The authors of Sustainable Urban Energy Policy discuss the implications of heat networks and how more sustainable heating provisions can be created.
In November 2015 the UK Government announced a £300m capital fund for heat networks – the largest sum ever allocated to this energy infrastructure in Britain. It was something of a surprise. Many people remain unaware of the technology, the reasons why it is considered worthy of investment, or the fascinating conundrums involved in its deployment.
Most of us in affluent societies give little thought to where the heating for our homes, workplaces, shops, leisure centres, libraries (etc., etc.) comes from, or what its combined social, economic and environmental costs are. In British cities, millions of gas central heating boilers rely on a vast, highly regulated and commercially-operated array of hardware to distribute gas extracted from the North Sea and much further afield. But our future access to reliable gas supplies is uncertain, and even more importantly, the evidence of climate change makes it very clear that we need to stop burning gas, or other fossil fuels, if we are to avoid the major risks of climate disruption.
Our recent book Sustainable Urban Energy Policy: Heat and the city discusses what might be done to create more sustainable heating provisions in cities. It explores the emerging policy thinking and practices, particularly in relation to energy saving and heat networks. Even though the UK has strict Climate Change targets in legislation, policy has only recently begun to broaden its focus beyond electricity to include the future of heating, and progress is patchy. District heating networks are one of the solutions which UK Government regards as a way forward, particularly in densely populated areas.
Heat networks: an introduction for newcomers
District heating is well-known in many European countries where it delivers heat to buildings via highly insulated underground pipe networks. Its value as a sustainable heating source is derived from its adaptability to any available source of heat, which can then be shared among numerous users. Some heat sources which would be too difficult to use in an individual building can supply heat networks. In Islington for example, the council is exploring use of heat from the London Underground, and in Shetland, the Lerwick heat network is planning to use heat from sea water, boosting the temperature with an electric heat pump. By shifting heat production out of buildings to shared facilities, heat networks can also result in better integration across energy systems. Heat is much easier to store than electricity, particularly at large scales, so using electric heat pumps with heat networks can contribute to balancing electricity supply and demand: when the wind is blowing but demand for electricity is low a heat network can absorb the excess, as happens in Denmark today.
Heat networks can, however, be challenging to develop, because these systems create long-term interdependencies between suppliers and users. The insulated pipework is costly to manufacture and install, meaning heat networks are typically considered economically viable only in densely populated areas where a large quantity of heat can be delivered through shorter lengths of pipe. We found a variety of perspectives on when a heat network makes economic sense: for example it makes a big difference if the costs are spread over the estimated forty year life of the network, rather than having to be recovered faster. Perspectives on heat network economics are just one dimension of differences which emerge when individuals and organisations consider proposals. These differences matter hugely to efforts to develop district heating, because of the coordinated action required for investment to proceed. In our book we explore the intertwined social, technical and economic issues involved in constructing heat infrastructures in cities. Main messages from Sustainable Urban Energy Policy: Heat and the city:
Minimising the most severe risks of climate change means ending societal dependence on fossil fuels, and radically improving the efficiency with which we use all energy sources. Such deliberate transformative change is, however, without precedent. Sustainable Urban Energy Policy debates the major…
Paperback – 2015-11-30
Routledge Studies in Energy Policy