Wind energy. Wind Energy, what is it? Network Communities of a sustainable Europe (CoSE)

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1 Wind energy Network Communities of a sustainable Europe (CoSE) International network of RURAL villages and URBAN neighborhoods for bottom-up approach For more information, see: Wind energy Abundant and inexhaustible Large wind turbines in open fields or small rooftop turbines High yields possible Wind Energy, what is it? The energy in wind has been used for ages in sailing and milling. However, since the industrial revolution fossil fuels have gradually replaced wind energy for these, and other, activities. Recently, wind energy has started a revival and currently it is a fast growing sector. Wind energy is generally related to large turbines and wind farms, both on land and in sea. However, wind energy can also be used on a smaller scale. Especially useful in coastal areas Carbon neutral Good social organization required Rooftop wind turbine

2 Technical aspects (preconditions / opportunities) The basics of a wind turbine are its mast, the rotor house containing the generator and the rotor blades. The rotor blades design resembles that of airplane wings. The same principle that gives an airplane vertical lift makes the blades turn in the wind. Bigger surfaced blades have greater lift, but also more drag. Therefore an important calculation in designing a wind turbine is the optimal blade surface. The amount of electricity generated through a wind turbine depends on various conditions. To begin with, there exist various types of wind turbines. Related to the type of wind turbine, are its height and the size of the rotors. Wind turbines have masts ranging from 10 to 135 meters high, with rotor blades diameters ranging from 1 to 120 meters. The larger the blades, the more energy can be produced. In addition to these technical characteristics, contextual factors like for example the wind conditions and the location on which the turbine is constructed, heavily determines its output in terms of generated electricity. Wind speeds of 4 meters per second are enough to power Parts of a wind turbine a wind turbine. However, stronger winds are equivalent to more energy, which makes windy places more suitable for harvesting wind. On the contrary, in rare occasions where wind speeds of over 25 meters per second are reached, wind turbines are stopped to avoid damage. Not only wind speeds but also air density has a profound effect on the amount of electricity generated by a wind turbine. The more dense air becomes, the heavier it is and the more power it applies on the rotor blades. Altitude, temperature and pressure are conditions that regulate the degree of air density. For example, on high altitude air density is lower than on sea level, which makes offshore and seaside locations more suitable for harvesting wind energy. Among smaller wind turbines two classes can be distinguished: the traditional horizontal axis wind turbines and vertical axis wind turbines. Horizontal axis wind turbines Most of these wind turbines have the traditional shape with 2 or 3 blades. More blades are possible and diverse shapes exist, each with their own merits. Horizontal axis wind turbines turn with their blades towards the wind in order to generate most power. This turning however makes them sensitive to turbulence or sudden wind direction changes. They are thus most effective in open areas with stable wind conditions. Vertical axis wind turbines Wind turbines with a vertical axis are especially designed for urban areas. Vertical axis wind turbines do not have to change their orientation to make use of changing winds. Also turbulence has much less effect on their performance. There are many types of vertical axis wind turbines, adapted to many different circumstances. Scale Large wind turbines (80 to 200 meters high) have high yields. However, the investment is also much higher and regulations much stricter. In addition the impact on the landscape is much larger. It is therefore advisable to discuss plans for a large wind turbine with neighbouring communities. To increase the local acceptance it is recommended to let local communities participate in a project and allocate a share of the generated benefits towards the community.

3 Average size onshore wind turbines (2-3 MW) can provide 1,500 households with electricity. On the other hand, offshore wind turbines (6 MW) currently are able to generate enough electricity for 5500 households. Small wind turbines (app. 15 meters high) are available in a large variety of characteristics, each designed for certain conditions. An overview of this variety is given in the table. Type Investment Power [kw] Rotor diameter [m] Annual yield [kwh/yr] Turbine energy use [kwh/yr] Energy Ball 4, Ampair 8, Passaat 9, Skystream 10, Airdolphin 17, Montana 18, Turby 21, WRE , WRE , The above mentioned data are from a test-site in the coastal area of Zeeland, the Netherlands. Local conditions can change yields of the wind turbines and thus their (relative) cost-effectiveness. Benefits for the community Costs Small-scale wind turbines still struggle to become a competitive renewable technology. Average costs for a standalone small wind turbine varies from 2,500 to 6,000 per installed kw. The average costs for small wind turbines that are connected to grid are a bit higher due to additional cost for the required power converter. Therefore their prices range from 2,700 to 8,000 per installed kw. The cost efficiency of middle size wind turbines is comparable to that of photovoltaic solar panels. For investment figures, see the table. Large wind turbines come with large investments, as is rule of thumb 1,400,000 per MegaWatt. Typical large wind turbines have around 3 MW of power. Exact costs depend on the location, scale of the wind project and type of turbine.

4 Revenues Wind is a free, abundant and inexhaustible source of energy. The efficiency of wind turbines depends on the type of turbine, its height, the length of its blades and (local) wind conditions. For Europe wind maps exist which give a general idea of the wind conditions in certain regions. Geography and land use can cause local variance from these large-scale maps. Nevertheless, it can serve as a first indication for the applicability of wind energy in a certain area. A general rule is that higher up the air the wind becomes stronger. Wind turbines therefore have become taller and taller over the years. However, with great length comes great cost. There is always a balance between extra cost for extra height and thus yield. The electricity demand and the wind conditions determine which turbine types are cost-effective under the circumstances. For smaller wind turbines turbulence caused by obstacles such as trees and buildings can reduce the turbine s yield. The effect of obstacles on wind can stretch up to 100 meters. Especially in urban areas this makes it difficult to predict efficiency beforehand. Good research on local wind conditions is therefore advised if you want certainty on the return on investment. Such research can also serve for deciding which turbine type can best be placed, and in what exact location it will be most effective. Social aspects European wide, as well as on the national level, the public opinion towards wind energy is significant and stable. Despite public support on a national level, community acceptance remains a crucial factor for the successful development of wind projects. Wind projects that fail to consider and incorporate local stakes frequently face opposition mainly emphasising aesthetics, that wind turbines are noisy, cause shadow flicker and impact the wildlife. Statistics regarding noise, shadow flicker and environmental impacts: Noise produced by wind turbines is often matched or exceeded by background noises caused by traffic or wind through trees. In absence of these background noises, the noise produced by wind turbines are rarely heard further away than 300 meter. Depending on the position of the sun, residents near a wind turbine might be affected by shadow flicker. The inconvenience and opposition caused by both shadow flicker and noise can be avoided by agreeing to voluntarily suspend the production of a wind turbine under certain conditions. To estimate and ultimately avoid the potential environmental effects of constructing a wind project, it is mandatory to undertake an Environmental Impact Assessment. The annual bird mortality caused by wind turbines is estimated to be very low in relation to for example windows, high-tension lines, cats, vehicles and pesticides. Wind parks can have a negative effect on (small) bird populations on the short term (e.g. during the construction of wind mill parks), but harm can be prevented if the location and timing of construction are thought through. Also, there seems to be little evidence for a negative causal relation on the long term (a decennium). Offshore wind parks can for example have a positive contribution to wildlife: due to the fact that ships cannot come in between wind mills, these areas serve as a breeding room for fish.

5 Opposition towards wind projects can be avoided through incorporating local stakes during the planning and management of the project. In light of this, it is important to understand that local opposition is not merely based on the technology or wind turbines themselves but is often caused by distrust towards developers, authorities and/ or energy corporations and the way they plan and manage wind projects. Furthermore, when local stakeholders have the possibility to own a part of the wind project and thus receive a fair share of the benefits generated by the wind project, is an incentive to participate rather than to resist. Where has it been implemented? Examples CoSE communities Wind energy has not been implemented in any of the CoSE communities. The community of Ommerkanaal, the Netherlands, is faced with a governmental plan for wind turbines in the region. Success and Fail Factors for implementation It is important to take the local wind conditions in to account. Wind speeds and air density affect the efficiency of the wind turbine. The stronger the wind the more electricity is generated. However, wind speeds of at least 4 meters per second are required. In addition, heavier or denser air delivers more power to the blades than lighter or less dense air and hence provides better conditions. The size of the wind turbine in terms of its height and the length of rotor blades, also determine the amount of energy that can be harvested. Higher up wind speeds are stronger than those close to the ground. Furthermore, longer blades catch more wind than shorter blades and therefore generate more electricity. Besides these contextual and technical conditions, the social aspect is at least as import. Whether local stakeholders are incorporated during the process of planning and managing the wind project is crucial for its realisation and ultimately for its success. How to get started? European legislation The European Commission (EC) sets a target of 20 per cent renewables within the EU by Renewables include wind, solar, hydroelectric and tidal power as well as geothermal energy and biomass. Increasing the share of renewables in the EU will contribute in cutting down greenhouse emissions and make it less dependent on imported energy. To reach this ambitious goal the EC has presented the 2009 Renewable Energy Directive. Besides setting a target, the Directive also improves the legal framework for promoting renewable electricity, requires national action plans that establish pathways for the development of renewable energy sources including bioenergy, creates cooperation mechanisms to help achieve the targets cost effectively and establishes the sustainability criteria for biofuels.

6 Each Member State has a national target, which differs between them. Annex I of the 2009 Renewable Energy Directive shows the various national targets. An annual report on the progress of each Member State is presented on the website of the EC. These reports include various aspects such as the current share of renewables, updates on national legislation, all support measures taken, system of guarantees of origin, administrative procedures and many other relevant national measures. Under further reading a link to the national reports can be found. Local knowledge (CoSE partners) No wind energy initiatives have been undertaken so far among the CoSE partner communities. Finding partners Bukkaranyos would like to make wind energy a part of their energy supply. The community is located in an area with a lot of wind and sees wind energy as a good opportunity. Helix Wind Turbine Building a strategy and plan In designing a strategy or plan to realise a wind project, several steps are important to consider. The following steps provide assistance and should by no means be interpreted as fixed. Consulting various stakeholders (locals, municipality, local businesses) Finding and acquiring a suitable location. Several factors might influence the siting: Optimisation of energy production Visual influence including shadow flicker Noise production Distance from possible grid connection Assessing the local wind conditions such as wind speeds and air density Selecting and customising a suitable turbine attuned to the wind conditions Conducting an Environmental Impact Assessment Seeking the required local, regional and/or national permits Demonstrating the economical viability of the wind project Ordering the manufacturer to build the turbine Preparing the construction site The actual construction of the wind turbine Effectively operating and maintaining the wind turbine

7 Further reading The European Wind Energy Association Overview of other European associations (wind is on the bottom) The Europe Renewable Energy Council Wind energy the facts European legislation Homepage: Progress reports: Renewable Energy Directive: uri=oj:l:2009:140:0016:01:en:html Summary of legislations: Articles on the environmental impact of wind turbines:

8 Network Communities of a sustainable Europe (CoSE) International network of RURAL villages and URBAN neighborhoods for bottom-up approach An initiative of the communities of: Ashton Hayes (village in Cheshire-West, United Kingdom) Beckerich (municipality-village in Luxemburg Betlejem (quarter of Reda, near Gdansk, in Poland Bӧcs and Bükkaranyos (municipality-villages in Bükk-Mak-Miskolc-Region, Hungary) De Stoere Houtman (quarter of Arnhem, the Netherlands) Measolle (village in France) Ommerkanaal (village of Overijssel, the Netherlands) Strem (municipality-village in Ӧko-Energie-Bürgerland, Austria) Contact: Jaap Huurman De Stoere Houtman De Houtmanstraat PJ Arnhem Netherlands jaaphuurman@hotmail.com Other communities invited into the network: Blacon (quarter of Chester, United Kingdom Feldheim (invited, village of Treuenbrietzen, Germany) Frankenwald (invited, village near Hof, Germany) Jühnde ( invited, independent village in Germany) Schönau (Schwarzwald, Germany) Vauban (quarter of Freiburg, Germany) For more information, see: Published: March 2013