An energy-efficient home, by definition, is cheaper to run. This will be attractive to buyers who are looking to slash their bills, and their carbon emissions.
You can often improve the energy efficiency of your property with a few simple changes.
Install insulation in the loft,
the cavity walls, and around the pipework. Removing draughts from around doors and windows and adding double glazing, can be helpful - provided that the planning laws permit these changes.