Every type of energy has its own storage issues, but perhaps the hardest challenge is to store electricity. As the proportion of electricity generated from renewable sources increases, the problem of storing it grows too. For example, a solar panel on a roof generates electricity during daylight hours, but we might need that electricity at night (for lights especially). So it is common to use solar panels (or any other intermittent renewable energy device) with batteries that can store a limited amount of electricity for use later on. Unfortunately this tends to work less well for high-demand appliances such as fridges, washing machines and kettles, because the sheer amount of electricity they need would require a really large bank of batteries. New technologies such as fuel cells may create ways to convert this electricity in to hydrogen during times of plenty and then back in to electricity when electricity is needed, but there are efficiency and cost barriers to this that still need to be overcome. - 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

Carbon is such a natural part of so many human activities that many different areas of policy making and decisions are now having to consider it. Planning, energy and economic policies are all being re-examined in many countries to reduce carbon emissions. - Description added by: David Lockie

Renewable and alternative energy sources are set to play an increasingly important role in providing the electricity, heat, cooling and fuels that society needs. There is a wide range of energy sources such as solar (both photovoltaic and solar thermal), wind, bio-fuels and biomass, hydro-electric, geothermal and heat pumps. - Description added by: David Lockie