The National Trust’s most polluting property is going green. Once heated by an oil boiler, Plas Newydd, located on Anglesey, is now to be heated by the Menai Straits. During the winter months, the house used to use 1,500 litres of oil a day, which is the same amount an average house would use in 10 months. Now after a £600,000 revamp, water is pumped from the straits through a 53 meter pipe into a heat exchanger which works in a similar way to a refrigerator only in reverse. Heat is extracted from the seemingly freezing water using the same chemical that a refrigerator uses, and rather than the extracted heat being a waste product, it is used to heat water. This warm water is then pumped around the 18th Century house providing all of the hot water and heating. The scheme is the largest of its kind in the UK and was developed with the help of scientists from Bangor University’s School of Ocean Science and conservation experts to ensure the fragile environment of the straits was protected. The project is expected to save the trust £40,000 a year in running costs, and stops them having to store 15,000 litres of oil on the banks of the Menai Straits.