Types of renewable energy

Wind power
Wind power is probably the most visible and well known form of renewable energy in the UK. People have been harnessing the power of the wind for centuries and today’s wind turbines produce a substantial contribution towards Britain’s energy requirements.

Offshore wind farms promise to deliver huge amounts of energy without objections from local residents and several large scale off shore wind farms are currently under construction.

Solar
Solar power can describe both solar thermal energy (where sunlight is used to heat) and photovoltaic energy (where solar cells convert sunlight directly into electricity). Due to the unpredictable weather in the UK, solar energy has not formed a significant energy source on an industrial basis although solar thermal energy systems can add to domestic energy efficiency.

Hydropower
Hydropower is generated by converting the mechanical energy of water into electricity by passing it though a turbine at high pressure. This is most commonly achieved by harnessing the power of water falling or flowing in fast moving rivers.

Tidal
A form of hydropower that converts energy from the tides into electrical energy. This form of energy generation is still in its infancy but is a promising source for the future. As with wind power, global environmental benefits have to be weighed against localised impact. The most well known tidal project is the controversial Severn Estuary barrier which, if successful, could generate up to 5% of the UK’s total electricity requirements.

Geothermal energy
Geothermal energy involves extracting heat energy from deep within the earth itself. Hot springs have been celebrated since Roman times for their regenerative properties but in the 21st century, the heat trapped under the earth’s surface offers a potentially inexhaustible, reliable and clean source of energy.

Geothermal energy is already common in countries like Iceland where steam produced from hot rocks found close to the surface powers turbines to produce electricity. New technology is enabling geothermal energy to become economical across a much wider area than was possible in the past, adding to its future as a universal energy source. Geothermal energy can also refer to ground source heat pumps which can provide warm water on a small scale to domestic and commercial users.

Biomass
Biomass energy refers to the generation of both gas and electricity from recently dead biological material such as wood, plant matter or even manure. On an industrial scale, biomass can include crops grown specifically for the purpose of burning such as corn, sugarcane and fast growing wood like willow. Despite the fact that these crops produce CO₂ when burned they are classified carbon neutral as the carbon released is recaptured by the growing of new crops.

Biomass energy can also refer to the production of natural gas. Domestic human waste decomposing in landfill sites gives off huge amounts of methane and other gases. This gas can also be captured and converted into electricity or stored for later use.