Hydrogen is the most abundant element in the universe. Hydrogen is an energy carrier - it contains the energy that powers the sun which sustains all life on earth, and hydrogen is found in all living organisms.

Hydrogen is the first element in the periodic table. It is the lightest and simplest element, and each hydrogen atom contains just one proton and one electron. Hydrogen has the highest energy content of any common fuel by weight, but the lowest energy content by volume, and as a result innovative Fuel Storage technologies are required to store pure hydrogen in comparable quantities to fossil fuels. Hydrogen combines readily with other elements and it is not found on earth in its pure form. When combined with oxygen the result is water, and when combined with carbon - hydrocarbon fuels - such as ethanol, gasoline, and coal.

Hydrogen is a fuel which can be used power Hydrogen Internal Combustion Engines and Fuel Cells. When hydrogen is combined with oxygen in a fuel cell, electricity is produced, and the two elements combine to form water in an exothermic reaction (i.e. heat is produced). The water is then usually emitted as a waste product, although in some fuel cell systems the water is recycled or utilised before being emitted.
- Description added by: lowcarbonranger

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

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

Communities consist of homes, businesses and sometimes industrial concerns, with infrastructure like health care, transport, communications, government and utilities. Many decisions about low carbon need to be considered at the community level in order to ensure that ‘joined-up thinking’ is applied to the process. Click the picture to the right to explore our interactive community environment. - Description added by: David Lockie