Heat Pump Case Studies: GSHP in Barn Conversion

Property Type: 5-bedroom barn conversion in Macclesfield

Product installed: IVT Ground Source Heat Pump

Distribution system: Radiators

Installation date: 2006

Cost savings: Mark estimates he is not spending £1,800 on LPG compared with the use of electricity for his ground source heat pump. He is expecting to generate approximately £1,500 income from his solar photovoltaic (solar PV) panels in the first year (over £750 to date).

Back in 2001, Mark Boothby moved into a 5-bedroom home near Macclesfield that had recently been converted from a number of farm outbuildings. There was no mains gas but initially at 12 pence per litre for LPG his fuel bills were modest. In 2005 he was 'inspired' while watching the 'Tonight' program when he saw how a headmaster had installed a ground source heat pump at his school. It appeared that not only could Mark reduce his fuel bills but also the environmental impact from heating his home in a similar way. So in June 2006, work began on the groundworks for installation of a ground source heat pump.

Mark was previously heating the property with two LPG boilers which were now not only expensive but were also calculated as producing 11.9 tonnes of CO2 per annum. These were costing over £340 per month to run during the winter and rising year on year. The ground source heat pump would provide all the heating and hot water requirements 24/7 for Mark's home via pipes buried in the ground known as a Ground Loop.

The pipe work which comprises the groundworks for Mark's installation consists of three ground loops buried in three 200 metre narrow trenches dug (with a chain trencher) to a depth of 1 metre in less than a day. The trenches were backfilled on day 2 and the ground loops pressure tested to ensure there was no leakage in the pipes. As you can see from the image on the left, even at this early stage there was minimal disruption to the ground. Following completion of the groundworks, work began on the installation of the heat pump.

Although at the time a plumber Mark had consulted said he must be mad as he would use the system to heat existing radiators, Mark stood by his decision to install a heat pump and work commenced. Following installation of the heat pump, Ice Energy engineers returned to the property for commissioning. As well as ensuring the heat pump had been correctly installed, this involved the pumping of glycol which is a type of antifreeze, through the ground loop.

This glycol and water mixture is then gently pumped through the pipes, warmed by the soil around it and fed through the heat pump where it is put through a process to heat the water to 65 degrees C. Mark's heat pump has now been installed for over six years and continues to provide instant hot water at the end of the house - some 40 metres from the heat pump itself. The continued performance of the heat pump is one of the major benefits of the technology and Mark remains pleased with his decision to switch to a renewable energy heating solution. "The heat pump is a long term investment I made not only for the longer term environmental benefit, but also to significantly reduce my heating bills. Furthermore, I am no longer tied to one supplier for the majority of my energy needs and no annual maintenance is required. I feel I have definitely proved the plumber wrong!"

Mark has now expanded his renewable energy exposure by installing solar photovoltaic (solar PV) panels, also supplied and installed by Ice Energy. Installed in March 2012, the panels will help generate some of the electricity used to power Mark's heat pump further reducing his fuel bills as well as his carbon emissions. "I saw this very much as an opportunity to extend the environmentally-friendly nature of my property and the solar panels compliment the ground source heat pump ideally as they provide some of the power to it. I was also lucky enough to secure the Feed-in-Tariff rate of 43p which will provide an excellent return on investment as well as the panels themselves reducing my electricity bills, so all in all it was another great decision."

Summing up his experience of Ice Energy and renewables as a whole Mark said "I cannot stress enough just how much I have benefitted from my heat pump. The cost savings alone have been substantial not to mention a constantly warm and comfortable home. The service from Ice Energy has been excellent throughout and I would certainly recommend both them and their products to anyone seeking to reduce their fuel bills. I just called the LPG gas supplier who said it will now cost me 75 pence per litre."

Mark is passionate about renewables. He is also one of the founding shareholders of MGC3 - a clean technology focused fund management company: www.mqc3.com

Solutions Used

  • IVT ground source heat pump connected via three, 200 metre, 30 centimetre wide trenches at a depth of 1 metre
  • 16 panel, 4kW Solar Photovoltaic (Solar PV) array

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