An English Housing Association has demonstrated its commitment to reducing tenants’ energy bills by using the Passivhaus approach in its latest development of 20 homes in South Devon, and has specified bespoke solar cylinders from McDonald Engineers to supply the hot water.
The Passivhaus approach is focused on delivering the ultimate solution in energy efficiency by building homes which minimize the heating demand of the building and provide excellent thermal performance, exceptional air tightness and mechanical ventilation.
A core aspect of any Passivhaus project is the efficiency of the hot water system and so Teign Housing called upon McDonald Engineers to deliver the optimum solution.
McDonald Engineers designed a hot water solution featuring 3 different sizes of cylinders to suit the properties in the development, each with Integron, high efficiency, finned solar coils to maximise the transfer of solar thermal energy to the hot water system.
The cylinders also featured 100mm of high density polyurethane foam lagging, twice the amount usually applied to cylinders to achieve Part L of the Building Standards, in order to dramatically reduce the heat loss from the cylinder.
McDonald Engineers’ Sales Director, Jamie Stewart, commented; “As the most efficient material for hot water solutions, copper is the natural fit for Passivhaus, where energy transfer and heat loss simply cannot be compromised.”
He continued, “With our expertise in designing the optimum cylinder specification to minimize the life time costs of the hot water solution, we are able to incorporate critical changes such as the length of coil, the position of connection and probe pockets, insulation levels and back up immersion heaters.”
With the ever increasing pressure on housing associations and local authorities to reduce their carbon footprint, studies have shown the Passivhaus approach can reduce annual fuel costs by a factor of 5-10 and quote a typical household in 70m2 passivhaus could spend as little as £25 per annum on space heating.