Introduction to Our Eco House – Part 1 – Ground Source Heat Pump

After several months designing and building our eco home, we’re starting to see some real progress.

We decided that an old poorly insulation bungalow in Purleigh near Maldon in Essex would be a great opportunity to demonstrate all the services/product we provide in one place. The original bungalow was demolished, leaving only the foundations. These foundations were extended to form the base of our new building.

Ground Source Heat Pump Trenches It was decided that a ground source heat pump installation would suit the house best. The reason for this is that the building will be well insulated, underfloor heating will be fitted and the garden is large. Firstly we dug trenches 1.2 metres deep in the garden and laid our pipework. We decided to opt for a horizontal array, but if you’re tight for space or don’t want to dig your garden, then a borehole may suit you better.

For more information on our ground source heat pump installations visit the ground source heat pump section of our site

The heat pump used is a Vaillant 6kW Geotherm, this is able to generate approximately 4kW to heat the house for every 1kW used.

We then constructed a small shed to house the heat pump itself and a buffer tank. These can be located within the house, but as we have a large garden we decided to save space in the house. The ground source heat pump is a great way of using the natural warmth of the ground (which doesn’t fall below 5⁰C even during winter) to heat your home. The set-up will also provide a large part of the hot water requirements. The heat pump can provide 100% of the required hot water, but we’re also installing solar thermal.

Ground Source Heat PumpThe ground source heat pump is eligible for the Renewable Heat Premium Payment, which provided a £1,250 payment from the government after installation. Also, starting next spring we’ll be able to claim for the Renewable Heating Incentive, which will pay out for each unit of heat generated.

To heat the house itself the underfloor heating system draws heat from the buffer tank and pumps this around its network. Unlike traditional heating systems the ground source heat pump is most efficient when operated at a fixed temperature, i.e. the house’s temperature is maintained throughout day and night. This creates a very comfortable environment within the house, which is no longer subject to fluctuating temperatures.

Underfloor HeatingThe heat pump was installed several months ago and was able to comfortably warm the house despite the exceptionally cold and prolonged winter. We’ve also notice a very significant saving when compared with the old oil based heating system used previously.