Ground Source Heat Pump

A complete home energy make-over

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This is a video article of an interview with Gary Jack, a householder living in the The Pentland Hills, an area immediately south of Edinburgh.

Gary has approximately an acre of garden around his house.  He has undertaken many home energy improvements to his property including fully insulating the walls and roof space of his house, installing a 6 kW wind turbine and putting in a ground source heat pump and thermal store.  At the time of the interview he was also about to install a ground-mounted array of solar PV.  

We interviewed Gary in August 2011 about the work he's done, how it all fits together and the impact it's had on living in his home.


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How important are financial incentives to householders?

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As the Renewable Heat Premium Payment opens for business, GEN speaks to three homeowners in different settings about their renewables projects and the role that financial incentives have played.

Urban eco-family going solar

Daniel lives with his partner and two children in a 150 year old terraced house in Leith, Edinburgh. One year ago they decided to install a 1.58kW solar PV panel on their roof. As Daniel explains it was the natural next step in a carbon saving  journey, “We read an article by Mark Lynas about carbon footprinting in the home and had really done everything that can be easily done to an older house. The gas boiler had been switched to an efficient condensing version, alongside draftproofing and changing all the bulbs to energy efficient versions and installing a wood stove. We had a bit of money put aside so with the Feed-in–Tariff coming in alongside a grant we went ahead with solar PV.”

The installation cost approximately £9k with around 30% of the cost being paid through an Energy Saving Trust grant. Daniel says the FiT was an attractive part of the package. “It seems like an ideal way to invest savings when there is a guaranteed return for 25 years at such a good rate.” He admits though that the FiT is more attractive if you don’t intend to move away. “We live in a nice place with the kids settled at the local school, the solar installation was part of improving the house on a number of levels. I hope to enjoying the financial benefits of lower cost bills in this house well into my 70’s.“

In terms of advice they went to the Energy Saving Scotland advice centre, who helped set up the grant and put them in touch with suppliers. 

Rural family swapping oil for a renewables mix

Living in Fintry, Stirlingshire presents some energy challenges for Gordon and his wife and two children. Being off the gas grid and running an old inefficient oil boiler was expensive for a four bedroom older house so renewables options were investigated. The first project was to install a 1x2m solar thermal panel on the roof about 4-5 years ago. ‘It provides about half of our hot water needs and there is virtually no maintenance needed’ says Gordon. The cost of installation was around £3k and at the time an SCHRI (Scottish Communities & Householders Renewables Incentive) grant brought the cost down by a further £1K.

The biggest project though was to replace the oil boiler. The options were narrowed down to a biomass boiler or a ground source heat pump (GSHP). Gordon explains, “We wanted a mix of cost savings and functionality, the ground source heat pump fitted the space we had available a lot better but it had to be able to heat the existing radiators properly too.” They ended up with a 17 kW GSHP sunk into a borehole in the garden. Total installation costs were about £17k with £3k covered through a grant and £10k of the capital outlay being covered by an Energy Savings Trust loan.

“The loan made a huge difference to the project going ahead, I think that even when the RHI (Renewable Heat Incentive) comes in people will still need a way to cover the upfront capital otherwise the scheme will just benefit those who have substantial savings to put into projects.”

The GSHP was installed last December during the coldest part of an exceptionally cold winter. So far the family have had a noticably warmer house with lower fuel bills with estimates that the GSHP will save between £500-1,000 per year. Advice and information was was gathered from a range of sources including an energy advisor employed by the Fintry Development Trust who pay for his work from having a financial stake in the local wind farm.

Renewable central heating for an off-gas terrace

Mark and Melinda live with two young children in a three bed room terraced house near Doune in Stirlingshire. Four years ago they moved into their property which is off the gas-grid and required some modernisation. They explain, “We had very little time to do the property up before moving in, but were keen to replace the ancient electric storage heaters with a proper radiator based central heating system that was renewable and cheaper to run than an oil boiler.“ In the end the family chose a 13kW stove that runs on biomass woodfuel pellets. “We didn’t have enough space to house a full scale biomass boiler, but the pellet stove option seemed like a good idea as it could fit in the living room while the pellets are stored in bags in the garden shed.”

The cost of the whole central heating re-fit was around £7k with the family receiving around £900 through the SCHRI to help with capital costs. Total fuel costs for heating and hot water from the system come in at around £1k a year. Did the grant make a difference? Mark explains, “It was certainly helpful at the time, but we had made some profit from the sale of our last house, so we put most of it into doing the new house up including the installation of the central heating system. If we were to do it again now, then getting a low cost loan would be essential. I have seen the new RHPP rates (Renewable Heat Premium Payment) but they look pretty similar to what we got under the old grants.” Advice came from contacts who had installed similar systems and from suppliers.

Loans are key

It clearly depends on the circumstances of the householder but incentives have a role to play in terms of promoting the options available and in 'nudging' consumers down the renewables path. Given the ongoing slump in house prices and the reluctance of banks to lend, the amount of capital available to make a green switch is going to be limited in the medium term.

Government's would be well advised to consider how loan funding can work alongside other initiatives such as the Green Deal to overcome this barrier, while keeping the rules around incentives such as the Feed-in-Tariff stable.