One of Dorset's oldest historic buildings, Athelhampton House, has been given permission to make use of the most modern energy technology.

Dorset Council has previously given permission for the grade I listed site to be fitted with ground source heating and solar panels – but air source heating will now be used for the main house after improvements in efficiency from a new design.

The application for the 15 units alongside the stables and the house attracted no negative comments and was supported by the Dorset Gardens Trust which said: "The applicant is to be commended for changing his proposals in the light of emerging technology. The use of air source heat pumps … is entirely acceptable and welcome".

A statement from planning agents says the net reduction in carbon because of the combined projects is expected to be more than 100 tonnes annually and could be more if the air source heat pumps prove to be as efficient as promised.

The new heating method will allow the house to add rooms to an underfloor heating scheme, mostly to the upper floors in the North Wing as well as some in the East Wing.

When the estate changed hands in 2019 the new owner, Giles Keating, was keen to reduce the use of LPG gas and oil as a source of heating and fuel to the house, Coach House and kitchens.

The first house on the site is believed to have been started in 1493 during the reign of Henry VII by Sir William Martyn, then Lord Mayor of London with the West Wing added about 1550.

Athelhampton claims several Thomas Hardy links with the author making a watercolour of the view in 1859 which is today owned by Dorset Museum. Hardy also mentioned Athelhall in his story The Waiting Supper which was published in 1888. It also features in some of his poems.

The late Robert Cooke bought the house in 1961, shortly afterwards opening it to the public. The last member of the Cooke family to own the house, Patrick, sold the property in 2019 to Mr Keating.

The planning permission also includes the removal of a lift in the north east of the building which was put in by the Cooke family and the installation of a stairway in its place.