A new report from Nesta challenges the common belief that homes need extensive insulation before heat pumps can be installed.
Nesta’s analysts argue that while insulation is generally beneficial, it is not essential for switching to heat pumps and that heat pumps can be installed and work efficiently in less well-insulated homes.
The report emphasises that the key factors affecting the efficiency of heat pumps are system design and properly sized radiators, rather than insulation alone. It states that a well-designed heating system with correctly sized heat emitters is the most important factor for a heat pump’s efficiency.
It also mentions that heat pumps can be cheaper to run than gas boilers, especially with the recent decrease in the electricity-to-gas price ratio. It suggests that government action, such as rebalancing electricity levies, could further reduce the running costs of heat pumps.
The report also notes that low-carbon heating can fully eliminate carbon emissions from home heating, while insulation on its own can only reduce emissions. Viewed purely from the perspective of decarbonising, investing in low-carbon heating is an effective way to meet the UK’s climate goals. However, insulation should not be viewed solely in terms of carbon savings..
However, the report acknowledges that insulation brings additional benefits beyond carbon savings, including improved comfort, health, and potential grid flexibility.
While some insulation measures, like draught proofing, loft, and cavity wall insulation, are considered cost-effective, others, particularly solid wall insulation, may be more expensive and not always justifiable in terms of cost.
The report recommends a pragmatic approach to insulating homes in the UK alongside the roll-out of heat pumps. The proposed approach includes the following recommendations:
• Improve 13 million homes to reach EPC C standard by 2030, with an estimated investment of around £60 billion.
• Properties with easy-to-treat cavity wall and loft insulation should be targeted as a priority over hard to treat properties.
• Greater emphasis should be placed on insulating households in fuel poverty, and governments in the UK should aim to insulate fuel-poor households and social housing to a high standard wherever possible.
• There is a strong case for higher standards in private rental properties, and governments in the UK should regulate for minimum standards of insulation.
• This insulation roll out should happen alongside a low-carbon heating roll out, and households should not be discouraged from buying a heat pump if their home is poorly insulated.
Read the report Insulation impact: how much do UK houses really need?
