How To Understand The Environmental Consequences Of Wind Power

Transcription

1 THE ENVIRONMENTAL IMPACT OF WIND POWER Results from within the Vindval research programme

2 Orders PHONE: +46 (0) FAX: (0) ADDRESS: CM-Gruppen, Box , SE Bromma, Sweden INTERNET: The Swedish Environmental Protection Agency PHONE: + 46 (0) , Fax: + 46 (0) nature@naturvardsverket.se ADDRESS: Naturvårdsverket, SE Stockholm, Sweden INTERNET: ISBN: Naturvårdsverket 2008 Production TEXT: Anna Norlin DESIGN: IdéoLuck AB PRINT: CM Gruppen AB PHOTO: Hans Blomberg, cover photo, 21. Ulf Huett Nilsson/Johner, 4. Thord Norman, 6, 16. Matton, 10. Ljudmiljögruppen, University of Gothenburg, 13. Björn Fagerholm, 18. Ulla Falkdalen, 22. Anders Tukler, 30. Matton, 34.

3 THE ENVIRONMENTAL IMPACT OF WIND POWER Results from within the Vindval research programme SWEDISH ENVIRONMENTAL PROTECTION AGENCY

4 Preface Our future energy supply faces multiple challenges. Electricity production is one of the leading causes of the world s climate and environmental problems. If carbon dioxide emissions from the energy sector are to be reduced, investment in alternative energy sources is a necessity, and wind power has an important role to play. The EU has set a goal for its member states to generate 20 percent of their energy needs from renewable sources by To achieve this goal, Sweden plans to expand wind power as an energy source. Sweden s current long-term goal is to reach a wind power capacity of 10TWh a year by At the end of 2007, at the request of the Swedish Government, the Swedish Energy Agency proposed a new goal for the expansion of wind power up to The proposal would mean a significant increase in wind power production, from 10TWh in 2015 to 30TWh in The proposed new goal for wind power construction has not yet been adopted by the Riksdag. At the end of 2007, based on numbers of green certificates issued, Sweden had 860 wind turbines which generated a total of 1.4TWh of electricity. To achieve an annual production of 30TWh the number of wind turbines would need to increase to between 3000 and 6000, depending on capacity. Hence we may expect a rapid expansion of wind power in Sweden in coming years if the planning goal is adopted. In the course of the planning process ahead of a decision to build a wind farm, the operator must investigate its impact on the environment. Vindval s task is to facilitate the growth of wind power by compiling background data for environmental impact statements and permit application processes, based on the results of scientific studies. The present booklet presents results and ongoing research in the Vindval programme. It opens with a summary of the relevant fields of research, which are then described in greater detail. If you would like to know more about the project areas we recommend that you consult the reports (see Literature and References). We hope you find The Environmental Impact of Wind Power rewarding reading. Vindval i februari 2008 Kjell Grip Chair, Vindval Programme Committee Kerstin Jansbo Programme Manager, Vindval 2

5 Contents Preface 2 The Vindval research programme 5 Research within Vindval provides knowledge about the environmental consequences of wind power 7 Vindval facilitates the planning processes 9 interview with Alexandra Norén, The Swedish Environmental Protection Agency and Programme Committee for Vindval How wind power affects humans 11 The sound created by wind turbines differs in sparsely populated and densely populated areas 12 interview with Eja Pedersen, researcher Collaborations in Wind Power Projects 14 Vindval s work is important for the establishment of future wind turbines 15 interview with Robert Johannesson, The National Board of Housing, Building and Planning and Programme Committee for Vindval How wind power affects life in the sea 17 How does offshore wind power affect fish and fishing? 19 interview with Lena Bergström, researcher and Håkan Westerberg, The Swedish Board of Fisheries and Programme Committee for Vindval How wind power affects birds and bats 23 We now know more about how birds see wind turbines 25 interview with Jan Pettersson, researcher Birds in mountain areas 26 As interest in wind power increases, more knowledge is required 28 interview with Ingegärd Widerström, County Administrative Board for Kalmar County and Programme Committee for Vindval Planned wind farms 29 Wind power in Sweden 31 The research provides invaluable knowledge about the environmental consequences of wind power 33 interview with Lars Andersson, coordinator of issues relating to wind power at the Ministry of Enterprise, Energy and Communications and Expert Panel for Vindval International outlook 35 More knowledge is still needed 38 Literature and References 39 3

6 4

7 The Vindval research programme Wind power is a renewable energy source that has huge, global environmental benefits. It does not cause environmentally hazardous emissions and it uses a resource that is infinite and free. All that we currently know about wind power shows that it has a low, local impact on the environment. At the same time, it is important from an environmental point of view for wind farms to be positioned in optimal locations and for people living nearby to feel part of the process to establish the farms. Therefore, it is necessary to have reliable and scientific data. Compiling this basic data is one of the Vindval research programme s tasks. Facilitate the expansion of wind power Vindval s objective is to facilitate an increase in the expansion of wind power by compiling basic data for environmental impact assessments (EIA) and permit application processes. Research within Vindval helps compile knowledge about how wind power affects plants and animals in the marine environment, how the landscape is affected and what effect it has on people. Vindval will also contribute to the increase of competence in and knowledge about the environmental effects of wind power at Swedish universities, colleges, institutes and companies. A collective national awareness is important in order to urge on the general development of offshore wind power in Sweden. This is currently the starting point for Vindval s work. Focus so far on offshore wind power Vindval started in 2005 and will continue until Today, 18 projects within the programme have been granted funds. Vindval will possibly be extended and, if it does continue, new projects will start up in The Swedish Energy Agency finances Vindval and has commissioned the Swedish Environmental Protection Agency to run the programme. Vindval s work is being conducted at planned and launched wind farms, so-called pilot farms, supported by the Swedish Energy Agency. If Vindval 5

8 is extended, the research and development projects within Vindval will be conducted in parallel with the farms established during the continuation of the pilot project between 2008 and Studies of the environmental effects of offshore wind power will, henceforth, be up-to-date. If Vindval continues after 2009, the focus will also be on the studies of the effects of land-based wind power. There is also a requirement to carry out wind-related studies that are disconnected from the pilot farms, such as multi-disciplinary studies within behavioural sciences and social research. Vindval a model for continued research In the government bill on wind power Miljövänlig el med vindkraft åtgärder för ett livskraftigt vindbruk (Environmental-friendly electricity with wind power measures for the viable use of wind), Vindval is described as a model for the continued research on the environmental effects of wind power by the Swedish Energy Agency as well as the Swedish Environmental Protection Agency. The government also stresses the importance of municipalities, county administrative boards and other authorities actively contributing to improved conditions for the planning of locally rooted, renewable and long lasting electricity production from wind. Included in Vindval s task is the distribution of information. The aim of this report is to explain what Vindval stands for, what results have emerged and to describe the research that is being conducted. Our hope is that the information will be of help to politicians and decision-makers, to administrators and investigators within municipalities and on county administrative boards and for various job types within the wind power industry. 6

9 Research within Vindval provides knowledge about the environmental consequences of wind power Vindval helps compile more knowledge about how wind power affects plants and animals in the marine environment, how the landscape is affected and what effect it has on people. Why do researchers within Vindval study how some species and not others are affected by wind power? There are several reasons, economical and ecological. For example, the species that are studied can be commercially important. Any environmental changes can be hugely significant economically for these species from a broad social perspective or for a certain job type. Some species are so-called key species in the food chains. This means that any type of impact that causes these species to change in any way will also affect other species in the food chains. Again, other species can possess such qualities that are particularly interesting to study. For example, they can be benthic fish, fish particularly sensitive to sound, habitat-forming algae and important food organisms. For example, more people living in the countryside experience disturbance than those that live in residential or densely populated areas. How are people affected? Environmental medicine research within Vindval shows that few people are disturbed by the sound coming from wind turbines. However, a person s living environment is one of the factors that influence the extent of the disturbance. For example, more people living in the countryside experience disturbance than those that live in residential or densely populated areas. A likely explanation for this is that the environment in densely populated areas is more disorganised, both visually and in terms of noise, than in the countryside where the sound coming from wind turbines can be made out much clearer. Two different research projects relating to people s attitudes and acceptance of wind turbines being established are currently being conducted within Vindval. In one of the projects, it is being studied how the various methods and strategies for planning and communication relating to the establishment of wind turbines influence the local population s attitude towards wind power. The other project identifies the different actors strategies in order to overcome opposition and gain more support from the local population. 7

10 Studies show that the risk of small migratory birds and seabirds colliding with offshore wind turbines is very low. How is life in the sea affected? Knowledge about life in the sea and the environment that exists under the surface of the water is still lacking in relation to other environments. Yet, we know that the marine ecosystems have a rich diversity of species and genetic variation. The marine ecosystems are affected by both a natural course of events and human activities. All forms of human activity have an impact on the environment. Wind power is a relatively new activity, whose impact on the environment has not long been scientifically studied. Maintaining the ecosystems natural structure, function and productivity is fundamental in marine administration. An understanding of the factors that trigger changes in the ecosystems is required for this work. Even if research until now has shown that the impact of wind power on life in the sea appears to be minor, the effects of a wind farm must be placed in relation to another form of impact that already exists so that the effects can be assessed in comparison to each other. This is why environmental testing is necessary. According to a research project within Vindval, which studies how sound affects the marine environment, predatory fish, such as perch, trout and roach, are not particularly sensitive to sound and are thought not to be disturbed by sound coming from wind turbines. Some benthic organisms, such as the Limfjord oyster, are also thought not to be affected by the sound of wind power either. A larger research project is currently being conducted within Vindval about the effects of offshore wind power on fish and fishing. One of the questions at issue is to study whether the foundations of the wind turbines act as an artificial reef that attracts fish to it or whether the fish avoid the area surrounding the wind turbines due to the fact that they are disturbed by the sound coming from the farms. How are birds and bats affected? Studies show that the risk of small migratory birds and seabirds colliding with offshore wind turbines is very low. As a rule, seabird flocks tend to keep their distance from wind turbines at an average distance of 1.4 kilometres in good daytime visibility. However, there is some risk of bats colliding with the rotor blades, but this can be redressed by positioning the turbines correctly and possibly stopping the turbines when the wind blows at less than 4 metres per second. A study within Vindval shows that birds can clearly see wind turbines, better than people, especially at short distances. Research about the effect of wind power on birds in a mountain environment is another project currently in progress. Detailed territory mapping and direct observations have been carried out that will constitute comparative material for continued studies once wind parks have been erected. 8

11 Interview with Alexandra Norén: Vindval facilitates the planning processes Alexandra Norén, handles issues relating to wind power at the Swedish Environmental Protection Agency and is a member of Vindval s Programme Committee What are your expectations of Vindval and the research being pursued within the programme? The objective is to compile scientific facts about the environmental effects of wind power and to facilitate the work with environmental consequence descriptions making permit application processes quicker and more reliable. Vindval will also be a meeting place and a forum for researchers where new research can be initiated this is also important. We will gain an increased understanding about attitudes towards wind power and we will be able to draw conclusions about how establishing wind turbines can be handled better and facilitated. It is my expectation that these three objectives will be fulfilled. How do you think you have succeeded so far in fulfilling these objectives? I think that Vindval has come a long way if you look at the studies that have been reported. It is already clear that Vindval plays an important role in the planning process. For example, the Swedish Environmental Protection Agency refers to Vindval when we comment on matters concerning the establishment of wind turbines. Can Vindval contribute to a more comprehensive shared view amongst authorities when it comes to the environmental effects of wind power? Yes, I really hope so. We must take our task seriously and use the results that emerge as a starting point. Research thus far has shown that wind power generally has a very limited local impact on the environment, which can be very positive. For example, the foundations of offshore turbines can act as artificial reefs. What are your visions for Vindval? We need to distribute the results from Vindval to an even greater extent to county administrative boards, municipalities and the wind power industry. Facts must be conveyed in an educational and easy-to-understand manner. Those who deal with planning, permit applications and expansion must have access to concrete results that facilitate the assessment of correct positioning for wind turbines. It is also interesting to know how any negative environmental consequences can be avoided or reduced. How do you see the future development of Vindval? I believe it is time to focus more on the research of wind parks on land, not least in the mountains where the wind can blow as much as at sea. We should be able to evaluate where wind power can be coordinated with others interests such as housing, culture, environmental protection, outdoor life, tourism and reindeer farming. I would also like to see more research concerning people s attitudes. People s participation in the decision making process and good support for the establishment of wind turbines amongst the local population is a central issue and we must think long-term. Establishing turbines in the wrong place can change people s attitude and in time have an effect on the expansion of wind power people s confidence is easily damaged and takes a long time to rebuild. 9

12 10

13 How wind power affects humans How do different methods of working influence the general public s attitudes to wind power projects in the sea? Researchers ask themselves this general question in one of Vindval s projects. Which methods and strategies for planning and communication that wind power developers, politicians and civil servants, on a local and regional level, adhere to has been studied within the project. How local and regional media report about the plans and development concerning the wind parks being studied is also analysed within the project. 1 Comparison of acceptance The researchers make comparisons between various places where the general public has shown different levels of acceptance in relation to offshore wind power. The municipalities of Torsås, Mörbylånga in Kalmar County and Skurup in Skåne County are included in the study. The wind power projects included are Utgrunden I, Utgrunden II, Yttre Stengrund and Trolleboda in southern Kalmarsund. The Abbekås project is being studied in Skurup municipality (the project was put on ice in 2002). Lillgrund in Malmö municipality is also included as an object of comparison. How the different actors work, in relation to the general public and industry and trade, continues in the places where wind turbines are being established will be followed up within the research project. In this way, the study highlights both the time before and after the establishment of offshore wind turbines. 2 Results from the study are expected in The research project is entitled Lokala förankringsprocesser vid vindkraftsetablering (Local support processes when establishing wind turbines). The researchers are Lars Aronsson and Sanna Mels at the University of Kalmar. 2 Since Utgrunden II in Kalmarsund has been postponed, it is only included in the preliminary study. 3 The project is being managed in close cooperation with Mikael Klintman and Åsa Waldo at Lund University and their project entitled Collaborations in Wind Power Projects. The cooperation will also end in a joint synthesis report. 11

14 Interview with Eja Pedersen: The sound created by wind turbines differs in sparsely populated and densely populated areas Eja Pedersen, researcher within Environmental Medicine who, within Vindval, has studied how sound coming from wind turbines affects people Few people are disturbed by the sound coming from wind turbines. This is Eja Pedersen s observation, researcher within Vindval, who has studied how people react to sound coming from wind turbines and presented the results in a doctoral thesis within Environmental Medicine in There is a fear amongst the general public that the sound coming from wind turbines is disturbing. Therefore, an aim of Eja Pedersen s study was to find out how common it is for people living in the vicinity of wind farms to be disturbed by them. The study is the first of its type and fills a knowledge gap since, previously, the studies focused mostly on people s attitudes towards wind power. I realised that data about how people are affected by the sound was missing and this is data that is required for environmental consequence descriptions, for example. An objective and systematic foundation was missing, explains Eja Pedersen. Relatively low sound level Eja Pedersen s research describes what proportion of the residents in the vicinity of wind turbines are disturbed by various sound levels, which factors influence the disturbance and whether the sound affects people s health. The study is based on two questionnaire investigations and in-depth interviews with 15 people. Several areas in southern Sweden have been included in the study: Laholm, Tjörn, Öckerö, Lysekil, Varberg, Landskrona and Simrishamn among others. Different types of landscape, from flat agricultural landscape to more hilly and complex terrain as well as housing in rural areas, suburbs and residential areas have been studied. In Sweden, wind turbines must be positioned so that the sound that reaches the local residents does not exceed 40 decibels. 5 This is a low sound level when compared to other sources of noise such as cars, aeroplanes and trains. Most of the local residents in the study did not consider the sound coming from wind turbines as being disturbing. However, it was shown that people s living environment influences the disturbance experienced. When asked, about five per cent of those living in a varied landscape and in residential areas said that they felt disturbed by a sound level of just under 40 decibels, while a good ten per cent of those living in a flat landscape in the countryside felt disturbed by the same sound level. In densely populated areas, those asked experienced, in principle, no disturbance at all from the sound of wind power. The explanation can be that this environment is disorganised, both visually and in terms of noise. In the countryside, there is open landscape and straight lines with the sound of nature in the background, explains Eja Pedersen. 4 Eja Pedersen (2007) Human response to wind turbine noise. Perception, annoyance and moderating factors, University of Gothenburg. 5 The guidelines apply at 8 metres per second at a height of 10 metres with a tailwind. 12

15 Eja Pedersen has studied the impact of noise on people in the city and the country. A caravan with a sound level meter attached. Greater sound disturbance if the turbine can be seen The irregular sound of the rotor blades that continually increases and decreases in strength is a particular character of the sound of wind power that is perceived especially well by the ear and can therefore be considered disturbing. This sound is not as easily concealed in the countryside where the background noise level is low. People s expectations of the living environment can also play a part. Many people have settled in the countryside for the peace and quiet and therefore experience the sound as being more disturbing. The visual impression of wind turbines is also significant. The risk of disturbance increases if the wind turbine can be seen from where you live. The eye is naturally drawn towards movement, which can mean that the sound becomes much easier to notice. It can also be that if the wind turbine cannot be seen, there may be a building in between, which in itself dampens the sound, says Eja Pedersen. One of the questions that the research sought an answer to was if there were any health risks linked to the sound coming from wind turbines. Any such direct link could not be found. However, some of the people who felt disturbed by wind turbines could experience reduced well-being, says Eja Pedersen. Eja Pedersen s research shows that there are places that are less sensitive to disturbance than what we had previously thought, such as more urban environments. Today, wind turbines are most often positioned in areas as isolated as possible, but the study shows that it is the residents in these environments that risk becoming disturbed the most. Eja Pedersen is now continuing to conduct similar studies in The Netherlands, which will provide some interesting comparative material. 13

16 Collaborations in Wind Power Projects The planning and establishing process of wind turbines often involves huge challenges when it comes to the coordination between the population, Decision-makers and contractors. One of the challenges is finding the right location from a technical, ecological and human perspective. This applies not least to the offshore and inshore wind turbines. Research is currently being conducted within Vindval to identify strategies in order to overcome any opposition that may arise during the construction of wind turbines. Knowledge about the obstacles that arise from the various actors attitudes to the establishment of wind turbines will be used to develop strategies in order to support the establishment of wind turbines better and to facilitate the process of finding suitable locations for wind parks. 6 Coordination between actors The project follows the establishment of Lillgrund in Öresund and Utgrunden II in Kalmarsund where the coordination between various actors is being studied. Local politicians, civil servants, representatives for wind power companies, special interest organisations and the local population in the areas concerned are interviewed. The establishment of wind turbines is followed over time in order to study which conceptions the various actors have before, during and immediately after the establishment of the turbine. 7 National and international research is compared Within the project, an international outlook is also conducted where local experiences from the establishment of wind turbines in various places in Europe are gathered together to form a joint analysis. Previous research projects concerning the establishment of wind turbines have often been initiated locally. There lacks comparative international overviews of the local establishment of wind turbines, especially when it comes to offshore wind turbines. The knowledge inventory will provide an overview relating to which conclusions have been drawn in Swedish and international social and behavioural scientific research with regards to people s conceptions of wind turbines on land and at sea. Results are expected at the end of The research project is entitled Collaborations in Wind Power Projects. The project leaders are Mikael Klintman and Åsa Waldo, Lund University. 7 Utgrunden II is only included in the preliminary study. 14

17 Interview with Robert Johannesson: Vindval s work is important for the establishment of future wind turbines Robert Johannesson, investigator for the National Board of Housing, Building and Planning, member of Vindval s Programme Committee Even if it can be said that wind power generally does not have a particularly large impact on the environment, it does not make sense to turn a blind eye towards the difficulties that can exist. It is better to learn about objective knowledge. Robert Johannesson believes that Vindval has already created such knowledge. What realistic opportunities have Vindval for contributing to a better foundation for planning work relating to wind power? The results that have already come from Vindval will be hugely important when it comes to assessing wind power projects in the future. For example, I think about the study relating to birds in Kalmarsund and the research concerning bats. Both projects provide important knowledge, making it possible to say that, thus far, wind power has not had any fundamental impact on seabirds as concerns population level and that we must take bats into special consideration during the localisation and construction of the farms. How do you think Vindval has succeeded so far in fulfilling its objectives? I am positively surprised and hope that Vindval provides more results along the same lines. Unambiguous and clear results are good as a basis for decisions. Increased knowledge provides the opportunities for positioning the wind turbines correctly. What do you think about the generalisability of Vindval s results? I am amazed at how Vindval s research is as close to the field of application as it is. However, generalisability can be a little difficult to assess. Some results are generalisable to a large extent, such as those relating to seabirds, whilst others are probably more local. For example, research concerning people s attitudes can be difficult to generalise since attitudes can change and are dependent on time and place. In other words, there is a wide span of results including everything from results that are largely generalisable across the world to results that are of more local or regional interest. Even if some results cannot be directly applied in other places, the research can still provide a vital hint as to whether a certain aspect is important enough to take a closer look at. For example, this is the case concerning bats or the question about how people perceive a new wind farm. Which areas should Vindval focus on in the event of a continuation of the programme in the future? It is interesting to look more at how the establishment of wind turbines affects the environment in forest landscapes in South Sweden and in northern mountain areas, but not the mountaintops themselves. Even if the establishment of offshore wind turbines is expected to take time, it is still important to continue studies explaining the conditions there. Long time series are often required in order for the results to be truly reliable. Just because the establishment of offshore wind turbines takes time, the prerequisites for accomplishing this now exist. 15

18 16

19 How wind power affects life in the sea Do perch, trout and roach react to sound coming from wind turbines? Within Vindval, research is being conducted about how wind power affects life in the sea in a variety of different areas one of them being how sound affects the marine environment. It deals with how sound from wind turbines affects everything from predatory fish to smaller animals and organisms as well as sea plants. Previous studies show that organisms in the sea rapidly become accustomed to the sound and vibrations that wind turbines emit under the surface of the water. However, there are still a few questions to answer, such as those relating to the potential effects of stress and escape behaviour. Certain species of fish are studied Perch, trout and roach do not appear to be particularly sensitive to the sound that is produced by wind turbines. This is highlighted by a study within Vindval that has been carried out in a laboratory. The aim was to study whether there is any sort of change in behaviour, such as stress and escape response, when they are subjected to sound corresponding to that produced by wind turbines. 8 The experiment demonstrated that none of the species showed any response to the sound. Perch and trout were mostly passive, both in the control environment and in the environment that was subjected to sound. The roach were more active and swam for most of the time, but their behaviour was the same in the control environment as it was in the environment subjected to sound. 9 Frequencies between 6 and 180 hertz were used during the experiments, corresponding to the lowest peaks in the sound that has been documented 8 The project is entitled Ljudeffekter av vindkraft på rovfisk (Effects of the sound of wind power on predatory fish). The project leader is Ulf Båmstedt at Umeå University. 9 Similar tests are currently being conducted in order to study whether sound from wind turbines affects the level of stress and food intake of perch and trout. The results will probably be released in May

20 from the wind turbine at Utgrunden I. 10 Combined troughs of 1 cubic metre each were used where the fish could change trough by swimming through a tube. There was artificial vegetation in the troughs where the fish could seek cover. A similar trough set-up was used without sound for the control. Studies of the Limfjord oyster Neither was the Limfjord oyster considered to be affected by the sound coming from wind turbines. Preliminary results show that there are not any clear signs that the sound coming from wind turbines affects the speed with which an oyster buries or its activity when it comes to searching for nutriment. 11 The Limfjord oyster is common in marine soft-bottoms and is an important source of food for many species of fish, especially flatfish. The Limfjord oyster naturally lives buried in the seabed where it feeds on bacteria and microscopic animals. In the event of danger, the Limfjord oyster buries down into the sediment in order to seek cover. The studies of the Limfjord oyster are included in a project where the behavioural changes and activity patterns of marine benthos are studied in a laboratory. The aim is to study how sound from wind turbines affects different benthic organisms. Underwater sound is recreated in the laboratory by relocating a mechanical sound wave in the water. The acoustic pressure roughly corresponds to the maximum sound experienced at a distance of metres from a wind farm the size of Utgrunden I in Kalmarsund. Are fish attracted to wind turbine foundations as artificial reefs, or does the noise drive them away? These are some of the questions that researchers at Vindval hope to answer 10 Ingemansson The project is entitled Vindkraftens effekter av ljud- och ljus på mjukbottenfaunan (The effects of sound and light from wind power on the benthos). The project leader is Åke Granmo. 18

21 Interview with Lena Bergström and Håkan Westerberg How does offshore wind power affect fish and fishing? Within Vindval, Lena Bergström and Håkan Westerberg conduct research on the effects of offshore wind power on fish when it comes to sound sensitivity and migration behaviour. A couple of general questions within the project s four study sections are: What are the effects of offshore wind power on fish and fishing? How is the migration behaviour of fish affected by the establishment of wind turbines? Researchers look at the effects wind power has on fish that live in the open sea and on fish that live near the seabed by the coast (pelagic and bottomdwelling fish). How the migration behaviour of eels is affected by the establishment of wind turbines is also studied. In addition, mapping of important living environments for fish and of how fish distribute themselves around offshore banks is carried out. This mapping is carried out with the help of GIS modelling. 12 How are fish affected by the foundations of wind turbines? Two key questions at issue provide us with our starting point in our research relating to how fish are affected by wind power; is there a reef effect, where the foundations of the wind turbines attract fish to them, or is it rather that the fish avoid the area surrounding the wind turbines due to the sound coming from the farms, explains Lena Bergström, who is a project leader. Herring is the most common species when it comes to fish that live in the open sea. The studies are carried out in the vicinity of Utgrunden I in Kalmarsund and in two comparative areas. The method used is echo sounding. There are still no results available. The analysis is in progress and a final report is expected to be ready in After that, another project section will be addressed, which deals with the distribution of fish in the immediate vicinity of the wind turbines. The effect of sound on fish During 2008, another study section will commence relating to bottom-dwelling fish, where cod and flatfish are the most common species. This study will be carried out at Lillgrund in Öresund. The reef effect contra the sound sensitivity of the fish will also be studied here. The effect of the sound of the wind turbines on the fish represents a significant knowledge gap for the research within Vindval to fill in. Does the sound from wind turbines that is emitted in the water have a negative impact on the behaviour of the fish? Today, we have too little knowledge about how fish behave towards sound and if underwater noise can affect their spawning behaviour and consequently reproduction, believes Lena Bergström. Fish population is mapped Another study section within Vindval s research relating to fish is the mapping of the population of fish in the Kattegat with the help of GIS modelling. The objective is to develop analytical methods in 12 A Geographic Information System (GIS) is a computer-based system for gathering, storing, analysing and presenting information linked to a location. 19

22 order to map nature types that are important for fish, which provide new opportunities and contribute to a better foundation for the planning and permit application processes concerning offshore wind power. GIS modelling is a relatively new technique that is being requested more and more. Provisional maps of certain areas in the Kattegat are being developed within the project. The method provides us with knowledge about the areas in which there is likely to be most fish and how the environment looks in these areas. This is then checked through test fishing with fish traps or nets, informs Lena Bergström. The impact of electrical cable Another knowledge gap for Vindval to fill is how the migration behaviour of fish is affected by wind turbines and the electricity transmission cables that are connected to the turbines. A special study has been carried out here on the migration behaviour of eels in relation to AC (Alternative Current) cables and the potential effects of electromagnetic fields. Previous studies concerning DC (Direct Current) cables have shown that the inbuilt compass of the fish experiences interference due to the electromagnetic fields that surround the cables. The fish changes direction in the vicinity of the cable. When the fish has escaped the field, it returns to its previous course, but has then shifted sideways. We wanted to ask the same question concerning AC cables, mostly to be able to rule it out. It was our initial belief that there would not be any effect since the earth s magnetic field does not experience interference from alternating current in the same way, where the magnetic field alternates 50 times a second, explains Håkan Westerberg, one of the project leaders. Cable studies between Öland and the mainland The study was carried out on an AC cable between Öland and the mainland. Four lines with recording buoys were placed across the strait; north, south and directly over the cable. A total of 60 silver eels, tagged with transmitters, were released in two experiments, slightly north of the buoy lines. In this way, it could be measured how long it took for the eels to pass the different buoy lines. All the eels that headed south passed through the area being studied, but the results show that their average speed was significantly lower through the interval where the cable lies. There was a delay of about half an hour, says Håkan Westerberg This is not a huge effect and, as a result, not particularly worrying, rather more intriguing. Something happens at the AC cable, but we do not know what it is down to. It is an interesting observation that should probably be followed up even if it is not done within Vindval. 20

23 21

24 22

25 How wind power affects birds and bats Vindval projects have studied the impact of wind turbines on birds and bats. The collision risk for migrating passerines was found to be slight. Bats hunt insects over the sea, but only when the wind is low. Studies have also been conducted on birds in mountainous habitats, including an ongoing study ahead of a wind farm project in Jämtland. A study within Vindval about how a bird s eye discerns wind farms shows that birds see the wind turbines better than people do, especially at short distances. Bird s ability to discern colour contrasts Despite the fact that visibility varies greatly with weather, time of day, season as well as direction and distance, the wind turbines present choice of colour seems to be well suited to human observers as well as wild birds. 13 The study is the first of its kind to examine the visibility of offshore wind turbines based on the bird s ability to see wind farms. The focus of the study has been on the bird s ability to discern colour contrasts. Researchers have studied both short distances, where the birds risk colliding with the wind turbines, and distances from the coastline. Offshore wind power and bats Studies within Vindval show that bats fly over the sea in wind speeds of up to 10 metres per second, but that the most activity takes place when the force of the wind is lower than 5 metres per second. The larger species of 13 The project is entitled Havsbaserad vindenergi ur ett fågelperspektiv: kraftverkens synlighet för fågelögat (Offshore wind energy from a bird s perspective: a bird s eye view of the turbines). The project leaders are Anders Ödeen, Uppsala University and Olle Håstad, University of Bristol. 23

26 bat can endure stronger winds, but all species prefer light wind. It is mostly during calm weather that bats go out to sea in search of nutriment. 14 Bats do not avoid wind turbines. On the contrary, they often stop off in order to hunt insects that gather around the turbine. Ten bat species have been observed at sea where they go in search of nutriment. Both migratory and stationary species pass or fly out to areas where there are a lot of insects. It has not previously been known that so many bat species regularly hunt insects far out to sea. 15 For example, this can mean that the wind turbines are stopped when the wind speed reaches less than 4 metres per second during that time of year when bat activity is at its greatest. Vary the starting of the rotor blades Insects gather around offshore wind turbines when the winds are light and the weather is fair and bats are tempted to hunt higher up at the same height as the rotor blades, thus increasing the risk of collision. The study also shows that some of the species, at least periodically, use wind turbines as resting places. They can also then become subjected to other risks inside the generator room, for example. In order to avoid collisions, a measure that can be introduced for wind turbines that have already been built and exist within the bats flight path can be to stop the rotor blades turning. For example, this can mean that the wind turbines are stopped when the wind speed reaches less than 4 metres per second during that time of year when bat activity is at its greatest. In South Sweden, this is often during the period between 20 July and 20 September. Since electricity production is negligible during these wind conditions, there will be no economic losses to speak of. The migration route can be registered Research within Vindval shows that when it comes to migratory bats, the most important thing to know is the concentrated migration routes during the autumn. There is knowledge of places around South Sweden s coasts that lie in the highly-frequented migration routes of bats. The most concentrated migration routes can be defined through observations and with automatic registration. 14 Ahlén, Ingemar et al. (2007) Fladdermöss och havsbaserade vindkraftverk studerade i södra Skandinavien (Bats and offshore wind turbines studied in southern Scandinavia). Report No of the Swedish Environmental Protection Agency. 15 Above all, the observations have been made in Kalmarsund, off the Blekinge coast and in Öresund. 24

27 Interview with Jan Pettersson: We now know more about how birds see wind turbines Jan Petterson, researches, within Vindval, about the effects of offshore wind power on small migratory birds and migratory seabirds The risk of birds colliding with wind turbines is very low. Ten to twelve birds a year lose their lives at Utgrunden s turbines and that is when about two million pass through the area every year. So says Jan Pettersson, who, within Vindval, researches about the behaviour of small migratory birds and migratory seabirds in Kalmarsund. At Utgrunden s lighthouse, right in the middle of southern Kalmarsund, there are two marine radar units located. With their help, the height at which small migratory birds and migratory seabirds fly, their avoidance behaviour and where they fly in the strait can be documented. Jan Pettersson has previously shown in a comprehensive study that most seabird flocks veer away from wind turbines in Kalmarsund and Danish studies of offshore wind power also show similar results. 16 Connection between flying height and veering away The height at which small migratory birds and migratory seabirds fly over the open sea during migration and at what distance the flocks veer away from the wind turbines is currently being mapped. The results show that seabird flocks start to veer to the right or the left of Utgrunden s seven wind turbines at a long distance away. The average distance from the turbines that the flocks start to veer away is a full 1.4 kilometres during the day and in good visibility. The average flying height for the same conditions is 65 metres above the sea. Jan Pettersson s study shows that there is a connection between the distance at which the flocks start to veer away and the height at which they fly. When the flocks are flying at a low height, they start to veer away at a longer distance from the rotor blades of the turbines and if they are flying at a higher height, they start to veer away closer to the turbines. A bird s vision is significant I believe that it can have something to do with how birds discern wind turbines through vision. At a longer distance and at a lower flying height, the rotor blades of the turbine become silhouetted against the horizon and constitute a greater contrast with the ultraviolet colour vision that birds have. They become easier to spot. At a higher height, wind turbines are silhouetted against the sea and can be more difficult to discern, says Jan Pettersson. Flying behaviour looks different at night-time. In good visibility, the average flying height is considerably higher than during the day (110 metres) and the flocks start to veer away somewhat later (on average, 413 metres before the turbines). Consideration for migration route The basic facts that have been determined concerning the flying behaviour of migratory birds in Kalmarsund are extremely useful for planning and drawing up environmental consequence descriptions and also for the establishment of wind turbines along other sections of Sweden s coast. It is good that the studies are being conducted on a highly-frequented and extensive migration route as the one at Utgrunden. In comparison, the migration route in the Bay of Gävle is only about a third as extensive as those in Kalmarsund, says Jan Pettersson. 16 Pettersson, Jan (2005) Havsbaserade vindkraftverks inverkan på fågellivet i södra Kalmarsund (The impact of offshore wind farms on bird life in southern Kalmar Sound). Pettersson, Jan (2006) Flyttande små- och sjöfåglar en förstudie med lokalradar i Kalmarsund (Small migratory birds and migratory seabirds a pilot study using local radars in Kalmarsund), Vindval. Danish offshore wind key environmental issues (2006) Danish Energy Authority. 25

28 Birds in mountain areas A research project about how birds in mountain environments are affected by wind turbines is also being conducted within Vindval. Studies are currently being conducted in Oldfjällen in Jämtland where a wind park is being planned at Storrun and Frösörun by Övre Oldsjön. Building is set to start in summer 2008 and the wind park is expected to comprise 12 turbines. Golden eagles and gyrfalcons, which are also considered especially vulnerable to the expansion of wind power in the mountains,are part of a special study using satellite transmitters. The basic data taken from the bird studies shall be used as a comparison for what happens with species richness and how the bird population is affected after the wind park has been erected. 17 Direct observations of migratory birds have been made during the birds migration periods and comprehensive inventories of nesting bird fauna have been carried out during the breeding season within the mountain area that is affected by the wind park. Bird-rich wetlands that are part of a neighbouring Natura 2000 site have also been catalogued as well as the gallinaceous birds of an adjoining forest and mountain area, which have been catalogued with the help of bird dogs. Important to study the grouse population Studies in Norway show that willow grouse are so vulnerable to collisions with wind turbines that the local breeding stock can become affected. Therefore, it is important to study what happens with the grouse population once Storrun s wind park has been put into operation. Golden eagles and gyrfalcons, which are also considered especially vulnerable to the expansion of wind power in the mountains, are part of a special study using satellite transmitters in order to be able to create a map of their movement patterns. Species/specimen-poor bird fauna The results of the studies show that bird fauna in the area is relatively species/specimen-poor, but correspond with other low mountain areas with surrounding wetlands. The existence of species worthy of protection is judged as normal. During territory mapping, 18 territorial species were found where willow warblers, tree pipits, hedge-sparrows, golden plovers, redstarts and willow grouse were the most common species. The direct observations showed that bramblings, meadow pipits, common redpolls and redwings dominate amongst the birds that are in the area during 17 The project is entitled Vindparkers påverkan på fågelfaunan i fjällområden (The impact of wind parks on bird fauna in mountain areas). The project leader is Charlotte Boesson. 26

29 the migration periods. Among the birds of prey and owls that have been observed in the area, golden eagles, hen harriers, rough-legged buzzards, merlins, kestrels, gyrfalcons, short-eared owls and hawk owls can be mentioned. Eagles are more vulnerable After one year of using satellite transmitters on gyrfalcons and two years with transmitters on golden eagles, it appears as if gyrfalcons and young golden eagles stay for a relatively short period of time in the planned wind power area during the young bird s first year, but that they return the following year after passing the winter further south and then spend about five months in the mountains. The study s material on birds of prey is too small to draw any general conclusions. For now, there is too little data about how birds of prey behave in areas with wind parks, however a lot of studies in the US and Norway show that birds of prey prove to be especially vulnerable to wind turbines. There is a reason for assuming that the larger birds of prey, such as eagles, are more vulnerable than the smaller birds of prey, since the ability to manoeuvre decreases with increased size and weight Follestad, A. et al. (2007) Vindkraft og fugl på Smøla (Wind power and birds on Smøla ). NINA report 248. Hunt, W.G et al. (1998) A population study of golden eagles in the Altamont Pass Wind Resource Area: population trend analysis Report to National Renewable Energy Laboratory. 27