Sea Change in Charity’s Energy Policy

You’re responsible for a historic building, and you’re finding the heating bills an increasing burden? There’s a fairly simple answer - so long as you live near the sea, that is.

Plas Newydd, an 18th-century mansion on the coast of North Wales, is switching to renewable energy supplied by an inexhaustible source – the waters of the Irish Sea, fed by the vast amounts of energy generated by the Atlantic Ocean.

The house is in the care of the National Trust, the charity responsible for the care of historic houses and countryside across England, Wales and Northern Ireland (a separate body does the work in Scotland).

Plas Newydd, which means “new house” in Welsh, was formerly the Trust’s biggest oil consumer. In winter months, it sometimes burned around 1,500 litres of oil a day – as much as a typical house would use in 10 months.

Now it is to be heated by an energy system that pumps a small amount of sea water from the Menai Strait, between the Isle of Anglesey – on which Plas Newydd stands - and the Welsh mainland, through pipes to and from a heat exchanger on the shore, and then 30 metres up the cliff face to the mansion’s boiler house.

The system uses a 300kW marine source heat pump – one of the first in the UK – and cost £600,000 ($1,012,410) to install.  But it is expected to save the Trust around £40,000 ($67,500) a year in operating costs (ROI 15 years).  It will provide all the power needed to heat the house, including a cricket pavilion on the estate.

Sea Change in Charity’s Energy Policy