At present, the world relies heavily on coal, oil, and natural gas for its energy - fossil fuels which are non-renewable. These fuels draw on the earth’s finite resources that will eventually run out, becoming increasingly expensive and too environmentally damaging to extract as time goes on. Stoves such as those by Stovax which use wood to produce heat can also be classed as non renewable only if the heating is efficient and trees are replanted.

The use of fossil fuels is now accepted worldwide to be contributing to global warming and climate change. Renewable energy - solar, wind, hydro (water), biomass - is constantly replenished and will never run out. Most renewable energy comes either directly or indirectly from the sun.

Solar energy can be used directly for generating electricity, hot water heating and solar cooling, and is suitable for a variety of domestic, commercial and industrial uses.

The heat from the sun creates the winds, and this wind energy is captured by turbines which produce electricity.

Sunlight also causes plants to grow. The organic matter produced by plants is known as biomass. Biomass can be used to produce electricity, heat and transportation fuels such as bio-diesel.

The energy from water flows in streams and rivers comes from the sun - the hydrological cycles are driven by evaporation - and can be tapped to generate power via water turbines, so producing hydro-electricity.

Wave power is generated by winds, which are created by the heat from the sun, whereas tidal power is driven by gravitational energy affected by the sun‘s mass.