District heating can provide cost-effective and low-carbon energy to local populations, such as space heating in winter and year-round hot/cold water: this is also associated with electricity generation in combined-heat-and-power systems. Although this is currently rare in the UK, many legislative policies, including the Renewable Heat Incentive, aim to increase the amount of energy from such sources; including new installations, as well as extending/upgrading existing distributed energy schemes. Sheffield already has an award-winning district energy network, incorporating city-wide heat distribution. This paper aimed to demonstrate the opportunities for expansions to this through geographical information systems software modelling for an in-depth analysis of the heat demands in the city. 'Heat maps' were produced, locating existing and emerging heat sources and sinks. Heat loads (industrial, commercial, educational, health care, council and leisure facilities/complex) total 53 MW, with existing residential areas accounting for similar to 1500 MW and new housing developments potentially adding a further 35 MW in the future. A number of current and emerging heat sources were also discovered - potential suppliers of thermal energy to the above-defined heat sinks. From these, six 'heat zones' where an expansion to the existing network could be possible were identified and the infrastructure planned for each development. (C) 2012 Elsevier Ltd. All rights reserved.