In recent years, renewable technologies have become a more realistic prospect for home owners. In addition, a range of grants are available to support the initial costs of installation. In addition, several options now have pay back periods of just a few years. For further information on any of the technologies visit www.cheshirerenewables.org.uk or call the Energy Efficiency Advice Centre free on 0800 512012.
Passive Solar Design
The simplest way of harnessing the sun’s energy is converting light into heat through careful building design and planning. Few houses are currently planned in this country to maximise heat available from the passing sun. It involves having large south facing and small north facing windows to maximise solar gain. This is best done in new build projects, or as part of a major refurbishment. Existing buildings can benefit from a similar effect from the addition of a south facing conservatory. Ground Source Heat Pumps operate on a similar principle, using passive solar energy stored in the ground. But they are best installed in new build as they require the installation of a long loop in the ground underneath the building.
Solar Water Heating
SWH uses the energy of the sun to heat water passed through narrow pipes in a panel on a (ideally) south-facing roof. The panels are connected to a hot water cylinder to store the heated water. In the UK a solar hot water panel can provide 100% of hot water needs in summer and 10 -50% in winter. Therefore it does need to be supplemented with another source of hot water heating. There are two types of system, flat plate and evacuated tube. They are similar in principle but the evacuated tube is slightly more efficient as the pipes are situated in a vacuum. The evacuated tube system is also more expensive. A typical SWH system can save 9 tonnes of CO2 in its lifetime and save £60 -70 a year on heating bills. Planning permission is not normally required, but check with your District Council first. Costs vary according to size, type of roof and location, but are between £2,500 – £4,000. Payback is between 15-20 years. Grants are available from government and some District Councils. For more information visit www.solartradeassociation.org.uk
Solar Photovoltaic (PV) Panels
PV panels convert sunlight into electricity. The panels are made up of several cells to give the desired electrical output. They can supply up to 50% of a homes needs. There are 3 types of panel, monocrystalline, polycrystalline and amorphous silicon. The 3 types have decreasing efficiency and therefore cost. Currently, PV panels are relatively expensive, between £8000, £18,000; although grants of up to 50% toward the cost are available from government. Over its lifetime a system could save 16 tonnes of CO2 and £75 – £125 a year on bills. Visit www.pv-uk.org.uk for more information
The UK has the greatest potential wind energy resource in Europe but currently only 1% of our power comes from the wind. It is also one of the most developed and cost effective technology. Small scale wind turbines on a roof top generate around 1kW. At a cost of £1500, they have a payback of 5-7 years. They will save one third of your electricity bills and save 32 tonnes of CO2 over their lifetime. They are subject to planning permission, although the planning laws are due to be relaxed to enable greater take up of roof mounted turbines. Speak to your local District Council to discuss. For more information visit www.bwea.com
Biomass is the term for organic matter such as wood, wood chip, wood pellet, or fuel crops (such as willow, hazel or miscanthus). It is carbon neutral in that the carbon emitted when it is burnt is equal to the amount absorbed during growth. Biomass is suitable for home use as either a stand alone fire or as system linked to space and water heating. Both can be fed biomass as wood pellets or logs. A biomass boiler system can save 100 tonnes of CO2 in its lifetime and around £5000 depending on the system. For more information visit www.r-p-a.org.uk or www.logpile.co.uk
The power of water has been harnessed to generate energy for many centuries. Hydro-electric power uses the force of moving water to generate electricity via a turbine connected to an electricity generator. These can be connected to the electricity grid (where excess can be sold back) or be part of a stand-alone system (where excess can be stored in a battery). A home with access to even a small, yet steady, flow of water could generate electricity at a lower cost than other renewable technologies. Central government grants can assist with the cost of building a system. For more information visit www.british-hydro.org or www.hydropower.org
Combined Heat and Power
Combined Heat and Power (CHP) is a fuel-efficient energy process in which both heat and electricity are produced simultaneously. The heat generated when fuel is burnt to produce electricity is captured and put to use, in conventional energy systems this is normally wasted Typically this achieves a 35% reduction in energy use as well as ensuring a secure supply from having an independent source of power. Furthermore, because it often supplies electricity locally, CHP can also avoid transmission and distribution losses. For more information visit www.chpa.co.uk