Heat pump installation has novel ground collector
Dimplex ground-source heat pumps have been installed in a new £8.2 million hospital unit for Norfolk & Waveney Mental Health Foundation Trust to help meet low carbon emission targets. They provide heating for Hellesdon Hospital’s ward-winning psychiatric intensive care and low secure units.
The system was developed by Econic, a Dimplex heat-pump installer partner. It uses two 50 kW heat pumps to draw heat from the ground using one of the largest ground collectors of its type in the UK to date. Grants of up to 50% are available for such projects under Phase 2 of the Low Carbon Buildings Programme, amounting to £142 000 for this project.
The design of the ground collector system took into the geology under the site, the heat available from the ground and the annual heat-load profile of the new building.
The collectors were installed using hydraulic pushing technology, with a 33 t 8x8-wheel truck carrying hydraulic rams pushing a steel casing into the ground, into which the collector pipes were inserted. The steel casing was then withdrawn, leaving the pipes in the ground. A total of 120 collectors were installed, each 25 m deep. They are expected to produce about 75 kW of heat.
Other energy saving measures in the building include high levels of insulation, low-energy high-frequency lighting with automatic controls and harvested rainwater for WCs.
