Case Study

Converted church relies on (super) natural energy

What: A historic 17th Century church has been lovingly restored to give the ancient building a new, energy-efficient lease of life.

How: 8.5kW Kensa High Temperature Single Compact heat pump provides 100 per cent heating and domestic hot water

Result: Underfloor heating system delivers free energy from the grounds with RHI payments an added bonus

This renovated 17th century church in rural Wales may give some the chills, but thanks to modern energy-efficiency measures and a ground source heat pump from UK manufacturer Kensa Heat Pumps, its owners are enjoying low-carbon warmth by harvesting free energy from their grounds, which also attracts seven years of quarterly income through the Renewable Heat Incentive (RHI) as a big treat on the side.

With the support of Kensa Partner Installer, Ground Sun, the property has been converted to a modern, energy-efficient residential dwelling. The rural off-gas location of the site made a ground source heat pump the ideal solution.

Naturally, the church required extensive energy-efficiency improvements to ensure the project’s suitability for a ground source heat pump. Ground Sun worked closely with the architects and the builders on this project, making recommendations about underfloor heating and insulation to ensure the heat pump would work as efficiently as possible and to satisfy the client’s desire for a sustainable, energy- efficient home.

Thanks to the measures installed the heat loss for the building was reduced to c.30W/m2. Typically buildings of this nature prior to fitting modern energy efficiency measures would expect a heat loss of 100-120W/m2 (this would mean the project would have been looking at a 24kW heat pump rather than an 8.5kW High Temperature heat pump!).

Following the energy efficiency improvements a Kensa 8.5kW High Temperature Single Compact heat pump was chosen to provide all the heating and hot water for the 274m2 property.

It was also important to get the heat loss for the building lowered as there was only enough ground to install 3 x 50m long slinky trenches to accommodate the 8.5kW heat pump. The trenches were dug by the builders on the project and filled with a total of 900m of PE32mm slinky pipe.

The MCS accredited renovation qualifies the client for quarterly payments from the Government’s RHI; these payments will continue for a seven-year period. The ground source heat pump is installed in a subterranean plantroom to the rear of the church. As it’s a very wet part of the country it was decided the heat pump should be fitted on an elevated reinforced steel shelf in case of flooding.

Top: The living area of the beautifully restored 17th century church. Middle left and right: Preparing the underfloor insulation. Bottom left: The project began with the digging of a 50m trench for the heat pump