Patience brings London district heating rewards

The news that homes on five local authority estates in south London are receive heating energy from a new source looks routine enough at first glance but, to long-term followers of the UK CHP and district energy scene, the story has a particularly satisfying ring to it.

Back in 1986, representatives of three south London boroughs, each worrying about the scarcity and environmental problems of landfilling their waste, got together to seek an alternative. Six years later the consortium, now named South East London Combined Heat and Power (SELCHP), opened a shiny new waste-to-energy plant on a site bounded by railway lines not far from London Bridge station. The 35 MW facility treats more than 400,000 tonnes of waste each year.

But the plant whose very name includes the initials ‘CHP’ generated no heat, only power for export to the grid, as the consortium could not find an economically viable way to connect it to suitable local heat loads. Nevertheless, the plant was built in a way that, should such a load be identified in the future, that heat offtake equipment could be added without too much difficulty or expense. 

Now, nearly 20 years after the plant was first opened, that’s just what is happening. Operator of the plant Veolia Environmental Services and one of the three local government participants – Southwark Council – are working to install a 5 km pipe system to connect the plant to five housing estates in nearby Rotherhithe. The main SELCHP plant is being modified to draw additional steam to feed the new district heating connection. Existing gas-fired boilers at the five estates will be switched off and tenants will be supplied with heating and hot water from a purely refuse-fuelled facility from this October. SELCHP will be a CHP plant for the first time – and a carbon-neutral, fossil-free facility.

London’s Mayor, Boris Johnson, is among those congratulating the consortium on finally realising the full potential of the SELCHP facility, and Veolia says it is talking potential customers to take up the full capacity for heat production from the facility.

Mayor Johnson is an enthusiast for district energy and has set a target to deliver a quarter of London’s energy through decentralized energy by 2025. Indeed several studies are underway into developing new district energy systems in the city that has many high-density heating loads – including one that is investigating taking heat from an existing gas-fired power station on the north bank of the River Thames. Let’s hope that this move in Southwark represents part of a larger movement towards decentralized energy supplies.

While congratulating SELCHP on this latest move, we should also recognise the foresight of those involved in building a heat-ready plant back in the 1990s – and their patience.

Source: COSPP