OLD met new in West Somerset this week, as Dunster Castle became the National Trust's first Grade I listed building to install solar panels to collect renewable energy.

The 24 photo-voltaic panels will provide a significant source of energy to the castle, the equivalent of that used by two ordinary family homes, while also reducing the building's carbon footprint.

Barclays Bank contributed £30,000 of the total £55,000 scheme, while the Low Carbon Buildings Programme, administered by the Energy Saving Trust, gave £15,000 and the National Trust £10,000.

Dunster Castle property manager William Wake said the castle had set itself a three-year goal to reduce its carbon footprint.

"Saving energy, along with reducing water consumption, increasing recycling, promoting green transport and many other initiatives will play a crucial part in this," he said.

"The PV cells themselves will generate 5,500 kilowatt-hours (kWh) a year of electricity, so that we don't have to import that electricity from the fossil-fuelled National Grid. This will save almost 3,000kg of carbon dioxide a year - that's the equivalent of travelling almost 14,000 miles in an average car.

The potential impact of installing solar panels on such an historic building has been considered.

Mr Wake said: "The design has sensitively taken account of aesthetics and the historic importance of the building by ensuring no loading or direct contact of the panels or frame on the roof itself, and that the panels will not be visible from ground level."

Rob Harman, head of sustainability for the National Trust, said: "These PV panels will demonstrate how we can harness renewable energy even from hugely important conservation sites without affecting their special character."