”