Heat pumps are vital for decarbonising London’s energy sector

According to a new report, decarbonising the energy sector with mass deployment of heat pumps is critical to London achieving net zero emission targets

Decarbonising heat is seen as London’s biggest challenge to achieving net zero emissions, and heat pump systems may provide the answer.

In ‘Heat pump retrofit in London’, a new report from the Carbon Trust, heat pumps are shown to play a critical role in tackling emissions from London’s buildings and delivering the Mayor’s 2030 net zero ambitions.

Natural gas, used mainly for heating buildings and water, accounts for 37% 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 heat solutions, the majority of which will be retrofitted into existing buildings, as at least 80% of buildings are expected to still be standing in 2050.

However, heat pumps are not a like-for-like replacement for gas boilers and good practice system design will be essential to their effective deployment.

The report, commissioned by the Mayor of London, provides a detailed analysis of the potential to retrofit heat pumps across a range of existing buildings in London. It lays out an action plan for scaling up energy efficiency and heat pump retrofit across the capital.

The report assesses the particular challenges and opportunities for heat pump retrofit in London. It will also help guide local authorities, social housing providers and others considering a heat pump retrofit, highlighting the principles of good practice system design.

Shirley Rodrigues, Deputy Mayor for Environment and Energy, said: “Retrofitting heat pumps and improving the energy efficiency of existing buildings are key to achieving the Mayor’s ambitious target for London to reach net zero carbon by 2030.

“Not only will retrofitting heat pumps help support jobs and skills vital to a green, fair and prosperous COVID-recovery, they also reduce energy bills if designed well. However, delivering this at the scale needed will require the Government to step up investment and implement strong supportive policies.”

Carbon emission savings of 70%

Heat pump systems have the potential to deliver immediate carbon emission savings of 60-70% compared to conventional electric heating and 55-65% when compared to an efficient gas boiler.

In the following decades as the grid continues to decarbonise, these carbon savings are expected to increase to 90-100% of carbon emissions by 2050.

Building occupants will be able to flex their heat demand in response to tariff price signals and other payments for demand with heat pumps. The report finds that engaging in demand side response and flexibility markets is hugely beneficial to the financial case for heat pump retrofit.

The report concludes that most building types will require further financial support to transition from gas boilers. However, some building types, such as electrically heated blocks of flats and buildings that are due for major upgrades to the building fabric or heating systems, already have strong financial cases for heat pumps, and should be prioritised for retrofit.

Tom Delay, Chief Executive of the Carbon Trust, commented: “Buildings and heat have been identified by the Committee on Climate Change as key challenge areas for decarbonisation in the coming decades, and so the analysis and recommendations detailed in the report to promote low carbon solutions that are available now is very timely.

“As always, heat pumps are not a silver bullet solution, which is why we have provided a suite of policy recommendations, including investment in energy efficiency in buildings and flexibility in the energy system.”