Second phase of ground source installations bring big savings

Public Sector Mon, Jun 13, 2016 8:46 AM

In 2015, Bromford Group commissioned Kensa Heat Pumps to install ground source heat pumps into 16 formerly electrically heated bungalows in rural Shropshire.

Intended as a pilot scheme to determine the viability of the technology, the ground source heat pumps proved so successful at reducing resident’s fuel bills and providing a reliable heat source that in 2016 Bromford decided to commission a second project with Kensa Heat Pumps.

The second phase is proving to be just as successful, with residents at one site already experiencing a £15/week saving on their fuel bills with ground source heat pumps compared to their old heating system, which is a significant saving to those living in fuel poverty.

The project comprised 20 properties spread across two locations in Didmarton and Bibury in Gloucestershire. The properties were a mixture of semi-detached and terraced two bed bungalows housing elderly and disabled residents. The properties were previously heated by old electric night storage heaters, but dissatisfied residents said that they were expensive to run, inefficient and difficult to control. Bromford decided that the residents would benefit from the lower running costs and increased comfort delivered by a ground source heating system.

The positioning of the clusters of properties made the project perfect for utilising Kensa’s innovative micro district heat network system featuring a communal borehole network with an individual ground source heat pump installed in every home. A single borehole drilled to a depth of 110m deep, provides each per pair of dwellings with a sustainable heat source. An experienced drilling company carried out the work and took care to keep any noise and disruption to a minimum.

This innovative ground array infrastructure meant that the project was eligible for the Non Domestic RHI scheme. Payments are based on the metered output of the heat pumps, which for this site equated to an average of £354 per property for the first quarter of operation from February-April 2016. Non Domestic RHI payments are made quarterly over a twenty year period to offset the cost of the investment and provide a lucrative income stream. Kensa also negotiated an upfront ECO grant to support the investment work through a unique partnership with EDF Energy.

Kensa installed 6kW Shoebox Twin ground source heat pumps into the properties. Small and compact, these heat pump models fit neatly and easily inside the resident’s airing cupboards to provide 100% of their heating and hot water needs. In addition to this, new radiator systems and hot water cylinders were installed to replace the night storage heaters, along with thermostatic heating controls enabling residents to have better control over their heating.

The installation wasn’t without its challenges; weather during January and February was very wet, which meant that the drillers had to carry out extra ground protection. Also, surveys revealed the presence of asbestos at the Didmarton site, which required specially trained operatives to advise on the relevant health and safety procedures to be followed during the installation of the radiators and heat pump units. Nonetheless, the installation works were completed on time to a tight schedule, with work beginning in January and completed in March.

Matt Trewhella, Contract Manager at Kensa Heat Pumps said: “We were pleased to continue our ongoing partnership with Bromford with this project in Didmarton and Bibury. By replacing old, inefficient electric heaters with new, sustainable ground source heat pumps, we are helping them to make a difference to their residents, saving them money and improving their wellbeing.

“This was an interesting project due to it being based over two different sites, featuring challenging drilling conditions and having a tight deadline, but we are very pleased with the outcomes. Kensa is in the process of starting a third phase of ground source heat network retrofits with Bromford, which will be progressing over the spring, again replacing electric heating.”