Buyers Guide Wind Turbines

A buyer’s guide to wind powerTo find out more about installing a domestic small-scale wind turbine call 0800 512 012 or visit energysavingtrust.org.uk • They can be pole mounted or building mounted. making it an ideal candidate for wind energy. Inside the generator the shaft rotates within a magnetic field to create electricity. • • Power generation continues at night and in wintertime. Wind turbines are available in a wide range of sizes. Smaller microturbines (less than 100 watts) are often used to charge 12 volt (V) or 24V batteries for use on off-grid systems. On a smaller scale a domestic small-scale wind turbine can generate power to supply individual buildings with any surplus being exported to the national grid. In larger machines a gearbox is often used to increase the rotational speed.The blades of a wind turbine are connected to a rotating shaft which passes into an electricity generator. your households overall • They can reduceemissions – a major carbon dioxide contributor towards climate change. There are other numerous benefits to wind turbines: The UK has 40% of the European wind resource available. often seen on boats. This guide will focus on systems connected to the electricity grid rather than off-grid battery charging systems. 07 02 A buyer’s guide to wind power . to the local • They can be connected in off-grid systems electricity grid or used with electricity storage such as batteries. In smaller wind turbines the blades are often connected directly to a permanent magnet generator. The technology now generates around 2. Once installed they require minimal maintenance and can be integrated into the electrical distribution system or grid. Domestic turbines generally range from 1 kilowatt (kW) to 6kW. What are the benefits of wind turbines? What is wind energy? The UK benefits from some of the highest average wind speeds in Europe. How do wind turbines work? Wind has been used for centuries as a free source of energy. Today the power of the wind is commonly harnessed by converting the rotation of turbine blades into electricity. Large scale wind farms generate electricity for energy companies much like any other power station.5% of the UK’s electricity and the proportion is increasing rapidly. Between 2007 and 2009 the amount of electricity generated from wind power in the UK increased by over 75%. Windmills utilised this energy to power machinery for physical work like crushing grain or pumping water. a building mounted turbine will not normally generate as much electricity as an equivalent pole or tower mounted machine. This means you avoid the costs of having a free standing tower and foundations. and also the height of the turbine above ground level or on top of your roof. In high winds many turbine heads are designed to turn away from the wind to prevent the turbine being damaged. The Energy Saving Trust recommends that you only consider installing a wind turbine if the annual average wind speed for your site is 5 metres per second (11mph) or more. The turbine head comprising the blades and the generator rotates freely on top of the tower to align itself with the wind. The turbine does not need to point into the wind and so manufacturers’ claim they are more suitable in areas where the wind is turbulent. The windspeed itself is dependent on a number of factors. Designs of these systems vary between manufacturers and include both vertical and horizontal axis machines. However. Vertical turbines have the main rotor shaft running vertically allowing the generator and/ or gearbox to be placed at the bottom near the ground. For domestic machines a securely guyed pole may be more appropriate than a rigid tower. Is a wind turbine suitable for my home? Before you choose to install a wind turbine there are some important things to consider: Local wind speeds – The electricity generated at any one time by a wind turbine is highly dependent on the speed of the wind at the site of the turbine. Horizontal turbines have the main rotor shaft and generator at the top of a tower with the turbine blades automatically pointing into the wind like an aeroplane propeller. You should always seek specialist guidance before installing a building mounted turbine. such as location within the UK. Towers need strong foundations or support to make sure they remain firmly anchored to the ground. Building mounted turbines are a new type of wind turbine designed to be installed directly onto a building. Most turbines for homes have a horizontal axis. . A buyer’s guide to wind power 03 To find out more call free on 0800 512 012.Types of wind turbine systems There are two main designs of wind turbine – those with a horizontal axis and those with a vertical axis. They can be mounted directly on a building but turbines mounted on free-standing towers or poles can be more effective at capturing the winds energy. It may also add stress to your home’s building fabric due to increased weight and vibrations. nearby obstructions such as buildings and trees. Domestic turbines are generally connected into the existing house electricity system via a piece of equipment called an inverter. no matter how it is used (the Generation Tariff). If grid related power cuts are common in your area. The brow of a smooth hill is often the ideal location for a pole mounted turbine. A building mounted turbine in an inland built up area is unlikely to perform well. There should be no significant obstacles such as tall buildings.org. However if possible we recommend you do it for a period of 12 months to get realistic wind speed distribution data as wind speeds vary through the year. This will also reduce the possibility of operating noise causing a nuisance. trees or hedges to maximise the benefit of the wind and reduce wind turbulence. And any electricity you use yourself will save you money on your electricity bill. Ideally wind turbines should be sited as far away as possible from buildings.Connecting to the grid Large wind turbines usually export all the electricity they generate via a direct connection to the grid.org. Any electricity exported will receive a set Export Tariff.grid connected inverters automatically switch off to protect engineers working on the line to repair it. Consult with your installer for further details. When the household is using electricity the turbine’s output is used directly in the house. How much you will receive depends on a number of factors. To be eligible the system and the installer must both be MCS certified. If your home is situated in a sheltered location such as a valley this could diminish a wind turbines performance. for more details on FITs visit energysavingtrust. 07 04 A buyer’s guide to wind power . including wind speed which dictates how much electricity you generate.uk An eligible installation will receive an annual payment for all the electricity generated. we recommend installing an anemometer (wind speed measuring device) to measure the wind speed. If the wind output is greater than household demand the excess is exported to the grid just like a large turbine.for example. However if the grid fails . you might wish to consider some form of back-up storage. trees or hills that are likely to reduce the windspeed or increase turbulence. When the wind speed drops the household takes its power from the grid just like any other house. Make sure that the installer and product are both certified under the Microgeneration Certification Scheme (MCS). You should measure your wind speed for at least three months. You can get an initial indication of likely windspeed using our domestic wind speed prediction tool at energysavingtrust. during a severe storm .uk/ windspeedtool If this indication is promising. Feed-in Tariffs If you install an eligible wind turbine you are entitled to support under the Feed-in Tariffs (FITs). A basic grid-connected wind turbine requires no batteries. export rate of 3p/kWh and electricity price of 12.It is generally better to use as much of the energy generated by your wind turbine as possible.5p/kWh 26.000 including installation.500 to install. A well sited 6kW turbine could earn and save you around £3. an export rate of 3p/kWh and a generation tariff of 26. This avoids the full cost of taking electricity from the local grid and makes maximum use of your own investment in your wind turbine. A typical 1kW building mounted system costs approximately £2. The Feed-in Tariffs are not available in Northern Ireland.5p/kWh. Eligible turbines installed before the end of March 2012 will receive the following tariffs index linked for 20 years: Turbine size <1.670 £220 £310 £3. economies of scale and the cost of the electricity being replaced by using the wind turbine.5 – 15kW Generation Export tariff tariff 34.7p/kWh 3p/kWh 3p/kWh Costs and savings The cost of a professionally installed wind turbine system can vary significantly so it’s important to do as much research as possible. The capital and installation costs for a wind turbine system can be quite high compared with other technologies. export payments and savings on electricity bills. This is based on 75% of generation exported. £ per year Generation Tariff Export Tariff Reduction in current electricity bills Total savings and income generated £2. Rural or coastal dwellings can benefit more easily from wind energy as local wind conditions are often good.200 per year including generation tariff. Make sure you obtain full quotations from manufacturers and installers in order to get the best price. Savings will depend on the turbine type size.5kW turbine costs around £15. Tower and pole mounted turbines will incur significant installation costs but could hold a bigger turbine than if bolting to an existing building and generate more electricity.200 Based on a tariff rate of 26.000 and a 6kW system costs approximately £23. local wind conditions. This should include obtaining at least three quotes from reputable installers. A typical 2.5kW >1.7p/kWh. If you export electricity to the grid you are likely to be paid less than the amount it costs you to buy electricity from your supplier.7p/kWp. Contact the Energy Saving Trust on 0800 512 012 for details of certified products and installers. A buyer’s guide to wind power 05 . Ask at least three installers to specify and cost some potential options for you.org. • Offering you a discount for signing on the day. currently all wind turbines require planning permission. including: Staying in your home for an unreasonably long time. It is also a good idea to consult your neighbours about your plans. Turbine systems generally come with a long warranty period. • Claiming that there is limited availability of a product. So batteries may have to be replaced at some point in the systems life. a typical battery life is around 6 to 10 years depending on the battery type. For battery storage systems. They should supply good quality instructions and operating manuals. Always consult your system supplier for exact maintenance requirements before you commit to installing the turbine.org Check that the installers are members of REAL Assurance Scheme. We recommend you use an installer and product certified under the Microgeneration Certification Scheme. In particular member companies must not use any high-pressure selling techniques. contracts including deposits and payment schedules. For more information about the REAL Assurance Scheme visit realassurance.What to look for in an installer All wind turbine suppliers should be able to provide a detailed breakdown of the specification and costs of their proposed system. completing the order and after-sales activities.uk 07 A buyer’s guide to wind power 06 . Permission Although planning policies are being revised to encourage more people to install renewable energy technologies. Members of this scheme agree to abide by the schemes Consumer Code. A yearly check by a professional installer is recommended. Your installer should provide written details of any maintenance checks you should undertake from time to time to make sure everything is working properly. The code covers issues such as pre-sales activity. • • Offering you a high initial price followed by a discount. as well as provide an estimate of how much electricity will be generated by any proposed installation. you can expect the system to operate for 20 years or more. Maintenance Although wind turbines require regular scheduled maintenance. They should also be able to explain how they have calculated the size of the system to be appropriate for your needs. • Withholding price information from you until the end of the visit. You can find certified installers at microgenerationcertification. Ask: About after-installation services offered. the cheapest may not be the most appropriate. • How long have they been in business? will project manage the they the estimate of • How muchhave calculatedbe generated and • If the companycoordinate the erection of whole job and how electricity will the assumptions they have used in that calculation.all installers shouldon provide a minimum one year warranty the installation. Pick a supplier with experience. Ask for a list of references and local installations and check them out. Get lots of information on system options and potential problems so you talk confidently to installers. the turbine. performance of the systems • • About relativeyou are comparing data – make sure measured under the same test conditions. is – Is the • About whattheincludedincluded?price of erecting turbine • • For any background information and test data. Check any professional credentials being quoted. Ask: A buyer’s guide to wind power 07 . including health and safety guidelines and how the installer will address them. • About payment options. Ask: How many years they have been installing systems? options. Check the time limits of any guarantees and warranties and find out what they cover.Use the checklist below to help you select the right installer for your needs. • • About warranties . • For details on availableof powerfor example size. Ask: About government incentives – your installer will have to ensure that the system is eligible for FITs payments. of • For detailstimewhat the warranty covers and over what period. Ask: For recent manuals and brochures. • Check quotations for detail. Ask if they are a member of an appropriate trade organisation and check that they are suitably certified. Choose local where possible. • For information on regulations that apply. Many competent and experienced installers may not have any relevant professional qualifications. likely generation and maintenance cycles. Do not compare installers on cost alone. This is very important as it will make the process much easier for you. make sure you discuss the limitations of that database and check the results against the Energy Saving Trust domestic wind speed prediction tool. If they have used a wind speed database only. Our advisors will: Give you personalised advice on what’s practical for your home.org.org.uk or call us free on 0800 512 012.org.uk EC324 © Energy Saving Trust January 2011. Printed on Revive Silk which contains 75% de-inked post-consumer waste and a maximum of 25% mill broke. To start generating your own energy visit Energy Saving Trust energysavingtrust. • Tell you about grants and offers available. Please refer to our website for the most recent measure costs and savings. London SW1H 9BP Tel. .org REAL Assurance Scheme realassurance. E&OE. However financial savings will change as energy prices rise or fall. To find out what you can do to generate your own energy visit energysavingtrust. RenewableUK renewable-uk.org.uk (trade association of the UK wind energy industry) • • Put you in touch with local certified installers. Energy Saving Trust 21 Dartmouth Street.How the Energy Saving Trust can help The Energy Saving Trust is a non-profit organisation providing free.org. impartial advice to help you stop wasting energy and money and help fight climate change.com Energy Saving Trust domestic wind speed prediction tool energysavingtrust.uk/windspeedtool All measure costs and savings are correct at time of printing. 0800 512 012 energysavingtrust.uk Microgeneration Certification Scheme microgenerationcertification.