Solar panels are to be installed at Abergavenny Castle Museum.
The historic Grade II-listed building, which is operated by Monmouthshire County Council’s Mon Life leisure service, will also be fitted with air source heat pumps.
The application for listed building consent, also covers the replacement of two air conditioning units, and the work has been advised following a energy audit in September.
The solar panels will be installed on a false beam roof above slates on the south east roof of the castle’s keep.
The beam is to be raised to avoid shadow on the panels caused by the parapet.
Monmouthshire council’s planning department approved the application for listed building consent.
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