Heat pump retrofit in London

Decarbonising heat is one of London’s biggest challenges to achieving net zero emissions. Natural gas, used mainly for heating buildings and water, accounts for 37 per cent of all greenhouse gas emissions in London.

To achieve the Mayor’s net zero target by 2030, London will need to make a rapid transition from gas to low carbon heating solutions, the majority of which will be retrofitted into existing buildings, since at least 80 per cent of our buildings are expected to still be standing in 2050.

The Mayor of London, Sadiq Khan, commissioned the Carbon Trust, to produce these two reports which explore what a heat pump retrofit actually means on a building level and the kinds of policy and support mechanisms that will be needed to drive individuals to switch their buildings to low carbon heating systems.

This main report shows how heat pumps will have a critical role in tackling emissions from London’s buildings and provides an action plan for scaling up energy efficiency and heat pump retrofit across the capital. It is intended to help guide local authorities, social housing providers and others considering a heat pump retrofit, and highlights the principles of good practice system design.

The accompanying case studies report provides a detailed analysis of the potential to retrofit heat pumps in 15 existing buildings in London, outlining the accompanying energy efficiency retrofit measures that are required and the potential carbon savings and costs.

The reports show that whilst further financial support or incentives will be required for most building types to transition to low carbon heating solutions, some building types already have a strong financial case and should be prioritised for retrofit and energy efficiency investment. These include electrically heated blocks of flats and buildings that are due for major upgrades to the building fabric or heating system.