Homes on the Isles of Scilly are the least energy efficient in the UK, according to a new study.
Home improvement firm Everest analysed more than 15.6 million home Energy Performance Certificates (EPCs) across the country to find out the best and worst areas for energy efficiency.
Around one million dwellings received the lowest EPC scores of F or G, with inhabitants paying 3.5 times more in energy bills than those with an A or B rated EPC.
The Isles of Scilly, Gwynedd and Ceredigion are the three The Isles of Scilly is the worst local authority area in the UK for EPC scores, with 35% of properties on the islands receiving an F or G.
Nicola Stinson, the Council's Senior Manager for Strategic Development, told This is Scilly that the Authority is currently undertaking a comprehensive review of the condition of its stock.
She said: "This will allow us to prepare an investment plan for the next five years to ensure that our homes continue to meet current standards (including satisfactory EPC levels). This will complement the work completed in partnership with Hitachi on the Smart Energy Islands project, which has seen renewable energy measures installed in many of our social stock.
"We also continue to seek funding for the private sector homes and work in partnership with others including Inclusion Cornwall who are over here discussing fuel poverty/energy efficiency, current projects and the new Warm Homes Discount which they have secured for residents of the Isles of Scilly.
"This could mean up to £500 worth of support to help with heating repairs, loft insulation, home visits, draught excluders and energy efficient lightbulbs to keep people warm and more efficient in their home."
Nicola also pointed out that the least satisfied householders on Scilly are in the private rented sector, with 51% of respondents to the 2015 Housing Survey saying their homes are too costly to run. Meanwhile, the highest spend on fuel bills is among owner occupiers, with 49.9% of respondents spending in excess of £2,600 per year.
London homes are the most energy efficient and have the lowest bills, according to Everest's data.