A leading National Trust property – the Trusts largest oil consumer – has won the 2015 Renewable Energy Project of the Year for a 300 kW marine source heat pump project using HFC-134a.
The heat pump replaces the ageing heating system, which was using 128,000 litres of oil each year.
The project was installed at Plas Newydd, a mansion built in the 18th Century and set on the edge of the Menai Strait on the Isle of Anglesey.
The 4×75 kW installation utilizes the tidal currents of the Menai Strait, and is currently operating with a COP (Coefficient of performance) of 4.06 against a design COP of 3.4.
A small amount of sea water, at between 7 and 17 C, is pumped through a network of pipes to and from a heat exchanger on the shore, from which another pipe then takes water up 30 metres of cliff face to the mansions machine room, where the heat pumps further increase the temperature of the water to be fed to the mansions heating system. The HFC-134a heat pump was projected to enable an 80% reduction in carbon emissions as well as providing conservation-grade heat for the historic property.
Source: Carbon Trust and equipment manufacturer.