Project: Milestone House
Heating Solution: Strada DBE
Gordon & Lori Rautenbach recently retrofitted their 16th-century listed home in Bramley, Surrey, with renewable energy and heating systems, to create an energy-efficient, sustainable residence. Their vision and achievement resulted in a 'Highly Commended' award in the Domestic Ground Source Heat Pump category at the 2013 National Heat Pump Awards.
Two sixty metre bore holes were drilled in the garden behind the house to create a natural water supply from the aquifer. This water - pumped into the house at 8°C from one of the boreholes - then passes through a drip-tray equipped, heat exchanger (located in the walk in pantry to keep food chilled), and returns the water to the other borehole at 4°C. The Danfoss ground-source heat pump, which extracts 4°C of the water temperature, and (with its compressor) boosts it up to the higher temperatures as needed for the hot water and central heating via the Jaga dynamic radiators. A 4kW ground mounted photovoltaic system provides some of the electricity needed to drive the pumps and compressor.
To support their self-sustainable strategy, 21 Jaga Strada DBE radiators were installed throughout the property for heat pump compatible, energy-efficient heating.
The Strada DBE radiators, which feature Jagas Dynamic Boost Effect technology to provide an instant boost of heat when required, were selected by Gordon primarily for their extremely quiet fan noise. Reaching less than 35 dB(A) when on boost mode, the DBE unit fans are quieter than a domestic refrigerator. "This was absolutely imperative. While we wanted the heat boosting technology, it just wouldn't have worked in such a quiet domestic situation if the fan noise was at all noticeable."
Cementing Gordon and Loris decision to choose Jaga as their radiator manufacturer was the Strada DBE's compact and unobtrusive design. The Strada radiators were ideal for blending with the interior decor, said Gordon. While we wanted energy-efficient heating that was compatible with our heat pumps, it was vitally important to us that the radiators provided a simple and elegant aesthetic that would not dominate our living environment. We also appreciate quality for its own sake as well as providing long term value for money.
Milestone is also equipped with a ducted heat recovery system as well as effective insulation. This, in conjunction with Jaga's low-temperature radiators, means there is little heat loss during night cooling. "Because the Strada radiators are low-temperature units, their low mass makes them highly responsive and precisely controllable," explained Gordon. "Turning a heating system on and off uses a lot more energy than people think when they are part of a heat pump system, so we have a large buffer tank, and we were adamant we wanted solutions and products that didn't require this level of attention."