Ground source heat pumps: a place in the UK renewables mix?

Ground source heat pumps (GSHP) use energy stored in the ground to heat and cool buildings, and provide hot water. Although the UK is lagging behind other European countries such as Sweden where this technology is commonplace, the market is rapidly expanding – doubling in the last year alone.

A UK perspective

The pumps are increasingly popular in London, where they have been used by developers to meet the Merton Rule, which requires large developments to build some onsite renewable energy generation. In the UK there are an estimated 8000 ground source heat pumps, but the report suggests that if the government introduces sufficient support for them, this could increase to over a million. The Renewable Heat Incentive – which will be introduced in 2012 and will pay homeowners and businesses a guaranteed price for generating renewable heat – will be the most important factor in determining how much the GSHP industry grows.

Rapidly growing technology

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% 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 the 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.”

The Environment Agency report

‘Ground source heating and cooling pumps: state of play and future trends’, was commissioned to assess the role ground source heating and cooling pumps could play in meeting the UK’s renewable energy targets.

Report findings: 

There are currently 8000 units installed in the UK, but the market is growing rapidly. Last year saw the market double in size with 4000 units installed. The majority of GSHPs are domestic units with a capacity of 4 - 12 kWth – enough to provide a typical home with heating and hot water.

There has been considerable growth in London, with open loop pumps being used to cool offices. 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.

In the ‘growth’ scenario there could be 320,000 GSHPs installed by 2020 – 1% of homes and 11% of commercial buildings.

In a ‘high growth’ scenario up to 1,200,000 units could be installed, heating 11% of homes and 40% of commercial buildings in the UK. This represents the extreme end of what could be possible.

The UK electricity distribution network would need to be upgraded in many instances to allow the installation of larger heat pumps.

The full report can be found on the Environment Agency website www.environment-agency.gov.uk

Read the article online at: https://www.oilfieldtechnology.com/drilling-and-production/09122009/ground_source_heat_pumps/