What Can You Do?
There are currently many options open to home owners regarding the use of renewable energy sources. Various schemes, as detailed below, can be incorporated into most household systems, and can be used in conjunction with traditional heating and electrical systems.
Ground source heat pumps (GSHP) - A GSHP system circulates liquid through specially designed coils or loops of pipe buried in the ground. The liquid absorbs heat from the ground, which at the depth of 1.5 metres is a fairly consistent 11-13ºC throughout the year. A heat pump removes the stored energy and transfers it to a system for heating the building and hot water requirement.
These installations are best coupled to an under floor heating system, but can be linked to other options. Whilst not strictly renewable, every unit of electrical energy required to power the pump produces three to four units of energy extracted from the ground.
The running costs of GSHP systems can be highly competitive against all other fuels and maintenance requirements associated with a conventional boiler are removed. Installation costs depend on the size of building and type of surrounding ground.
Solar Photovoltaics (PV) - This involves generating electricity from the sun's energy. It works best in direct sunlight, but is also effective under cloudy conditions. Panels or PV integrated products are best located within 40° of south at an angle of between 15-60°. PV systems can be retrofitted onto existing buildings or incorporated into current and new buildings. As an example, a 1.8 kWp system of 10 panels costs approximately £10,800 and will produce about 1,600 units of electricity per annum.
Solar Suitability Checker
Cocoon's on-line Solar Suitability Checker can help you explore the potential of solar panels. It can:
- Help you check the size and orientation of your available roof space
- Calculate costs and returns on investment for a suitable solar system
- Show the value of feed in tariffs paid to you over a 25 year period
- Compare price estimates from a number of MCS approved installers
(Cocoon is independent, impartial and operated by United Sustainable Energy Agency, a not for profit organisation, supported by Chiltern District Council.)
Solar water heating (SWH) - SWH takes the radiation from the sun, present in all forms of daylight, to heat a combination of water and anti-freeze that passes through a solar collector mounted on the roof (as for PV). This is then pumped to a conventional hot water tank that has an additional heating coil, from which the heat from the sun is passed to the hot water that comes out of the taps.
Systems can provide a minimum of 60% of annual hot water needs and are always linked to the conventional heating system for back up. There are over 50,000 systems of this type in the UK and they cost from £1,800 installed, depending on size and type of system selected.
Small Scale Wind Turbines - Small wind turbines are sized at a hub height of 25 metres and under. Turbines need to be mounted on a tower of a height that reduces the blocking effect of the buildings, residential properties and trees.
They are noiseless, but a planning application will be required. Wind speeds are the vital factor, with wind speeds of 5m/second and above, at a height of 10m being recommended.
Biomass heating - Woodchips from sustainably managed wood sources are a renewable resource and can be burned in modern, computer controlled boiler plant to provide space and hot water heating in buildings. They work best when there is a consistent heat demand throughout the heating system and a storage area with easy access is required.
Boiler plant costs are higher than for fossil fuels, but woodchips are cheaper than gas, oil and coal.
Reducing our dependence on fossil fuels such as coal, oil and gas for the production of energy is vitally important, in order to reduce the impacts of global warming and climate change. Without doubt, renewable energy technologies will play a key role in achieving this, by providing a clean and sustainable source of energy, whose generation will have no negative effects on the environment.
To see how other individuals and organisations have saved money and made a real, positive impact on the environment please visit the Energy Trust Website where a number of case studies are available to view.
