The world's cities are forecast to account for a large proportion of the projected growth in global energy consumption and related carbon emissions. City authorities can ameliorate this impact by taking ownership of local energy practices, working in collaboration with the private sector to deliver solutions. More energy efficiency measures are likely to be welcomed by an increasing number of consumers, as new ways are sought to reduce energy bills and carbon footprints.

Solutions and best practices exist that can lead to more intelligent, cleaner and more efficient energy systems - offering new services and more choice to consumers. Pioneering cities like Boulder in the US, Woking in the UK and Växjö, Sweden, demonstrate that cities are indeed leading the way towards a smarter energy future. A proven technique for the improvement of energy systems is the decentralization of electricity generation, which reduces the energy losses associated with transmission and distribution. Heat that would otherwise be wasted can also be put to better use. Many cities have established district heating which distributes heat by-product to buildings.

Most cities have considerable potential to increase their share of energy production from renewable sources. This may be done by harnessing natural resources such as solar, wind or biomass. The development of distributed, small-scale renewable energy facilities will require robust yet flexible electrical infrastructure. In the future, such infrastructure may need to accommodate a growing fleet of plug-in electric vehicles. SmartGrids - a concept which merges information and communication technologies with electricity networks - provide a plausible technological framework to achieve just this, whilst realizing substantial energy efficiency gains. Manufacturers and electricity companies are beginning to trial SmartGrids in urban areas, often making use of established communications systems. One major problem with many established energy systems is that energy delivered to the end-user is essentially invisible. There is often no way of knowing how much is being used or where it comes from. Smart metering monitors gas, electricity and water supplies and makes available data for manipulation. Smart meters can improve general awareness and understanding, and can create price incentives for consumers.

This set of knowledge cards describes ideas, initiatives and best practice case studies for urban energy systems. It is hoped that these cards will provide a useful stimulus to improve local energy practices in cities across the globe.