ONE of the country’s grandest stately homes has unveiled a plan to cut the cost of heating the property, increase its green credentials and stop its art collection of global importance from being ruined. 

Castle Howard, which in 2010 was said to be facing an estimated bill of £24 million to conserve the 10,000-acre North Yorkshire estate’s listed buildings alone, has lodged an application with Ryedale District Council to expand its Great Lake sourced power system and add an array in the Dairy Pond.

The estate has said there is a pressing need to cut its annual operational costs of around £7 million and the income it is able to raise from its various trading operations, such as welcoming 200,000 visitors a year, is insufficient to meet its day-to-day expenses.

The heating system overhaul comes 11 years after the Howard family, which has owned the 145-room grade I listed property for three centuries, sought to reduce vast heating bills and their reliance on fossil fuels by making Castle Howard one of the first historic properties to use renewable technology. 

The initiative saw a lake source heat pump installed to serve 200kW of power to the property, and later, a wood chop biomass system to serve the estate’s office and flats.

Energy experts say, if carefully managed, 200kW would be sufficient to heat scores of modern homes.

Documents submitted to the council state the current heat pump system to the house provides heating to the East Wing, Caretaker’s Flat and some spaces in the West Wing and South Front, as well as hot water to the kitchens which serve the large and award-winning Fitzroy Restaurant.

However, investigations have concluded the 200kW system is not sufficiently sized to cope with the heating and hot water needs of the building, and the family want to increase wet heating provision to areas currently heated by electric oil filled radiators.

The application states the oil radiators “are both costly to run and introduce humidity into spaces with contain precious contents and collections”.

High humidity can harm artwork by making materials swell, cause fabrics to fade, encourage pests and cause mold and mildew growth.

In 2015, a small fraction of the late 17th and early 18th century stately home’s antiques and paintings sold for £12 million at Sotheby’s to help secure the “long-term future” of the estate.

The current owners’ ancestors collected an array of pictures, tapestries and sculpture during the 18th and 19th centuries, including artworks by Canaletto, Sir Joshua Reynolds and Thomas Gainsborough as well as numerous Italian Old Masters.

A spokesman for the stately home said: “The proposed works associated with expanding the existing lake source heating system to Castle Howard will enable the estate to continue its commitment to reducing its reliance on fossil fuels whilst also contributing to providing more stable and suitable conditions for its contents and collections.”

He added the heritage impact of the proposed works had been assessed as low-moderate and would be undertaken under a watching brief and any archaeological features unearthed during the works would be preserved by record.