Renewable Energy

Renewable energy is a term used to describe a variety of energy sources which do not have a finite supply. In contrast, energy sources such as coal, oil and gas are non-renewable forms of energy and will one day run out. In fact supplies of these fossil fuels are already severely depleted and we need to look carefully at other sources of energy with some urgency. Renewable energy sources also have a further advantage over traditional fuels as they do not have the same negative environmental impact caused by CO2 emissions

There are five main types of renewable energy, namely solar power, wind power, hydropower, biomass energy and geothermal power.

Solar power is the name given for using the energy of the sun to provide electricity or to heat water. Both types can be used in both domestic and larger scale environments.

Wind power harnesses the power of the wind to provide electricity.

Hydropower means using the power of water to make electricity or run machinery.

Biomass is a collective term for all animal and plant material. Biomass energy is produced by burning or digesting some forms of these material.

Geothermal power Geothermal energy is the natural heat of the earth which can be used to heat or cool buildings and provide hot water.

Solar Power

The term solar power is used to describe a number of methods of harnessing energy from the sun. As fossil fuel sources deplete and environmental concerns about greenhouse gases increase, renewable energies such as solar power are increasing in popularity across the world including the USA.

There are two types of solar power, solar electric power which use photovoltaic cells to convert solar radiation into electricity, and solar thermal energy where the sun’s energy is used to heat water. Photovoltaic cells consist of one or two layers of a semi conducting material, usually silicon. When light shines on the cell it creates an electric field across the layers, causing electricity to flow. The greater the intensity of the light, the greater the flow of electricity. Solar thermal energy is a relatively simple process where water is pumped into solar panels and, as it passes through them, is heated and then stored in a tank ready for use. The water will stay hot for around 24 hours.

In both cases solar panels are usually fitted to the roof and work during daylight hours, however with a new house being built from the ground-up it may be possible to integrate them more seamlessly into the house. It is a misconception that solar panels only work with direct sunlight and solar power collectors can heat water on a very cloudy day. While solar power will not usually completely support a central heating system or provide enough electricity for all a home’s requirements, a substantial supply of power or domestic hot water can be provided.