The most important groups of fuels are fossil fuels, bio-fuels, hydrogen and nuclear fuel (uranium). Of these fuels, only bio-fuels and hydrogen are strictly renewable, but in both cases, this really depends on the energy source used to produce it. We have traditionally been heavily dependent on fossil fuels (first coal, then oil and now natural gas) and more recently on nuclear power. In the future, we will need a more sustainable range of fuels for all potential uses. New technologies such as fuel cells may require a wider range of fuels (e.g. hydrogen) and widen the range of applications for which fuels may be used (e.g. methanol-fuelled fuel cells to power laptops). There are many controversial topics surrounding fuels, from carbon emissions and climate change through the potential for bio-fuel crops to compete with food crops to the whole debate around nuclear power generation. - Description added by: David Lockie

Energy efficiency is widely regarded as the most important first step in making the transition to a low carbon economy. Whilst renewable energy and other measures are also vital components, energy efficiency ensures that valuable energy - whether it be heating, cooling, or electricity - is not wasted. There are numerous energy efficiency technologies, from insulation materials to a plethora of more efficient electrical devices, and more energy efficient vehicles. Explore these pages to find energy efficiency solutions that are right for you. - Description added by: David Lockie