Kent farm to grow low carbon fruit all year using heat from Europe’s largest river source heat pump

Making a commitment to sustainable farming, Clock House Farm has installed a river source heat pump to enable the production of fruit outside of the UK growing season, saving around 3,800 tonnes of CO2 emissions per year compared to gas heating.

The system involves the extraction of water from the River Medway which passes through a heat exchange and is discharged straight back into the river, having removed a couple of degrees of heat from the water.  A second loop then transfers this heat to the plant room’s six heat pumps to achieve a temperature of 45 degrees, which is then pumped through 50mm pipes above the soil, releasing heat into the greenhouses. Heated water is also stored in a giant tank as a backup, and to help avoid the consumption of electricity at times of peak demand when electricity is expensive. This heat store can keep heat flowing to the greenhouses for 2 - 8 hours, depending on outside temperatures and how much heat is needed.

Clock House Farm contracted Independent Connection Provider Energy and System Technical (EAST), to supply and install the electrical infrastructure to power the heat pumps, working with Vattenfall for later adoption of the high voltage network. The work took around 3 months to complete and involved EAST installing a new DNO substation as well as 2 new customer substations, 2 Wilson tier 2 200KVA transformers and associated switchgear. Now the installation is complete, Vattenfall IDNO has taken ownership of some parts of the new electrical network and will continue to provide the operations and maintenance. 

Stewart Dawson, Managing Director of Vattenfall Networks, said:

“The UK needs to electrify much of its food production to drive down greenhouse gas emissions. But it’s not as complicated as people might think, and Vattenfall can provide the funding and electrical infrastructure to enable food producers to switch away from using fossil fuels.

“Stronger electricity networks are the thread which tie the whole net-zero plan together.  Clock House Farm have seized the initiative and thanks to the innovative technology they’re now using, people can enjoy fruit from Kent with reduced impact on the environment.”

Oli Pascall, Managing Director of Clock House Farm said:

“Clock House Farm is committed to the delivery of quality fruit whilst observing the best-in-class sustainability management practices.  

“We are always seeking out environmentally responsible initiatives and are delighted to be working together with like-minded organisations who are committed to driving down greenhouse gas emissions.

“By growing fruit out of season, the UK is able to ensure less reliance on imported soft fruit, increasing UK food security and ultimately this also helps to reduce the carbon footprint.” 

Michael Delgudice Managing Director of Energy and System Technical, said:

“As businesses expand operations to meet demand, innovation is fundamental for opening new ways of utilising energy from local, natural and sustainable sources. This is critical for the future development of electricity networks across the UK.

"Introducing the added value that an IDNO offered alongside this innovative use of the river source heat pump system highlights the benefit of asset adoption and we were delighted to be involved in providing the new electricity network infrastructure to Clock House Farm for this prestigious project.”

Notes to Editor

Further information about the CIAT Hyrdociat heat pumps:
The river source heat pumps pass the water through a heat exchanger right next to the river. A second loop (with 500mm pipes buried underground) then transfers the water around 50m up to 6 CIAT Hydrociat heat pumps which increase and transfer the heat to a third loop at up to 50°C, which runs through 6.5 hectares of greenhouses in 50mm pipes which sit above the surface of the soil and release heat into the greenhouses.

The main heat pumps use 1MW of electricity to produce ~5MW of heat. The coefficient of performance can vary from 4.2 to 6, depending on outside temperatures.

Read more about Vattenfall IDNO here.