Renewable energy installation company Geothermique, based in Buckinghamshire, came across an interesting challenge when they were called to a historic property located close to the River Thames. The four bedroom family home was previously run on LPG, as mains gas was not available, but the owner Mike Tucker was looking for a more affordable way to provide heating and hot water for his property as he entered his retirement and was keen to find out if heat pumps were suitable. Mr Tucker had recently upgraded his character stone-built property with new insulation and double glazing, which meant that the heat pump system would be even more efficient. On his visit to the stunning waterside property, Robert Carter of Geothermique recognised its close proximity to the river and immediately thought of the greater efficiency levels that can be achieved by using the heat energy stored in water as part of a heat pump system. Mike, a qualified engineer, had worked with Danfoss products before so was aware of their quality and reliability. He admits to taking a “leap of faith” to replace his existing LPG system with something far more sustainable and energy efficient. Geothermique set about making plans for a water source heat pump and, even though this type of installation is still relatively rare in the UK, the company was confident about the high seasonal performance that they expected it would be able to deliver. Using a Danfoss DHP-L Opti Heat Pump, Geothermique designed an innovative system that would allow heat energy to be taken from a river water collection sump adjacent to the Thames. This used a submersible pump half a metre below the water table to supply the heat exchanger in an adjacent boathouse, three metres away. From there, an underground ‘brine’ circuit conveys the warm water 30 metres to the house, Robert Carter from Geothermique explains: “We looked at the different options and this proved to be the most cost effective in terms of performance. “The river water in this area has a consistently high temperature, which means that it optimises the running of the heat pump. This is the first time we have installed a water source heat pump system, but the installation went very smoothly and we are confident that the couple will reap the benefits for many years to come.” The Danfoss 12kW heat pump was specified for the property, with space heating supplied through the already installed over sized radiators. The heat pump also supplies the home’s hot water needs. Geothermique removed the existing old LPG boiler and hot water tank in the utility room and replaced it with a Danfoss heat pump within just a couple of days. This takes up less space whilst providing full heating and hot water requirements, including a booster immersion heater should the need arise. Geothermique explained to the homeowners that heat pumps are designed to provide lots of continuing ‘low grade’ heat, rather than the short bursts of high energy from fossil fuels. This is more energy efficient and means that they should be able to benefit from much lower running costs in the future. As in all installations, Geothermique pre-set the system to ensure optimum running efficiency to compensation for mild and improved weather. The end result was a happy homeowner with a more sustainable heating and hot water solution, with less reliance on fossil fuels. Mr Tucker is looking forward to the benefit of a more efficient system that provides consistently warm and comfortable temperatures for their home during even the coldest winters. Closed loop water source heat pumps are a tried and tested method in Scandinavia and other Northern European countries, where there are many properties located close to water. Danfoss Heat Pumps UK has built its reputation on manufacturing high quality heat pumps for both commercial and domestic applications. The company has a network of approved installers throughout the UK, which it supports through training, as well as with technical and design advice, commissioning and after-sales service. Geothermique has over 10 years’ experience in the design and installation of heat pump systems in the Midlands and South of England. The company supplies system designs, installations, and any required associated services to both residential and commercial building projects of any size.
