Avian collision risk models for wind energy impact assessments

With the increasing global development of wind energy, collision risk models (CRMs) are routinely used to assess the potential impacts of wind turbines on birds. We reviewed and compared the avian collision risk models currently available in the scientific literature, exploring aspects such as the calculation of a collision probability, inclusion of stationary components e.g. the tower, angle of approach and uncertainty. 10 models were cited in the literature and of these, all included a probability of collision of a single bird colliding with a wind turbine during passage through the rotor swept area, and the majority included a measure of the number of birds at risk. 7 out of the 10 models calculated the probability of birds colliding, whilst the remainder used a constant. We identified four approaches to calculate the probability of collision and these were used by others. 6 of the 10 models were deterministic and included the most frequently used models in the UK, with only 4 including variation or uncertainty in some way, the most recent using Bayesian methods. Despite their appeal, CRMs have their limitations and can be ‘data hungry’ as well as assuming much about bird movement and behaviour. As data become available, these assumptions should be tested to ensure that CRMs are functioning to adequately answer the questions posed by the wind energy sector.     

Differential recovery of habitat use by birds after wind farm installation: A multi-year comparison

Onshore wind farms remain one of the most widely used technologies for the production of renewable energy. These are known to affect birds through disturbance or collision. Most research focus on the impact of wind farms on raptors or other large bird species, especially those of conservation concern. However, limited information exists on the effect of wind farms on small birds. Recovery of large versus small bird populations impacted by wind farms is also largely unstudied. A reason for this is the lack of long-term datasets based on standardized, systematic assessments. We monitored birds in the vicinity of a wind farm in an upland habitat in southern Spain (Malaga province), immediately after installation and 6.5 years post-construction. During both study periods, we observed 11 raptor and 38 non-raptor species (including 30 passerines). We found differences in recovery rates between raptors and non-raptors. Raptors showed an upturn in numbers but non-raptor abundance fell significantly.Greater attention should be paid to the recovery of wildlife after initial impact assessments than at present. This study confirms that regulatory authorities and developers should consider the likely impacts of wind farms on small bird populations. Mitigation measures focused particularly on non-raptor species should be considered and implemented as a means to reduce these negative effects.     

东沙沙洲离岸潮间带风电场建设对鸟类的影响

对东沙沙洲离岸潮间带风电场的建设给鸟类造成的影响进行了调查。分析表明,噪声对东沙沙洲迁徙鸟类影响不大;光对夜间迁徙鸟类造成一定的影响;风机对候鸟迁徙影响不大,少数低飞候鸟可能存在撞机风险;风机基础和人工岛的永久占地造成的直接生物量损失为3.2 t/a,总计损失约64万元;风电场建设将使东沙沙洲鸟类栖息地面积减少81.5 km2,约占总栖息地面积的13.9%,但风机对鸻鹬类等中小型涉禽、水鸟的觅食影响不大,风电场区域仍可作为这些鸟类的觅食地。在影响分析的基础上提出了设计、施工、运营阶段相应的防范措施。     

Changes in bird species composition after a wind farm installation: A case study in South America

Facing the growing demand for renewable energy sources, the use of wind energy has been significantly increasing worldwide. Wind farms are known to present low environmental impact and their impact on bird fauna has been the most studied and discussed. In this study, we evaluated the composition of bird communities and changes in land use during three phases of wind farm development: pre-construction, construction and operation. Secondary data was obtained on bird communities, provided by the wildlife monitoring report submitted to the state environment agency of Rio Grande do Sul, Brazil. The total number of species recorded for all phases of wind farm construction was 163 species. One hundred species were present during all phases, and 20 were recorded during at least two phases, 32 species were exclusive to the pre-construction phase, four species were recorded only during the construction phase and seven recorded during the operation phase. The evaluation of bird community structure revealed that the pre-construction phase differed from the 4 years of operation, indicating that an impact on bird species' composition is evident, but more detailed and longer surveys are needed to confirm this trend. The bird community responded to landscape changes, mainly due to the reduction of native and exotic forest cover, in areas affected by wind farms installation and operation, in both, species' composition and environmental guilds. Analysis of secondary data allows us to evaluate which changes may have resulted from the implantation of the wind energy industry to the regional bird fauna, and our findings demonstrates tha the changes associated with the construction and operation of this wind farm have negatively affected the bird community.     

海洋风电场水下噪声评估与管理研究

总结了海洋风电场建设中水下噪声的主要类型与声学特性,基于国内外水下噪声对海洋生物影响的最新研究成果,分析了海洋风电场噪声对生态环境的可能影响,尤其是近岸海域海洋风电施工期冲击式打桩噪声对海洋生物的影响。在此基础上,参考《海上风电工程环境影响评价技术规范》的相关内容,提出了海洋风电场水下噪声测量与评估方法,以及控制与降低噪声的措施建议。     

Life-cycle impacts of wind energy development on bird diversity in Norway

While wind energy remains a preferred source of renewable energy, understanding the full spectrum of impacts are vital to balance climate-related benefits against their costs to biodiversity. Environmental impact assessments often fail to assess cumulative effects at larger spatial scales. In this respect, life cycle assessments are better suited, but have to date mainly focused on greenhouse gas emissions and energy accounting. Here, we adapt a recent global life-cycle impact assessment (LCA) methodology to evaluate collision, disturbance and habitat loss impacts of onshore wind energy development on bird species richness in Norway. The advantage of a local model for Norway is that it enables employing species distribution models to more accurately estimate the potential distribution area of species. This facilitates more realistic site- and species-specific assessments of potential impacts within a local scale but excludes habitat ranges outside Norway. Furthermore, a new characterization factor was developed for potential barrier effects. Larger onshore wind-power plants overall had greater site-specific potentially disappeared fractions (PDF) of species, while smaller plants were less efficiently located with greater impacts per GWh. Overall, Norwegian wind-power plants were sited least efficiently (PDF/GWh) regarding indirect habitat loss (2.186 × 10⁻⁹) and disturbance (1.219 × 10⁻⁹), followed by direct habitat loss (0.932 × 10⁻⁹), and finally collisions (0.040 × 10⁻⁹) and barriers (0.310 × 10⁻⁹). Vulnerability differed among bird groups with seabirds, raptors and waterfowl emerging as the most impacted groups (e.g. 5.143 × 10⁻⁹, 3.409 × 10⁻⁹ and 3.139 × 10⁻⁹ PDF/GWh for disturbance, respectively); highlighting the sympatric distribution of their habitats and the majority of Norway's onshore wind-power plants. Current practice has not succeeded in avoiding sites with higher impacts for birds, fuelling conflicts surrounding environmental concerns of onshore wind energy development in Norway. Operative LCA models can help decision-makers assessing localized life-cycle environmental impacts to support environmental-friendly wind energy production in specific regions.     

Accuracy of wind farm visualisations: The effect of focal length on perceived accuracy

Wind energy has been the fastest growing renewable energy technology for more than a decade. However, the visual impacts of wind farms are still one of the most controversial effects of wind energy development. Photomontage visualisations are frequently used in Visual Impact Assessments² (VIA) to give a sense of scale of the proposed development. Yet visualisations in VIAs are often perceived to underestimate the scale and magnitude of the visual impact of wind turbines. The aim of this multiphase mixed methods study is to explore the perceived accuracy of images that represent the visual impacts of both onshore and offshore wind farms. Field visits and data from a public survey are used to assess the accuracy of visualisations and to examine the effect of camera lens focal length on perception of scale of wind turbines. Results show that panoramic photomontages are perceived as the least accurate, while images taken at 75 mm focal length in full frame format are perceived as the most accurate form of representation of the scale and visual impact of wind turbines. These findings imply that the panoramic visualisation technique, which has been used for decades to predict the scale of wind turbines in VIAs, is ineffective in predicting accurately the visual impact of wind farms, and an alternative predictive technique is needed. For wind farm visualisations the use of 75 mm full frame image format is recommended in order to improve the accuracy, enable better informed decision making and avoid the loss of credibility of visualisations and VIAs.     

Approaching population thresholds in presence of uncertainty: Assessing displacement of seabirds from offshore wind farms

Assessment of the displacement impacts of offshore wind farms on seabirds is impeded by a lack of evidence regarding species-specific reactions to developed sites and the potential ecological consequences faced by displaced individuals. In this study, we present a method that makes best use of the currently limited understanding of displacement impacts. The combination of a matrix table displaying the full range of potential displacement and mortality levels together with seasonal potential biological removal (PBR) assessments provides a tool that increases confidence in the conclusions of impact assessments. If unrealistic displacement levels and/or mortality rates are required to equal or approach seasonal PBRs, this gives an indication of the likeliness of adverse impacts on the assessed population. This approach is demonstrated by assessing the displacement impacts of an offshore wind farm cluster in the German North Sea on the local common guillemot (Uria aalge) population.     

Modeling and simulation of offshore wind farm O&M processes

This paper describes a holistic approach to operation and maintenance (O&M) processes in the domain of offshore wind farm power generation. The acquisition and process visualization is followed by a risk analysis of all relevant processes. Hereafter, a tool was designed, which is able to model the defined processes in a BPMN 2.0 notation, as well as connect and simulate them. Furthermore, the notation was enriched with new elements, representing other relevant factors that were, to date, only displayable with much higher effort. In that regard a variety of more complex situations were integrated, such as for example new process interactions depending on different weather influences, in which case a stochastic weather generator was combined with the business simulation or other wind farm aspects important to the smooth running of the offshore wind farms. In addition, the choices for different methodologies, such as the simulation framework or the business process notation will be presented and elaborated depending on the impact they had on the development of the approach and the software solution.     

大丰风电场建设对盐城自然保护区的生态影响分析

研究了大丰风电场一期、二期工程对盐城沿海湿地珍禽国家级自然保护区的生态影响.结果表明,在自然保护区实验区内建风电场会改变自然保护区生态结构和功能,使生物量减少,鸟类栖息地丧失,物种多样性下降,景观破碎化.提出了对策措施,以降低由于风电场的建设对自然保护区造成的生态影响.     

Can Offshore Wind Energy Be a Lever for Job Creation in France? Some Insights from a Local Case Study

The French government has launched three separate calls for tender in July 2011, March 2013, and December 2016 to install 3.5 GW of offshore wind. In addition to contributing to the fulfillment of environmental commitments, the deployment of offshore wind energy is expected to be a lever for economic development. To assess gross economic impacts, mainly in terms of job creation, we built a regional input-output model of the wind farm off Saint-Brieuc located in the region of Brittany, north-western France. Our model indicates that the project will have positive effects on Brittany’s economy. In particular, during the investment phase, the wind farm is expected to lead to €0.38 M/year/MW of added value and 6.03 full-time equivalent (FTE) jobs/year/MW. During the operation and maintenance (O&M) phase, the model predicts the generation of €0.15 M/year/MW of added value and 1.02 FTE jobs/year/MW. These results imply that the project will increase Brittany’s GDP slightly by 0.22 and 0.09% during the investment and O&M phases, respectively. Results also show that out of total wealth created in France, 38 and 66% will be created in Brittany as well as 32 and 51% of employment during respectively investment and O&M phases. A comparative analysis highlights in particular that economic impacts are generally stronger during the investment phase. It also demonstrates that the magnitude of economic impacts depends on the proportion of local industries in the supply chain. Policy implications of our model stress the need to revise the economic, technological, regulatory, and social frameworks within which the offshore wind industry currently operates in France to establish the conditions necessary for its development.     

Assessing the wildlife habitat value of New England salt marshes: II. Model testing and validation

We tested a previously described model to assess the wildlife habitat value of New England salt marshes by comparing modeled habitat values and scores with bird abundance and species richness at sixteen salt marshes in Narragansett Bay, Rhode Island USA. As a group, wildlife habitat value assessment scores for the marshes ranged from 307-509, or 31-67% of the maximum attainable score. We recorded 6 species of wading birds (Ardeidae; herons, egrets, and bitterns) at the sites during biweekly survey. Species richness (r (2)=0.24, F=4.53, p=0.05) and abundance (r (2)=0.26, F=5.00, p=0.04) of wading birds significantly increased with increasing assessment score. We optimized our assessment model for wading birds by using Akaike information criteria (AIC) to compare a series of models comprised of specific components and categories of our model that best reflect their habitat use. The model incorporating pre-classification, wading bird habitat categories, and natural land surrounding the sites was substantially supported by AIC analysis as the best model. The abundance of wading birds significantly increased with increasing assessment scores generated with the optimized model (r (2)=0.48, F=12.5, p=0.003), demonstrating that optimizing models can be helpful in improving the accuracy of the assessment for a given species or species assemblage. In addition to validating the assessment model, our results show that in spite of their urban setting our study marshes provide substantial wildlife habitat value. This suggests that even small wetlands in highly urbanized coastal settings can provide important wildlife habitat value if key habitat attributes (e.g., natural buffers, habitat heterogeneity) are present.     

Assessing the regional impacts of increased energy maize cultivation on farmland birds

The increasing cultivation of energy crops in Germany substantially affects the habitat function of agricultural landscapes. Precise ex ante evaluations regarding the impacts of this cultivation on farmland bird populations are rare. The objective of this paper was to implement a methodology to assess the regional impacts of increasing energy maize cultivation on the habitat quality of agricultural lands for farmland birds. We selected five farmland bird indicator species with varying habitat demands. Using a crop suitability modelling approach, we analysed the availability of potential habitat areas according to different land use scenarios for a real landscape in Northeast Germany. The model was based on crop architecture, cultivation period, and landscape preconditions. Our results showed that the habitat suitability of different crops varied between bird species, and scenario calculations revealed an increase and a decrease in the size of the potential breeding and feeding habitats, respectively. The effects observed in scenario 1 (increased energy maize by 15 %) were not reproduced in all cases in scenario 2 (increased energy maize by 30 %). Spatial aggregation of energy maize resulted in a negative effect for some species. Changes in the composition of the farmland bird communities, the negative effects on farmland bird species limited in distribution and spread and the relevance of the type of agricultural land use being replaced by energy crops are also discussed. In conclusion, we suggest a trade-off between biodiversity and energy targets by identifying biodiversity-friendly energy cropping systems.     

Environmental impacts of decommissioning: Onshore versus offshore wind farms

Increasing concerns over climate change have prompted rapid growth of renewable energy over the past few decades, particularly wind energy. However, as the installation of wind farms rises, so will the need for decommissioning and analysis of the environmental impacts associated with decommissioning. This paper investigates how Environmental Impacts Assessments (EIA) identify, estimate and manage potential impacts of decommissioning. EIAs from 12 onshore and offshore windfarms consented between 2009 and 2014 in England and Scotland were analysed and compared. Attributes of these windfarms' Environmental Statements (ES) were scored under six categories: decommissioning in EIA stages, definitions of decommissioning, amount of analysis, depth of analysis, impacts identified, and proactive planning. Onshore windfarms generally tended to investigate the impacts of decommissioning less than offshore windfarms, even those which gained consent in the same year. The investigation of the impact of decommissioning improved for windfarms consented in the latter years of the study period. Across the ESs there was a lack of analysis of potential impacts from decommissioning in their own right: not simply as a reversal of the construction process. The impacts of different end of life scenarios were not analysed in any of the ESs studied. There is evidence to suggest the presence of windfarms, especially offshore, could in some cases be environmentally beneficial for certain species. However, the ecological impact of removing offshore structures at the end of life is unknown and is currently not investigated nor predicted in EIAs. Understanding the potential implications of full or partial removal of marine structures, or alternatives to decommissioning, could ensure that appropriate mitigation is considered at an early stage by both developer and consenting authority. That being said, it is also important to update the assessment of potential impacts over the life of the project as more information on the environment is gathered and end of life plans develop.     

Land suitability assessment for wind power plant site selection using ANP-DEMATEL in a GIS environment: case study of Ardabil province,Iran

Wind energy is a renewable energy resource that has increased in usage in most countries. Site selection for the establishment of large wind turbines, called wind farms, like any other engineering project, requires basic information and careful planning. This study assessed the possibility of establishing wind farms in Ardabil province in northwestern Iran by using a combination of analytic network process (ANP) and decision making trial and evaluation laboratory (DEMATEL) methods in a geographical information system (GIS) environment. DEMATEL was used to determine the criteria relationships. The weights of the criteria were determined using ANP and the overlaying process was done on GIS. Using 13 information layers in three main criteria including environmental, technical and economical, the land suitability map was produced and reclassified into 5 equally scored divisions from least suitable to most suitable areas. The results showed that about 6.68 % of the area of Ardabil province is most suitable for establishment of wind turbines. Sensitivity analysis shows that significant portions of these most suitable zones coincide with suitable divisions of the input layers. The efficiency and accuracy of the hybrid model (ANP-DEMATEL) was evaluated and the results were compared to the ANP model. The sensitivity analysis, map classification, and factor weights for the two methods showed satisfactory results for the ANP-DEMATEL model in wind power plant site selection.     

Landscape Correlates of Breeding Bird Richness Across the United States Mid-Atlantic Region

Using a new set of landscape indicator data generated by the U.S.EPA, and a comprehensive breeding bird database from the National Breeding Bird Survey, we evaluated associations between breeding bird richness and landscape characteristics across the entire mid-Atlantic region of the United States. We evaluated how these relationships varied among different groupings (guilds) of birds based on functional, structural, and compositional aspects of individual species demographics. Forest edge was by far the most important landscape attribute affecting the richness of the lumped specialist and generalist guilds; specialist species richness was negatively associated with forest edge and generalist richness was positively associated with forest edge. Landscape variables (indicators) explained a greater proportion of specialist species richness than the generalist guild (46% and 31%, respectively). The lower value in generalists may reflect finer-scale distributions of open habitat that go undetected by the Landsat satellite, open habitats created by roads (the areas from which breeding bird data are obtained), and the lumping of a wide variety of species into the generalist category. A further breakdown of species into 16 guilds showed considerable variation in the response of breeding birds to landscape conditions; forest obligate species had the strongest association with landscape indicators measured in this study (55% of the total variation explained) and forest generalists and open ground nesters the lowest (17% of the total variation explained). The variable response of guild species richness to landscape pattern suggests that one must consider species' demographics when assessing the consequences of landscape change on breeding birds.     

Relationships of Human Disturbance, Bird Communities, and Plant Communities Along the Land-Water Interface of a Large Reservoir

We examined the relationships of humanactivity, bird communities, and plant communities along theland-water interface of Lake Texoma, a large human-madereservoir on the Texas-Oklahoma border. Measurements ofhuman activity, plant surveys, and bird surveys wereperformed at 40 paired transects, one with humandisturbance, the other undisturbed. Both principalcomponents and correspondence analyses of bird-survey dataseparated disturbed sites from paired undisturbed sites, andtypical disturbance-tolerant species from those lesstolerant of human activity. Compared to undisturbed sites,disturbed sites tended to have more individual birds persurvey, pavement, and mowed lawns, and less canopy,vegetation volume, and vegetation vertical diversity. Aprincipal components analysis of quantitative disturbancemeasurements revealed that most bird and plant measures werehighly correlated with the first disturbance component. However, the correlation between birds and human activitywas much stronger than that between birds and plants, orbetween plants and disturbance. Our data suggest that bird-species composition is regulated more by human activity thanby plant-community composition. Also, in this system, birdcommunities are a better choice than plant communities toindex the effect of human disturbance. To maintain regionaldiversity of both birds and plants, undisturbed areas shouldbe maintained around reservoirs.     

Biodiversity and bird surveys in Finnish environmental impact assessments and follow-up monitoring

Environmental Impact Assessments (EIAs) that are applied in the planning phases of large land-use and construction projects are aimed at aiding decision-making and mitigating significant environmental impacts. In light of the global biodiversity crisis, conducting high-quality biodiversity impact assessments is important, as biodiversity information, among other factors, has the potential to influence how projects will be implemented in the end. We investigated the biodiversity and bird surveys conducted and the number of bird species of conservation concern in peat extraction and wind farm projects to which an EIA was applied to in 1995–2016 in Finland and compared whether these factors differed between the project types and between implemented and unimplemented projects. We also studied the availability of follow-up monitoring data of biodiversity impacts within the two project types. The number of nationally threatened breeding birds was significantly lower in implemented than in unimplemented peat extraction projects. The overall probability of being implemented was significantly negatively associated with the year the EIA began for both project types. All permitted peat extraction projects and 22% of wind farm projects conducted post-construction biodiversity monitoring; however, only some projects enabled before-after comparisons. Our results are in line with earlier findings that demonstrate the difficulty of showing the direct impacts of biodiversity information on EIA decision-making and to what extent it is related to project approval or rejection. The role of follow-up monitoring in the EIA and project development could also be strengthened.     

Grouping and representativeness of monitoring stations based on wind speed and wind direction data in urban areas of Japan

Data on wind speed and wind direction from 27 air pollution monitoring stations in an urban area of Japan were analyzed and studied for the future assessment of the urban heat island phenomenon. A cluster analysis clarified the regionality of the wind speed and wind direction. In the study area, land and sea breeze developed and controlled the wind direction. On the other hand, the mountain and valley wind should be studied to determine their typical behavior.