The owners of a new-build home in Farnham, Surrey were very keen to achieve energy security, whilst also protecting themselves from future rises in fossil fuel prices and carbon taxation. Viessmann installation partner, isoenergy, proposed a ground source heat pump to generate 100 per cent of the property’s heating and hot water. The installation is saving around £1,000 per annum at present, but will increase once the outdoor swimming pool is commissioned.
Grovers Cottage is intended to be used as a long term, permanent residence, and this allowed investment in energy infrastructure to play a huge part in the building project decision-making process. Local installer, isoenergy, recommended that as the property was situated on ample land, a ground source heat pump would provide the most cost-effective and future-proof solution.
The Viessmann Vitocal 300-G heat pump was chosen for its reliability and expected lifespan of at least 20 years, while the system’s six, 200 metre horizontal ground loop arrays are expected to last in the region of 50 years. The Vitocal 300-G also scored highly for its quiet operating noise and high coefficient of performance (COP), of up to 4.8.
As indoor space was at a premium, an existing outbuilding was converted for use as a plant room. Highly insulated runs provide underfloor heating to two floors of the cottage and to radiators in an attic room. The installation has left room for future planned expansion, which includes an outdoor swimming pool.
The installation of the Vitocal 300-G ground source heat pump has had a positive impct on the property’s energy usage, with just 13,642 kWh of electricity used within the first 15 months. This corresponds to 55,932 kWh of heat generated in the same time period. Justin Broadbent from isoenergy says: “Trying to convince a customer to install a heat pump is often a challenge as many don’t believe the energy efficiency predictions can be true. With an annual energy production of 44,745 kWh heat per year, this installation is a great example of how our predictions have been proven, with the heat pump meeting the exact expectations anticipated from a 17.6 kW heat pump.”
In addition to the fuel efficiencies, Grovers Cottage’s owners are also able to save over £2,800 in heating costs over the course of a year in comparison to a gas fired boiler. Justin comments, “To heat the property to the same level as the heat pump with a traditional gas-fired boiler would cost in the region of £4,000 per year, but this Viessmann solution enables the customer to do it for just £1,200”.