• DESNZ and AECOM-developed trailblazing scheme could save buildings in Westminster – including Houses of Parliament and National Gallery – 92% of CO2 emissions compared to current levels
• Heating will be sourced from waste heat generated by the River Thames, London Underground and sewers
• One of AECOM’s biggest and most ambitious undertakings in clean heat for buildings
• Scheme reaches major milestone with appointment of Hemiko and Vital Energi joint venture to invest in and deliver the network

LONDON (6 November 2024) — Plans have been unveiled today for the UK’s largest heat network, which will supply buildings in Westminster with low-carbon heat using waste heat sources such as the River Thames, London Underground and sewer networks. The South Westminster Area Network (SWAN) was developed by DESNZ and AECOM, the world’s trusted infrastructure consulting firm, and could supply decarbonised heat to around 1,000 buildings such as iconic London landmarks like the Houses of Parliament and the National Gallery.

Buildings in the area served by the heat network could save 92 per cent of CO₂ emissions compared to current levels and, by 2040, the scheme could help save Westminster 75,000 tonnes of CO₂ each year, which is the equivalent to 1.2 million trees. DESNZ and AECOM have worked together to plan, design and procure a delivery partner to bring the project to life, working alongside Westminster City Council and other key stakeholders.

The project has now reached a major milestone with the appointment of a Hemiko and Vital Energi joint venture, known as the SWAN Partnership, to invest in and deliver the heat network. The scheme forms one of the UK’s first heat network zones – an area identified for accelerated investment into heat networks – and has the potential to stretch from Victoria Station up to Temple Underground Station near the Strand, bounded by St James’ Park and the River Thames.  

Hemiko and Vital Energi are leading players in the heat network market and will develop multiple clusters of heat networks in the zone. Over time, the heat networks will grow and interconnect with one another to become one very large central London heat network. It is expected that the first heat will be provided in 2026, with the network due to be entirely connected and complete by 2050. This will help buildings in the area to achieve net zero carbon.

The scale and complexity of the project makes it the most significant heat network scheme designed in the UK.

Channa Karunaratne, head of heat networks at AECOM, said: “Heat networks are crucial to the UK’s energy transition. We need to move away from fossil fuels, work towards energy independence and enable growth in our buildings and places, and heat networks are a vital part of the solution. They will not only help the UK reach its 2050 net zero target, providing homes and businesses with low-carbon heat but also provide other vital benefits like improved air quality to our communities.

“The size and ambition of SWAN demonstrate how to drive decarbonisation at a city-scale, and it is a trailblazer for how our cities can operate more sustainability. Westminster is one of the most recognisable locations in the world and through SWAN, the political engine of the UK is going to be supplied almost entirely with low-carbon heat for the first time.

“Since SWAN’s inception, we’ve worked in partnership with DESNZ to commercialise the scheme and accelerate private investment. Reaching today’s milestone with the appointment of Hemiko and Vital Energi is a proud moment for our team and an important step forward for this ambitious project that is helping to secure a low-carbon future for London.”

Minister for Energy Consumers, Miatta Fahnbulleh said: “Taking waste heat from the River Thames and London Underground to heat such iconic places as the Houses of Parliament and the National Portrait Gallery is a really exciting example of what lies ahead on our journey to low-cost, low-carbon heating.

“This project will help support hundreds of jobs and make bold new strides towards boosting our energy security, as one of seven heat network zones we’re backing with over £5million funding.”

Toby Heysham, CEO of Hemiko and spokesperson for SWAN said: “Using heat from the iconic River Thames and London Underground to heat some of the capital’s most famous buildings is a true story of pro-growth circular economy in London.  

“Heat networks are the next big utility in the UK, and we are investing £1bn over the next 6 years into networks that will allow local people and businesses to make use of locally wasted heat. We strive to embed ourselves in the local community, understanding the pressures and opportunities in the area, and figuring out how we can help, such as bringing high-quality green jobs and supply chain opportunities. 

“This network will be the flagship network in the UK, the first new zonal scale network in a market that offers an investment potential the size of the UK offshore wind industry. Steps like this show that the UK heat networks market is open for business.” 

Heat networks supply heat from a central source and deliver it to a number of buildings via a network of underground pipes. Decentralised energy schemes, such as heat networks, are increasingly seen as a vital part of a sustainable energy mix for the UK. At the moment, just 3% of the UK’s heat demand is met by heat networks – but the government plans to increase this to at least 19%, in line with the Climate Change Committee’s recommendations.

AECOM’s work has been supported by HermeticaBlack, specialists in the investment, development and asset management of net zero projects, and specialist infrastructure financial advisory firm Asteros Advisers.

About AECOM 

AECOM is the world’s trusted infrastructure consulting firm, delivering professional services throughout the project lifecycle – from advisory, planning, design and engineering to program and construction management. On projects spanning transportation, buildings, water, new energy, and the environment, our public- and private-sector clients trust us to solve their most complex challenges. Our teams are driven by a common purpose to deliver a better world through our unrivaled technical and digital expertise, a culture of equity, diversity and inclusion, and a commitment to environmental, social and governance priorities. AECOM is a Fortune 500 firm and its Professional Services business had revenue of $14.4 billion in fiscal year 2023. See how we are delivering sustainable legacies for generations to come at aecom.com and @AECOM.