The Sutton Decentralised Energy Network

Sutton Decentralised Energy Network (SDEN) is a truly ground-breaking initiative to use heat, to deliver low-carbon supplies of hot water for heating and domestic use across South London.

We have the potential to deliver heat to 19,000 new homes. We’re already working on Phase 1 of our network which will be capable of supplying 3.3 GWh of heat to around 725 homes and a supermarket at the new Felnex development.

That will save 900 tonnes of CO2 emissions with future phases expected to increase this to over 5,000 tonnes.

You can access the official SDEN website here.

Developers – how to get involved

We are looking to expand the network across Sutton and into Croydon and Merton. If you are a developer interested in finding out more then call us on 020 8770 5918 or email

Developers can read the full SDEN Prospectus [PDF, 873 kB].

We are exploring connections to existing sites, including St. Helier Hospital and Carshalton College, as well as residential developments.

The boroughs of Croydon and Merton are also working with us to expand the network across South London. Homes on the Felnex Estate could be using SDEN as early as spring 2017.

“SDEN offers developers an alternative to using fossil fuels. By harnessing heat from the Energy Recovery Facility in Beddington, we can channel it into homes and premises in south London to provide low carbon energy. We want to help create a better environment for everyone and any income generated will be reinvested back into local services.”

Councillor Ruth Dombey, Leader, London Borough of Sutton

SDEN – Benefits to the community

  • Low-carbon content – By reducing carbon emissions, we are creating a more sustainable environment, helping Sutton achieve its One Planet Living goals.
  • Profits invested into services – Any profits we make from the SDEN will be put into services for our residents and businesses
  • Resilient supplies – Customers will never need to worry about their boilers breaking down, because they won’t have them.
  • Price parity – We will benchmark our prices against the cost which would be paid using natural gas boilers.
  • No green premium – Our extremely green supplies come at no additional cost.
  • Employment – Building and operating the network will create at least 20 new jobs.
  • Integrating other heat sources – We have the opportunity to harness heat from other businesses, helping them to lower their carbon footprint.

SDEN – Benefits for developers

  • Reductions in construction costs.
  • Increased floor area available for letting.
  • Enables developers to meet planning regulations more easily.
  • Reduced exposure to green taxes & levies.
  • Avoids ongoing heating plant maintenance.
  • Better resilience than commercial suppliers.
  • Participation in an innovative scheme that will deliver significant carbon savings.

SDEN: How it works

SDEN will use energy generated by our new Energy Recovery Facility to provide low-carbon heating and hot water to homes and businesses in Sutton and neighbouring boroughs.

It also has the potential to harness energy from other businesses.

The majority of other decentralised energy networks across the UK use fossil fuels in high-efficiency energy generation plants to generate heat. We are different because we would be using low carbon heat so we are truly sustainable: Environmentally, socially, and economically.

This heat will be delivered as hot water, which can be used to meet the heating and hot water requirements.

We will be laying a network of highly insulated steel pipes to deliver the hot water to our customers.

This system will ensure there are minimal energy losses in our network and the pipes will be buried in the ground at a depth of approximately one metre. The pipes will have a lifespan of over 50 years.

The amount of heat energy taken from our network is controlled by users – exactly the same as heating or hot water system fed from a boiler located in the building.

Inside the property, the method used to deliver heating can remain the same whether it’s radiators or under floor heating.

The network also offers better resilience compared to conventional heat supplies. When the low-carbon sources of heat are occasionally offline for maintenance, supplies of hot water will be maintained from our backup and top-up boilers.

We will be installing thermal stores around the network to ensure that we can use as much of the low-carbon heat as possible when these sources are offline.

For more information, please visit our FAQs page.