Defining sustainable energy

The terms sustainability and sustainable energy are constantly referenced in energy policy discussions and the climate change debate. However, there is no single definition of sustainable energy. Instead, there is a wide range of interpretations. This lack of a common framework is at the root of many arguments over the sustainability (or otherwise) of energy technologies or policies. This paper examines possible approaches to defining sustainable energy. It puts forward a working set of principles for assessing the relative sustainability of options for energy supply and use and identifies areas of continuing debate that should be a priority for further attention.