Hintergrund "Die ersten in Serie produzierten und kommerziell relevanten Windkraftanlagen (WKA) wurden in den frühen 1990er Jahren aufgestellt. In Deutschland, wie auch in anderen Ländern, wurden in dieser Zeit Förderprogramme wie das Stromeinspeisegesetz aufgelegt und ein zügiger Ausbau der Windenergienutzung setzte ein. So wurden zu Beginn der 1990er Jahre ca. 200 Anlagen mit je bis zu 300 kW pro Jahr installiert und Ende der 1990er Jahre waren es schon bis zu 1500 Anlagen pro Jahr mit je mehr als 1500 kW Leistung. In den 2000ern stieg die Durchschnittsleitung der jährlich installierten Anlagen auf über 2 MW auch wenn sich die Anzahl der Installationen verringerte, siehe Abbildung 1 bei Ender (Ender 2015). Insgesamt sind ca. 3000 Altanlagen entweder schon ca. 20 Jahre im Betrieb und haben damit ihre Konstruktionslebenszeit erreicht oder sind kurz davor. Wie in Abbildung 1 bei Ender (Ender 2015) deutlich zu sehen, steht damit ein rapider Anstieg der von Abriss oder Weiterbetrieb betroffenen Anlagen in den nächsten 5 Jahren bevor. ..."

This thesis presents the results of wind tunnel experiments performed for various model wind turbine arrays. The aim is to understand how siting affects power output. To optimize wind farm efficiency the experiments vary the parameters of the model wind turbines and the layout of the wind turbine array. The parameters include the alignment, height, spacing, and the rotational direction of the model wind turbines. These experiments employ mechanical torque sensors to simultaneously measure the torque and rotor angular velocity, which yields a direct measurement of the fluid mechanical power extracted by the turbine at multiple locations. For a 4 × 3 array, the power is calculated at the center turbine in each of the rows. Variations in wind farm efficiency ranging from 55% to 90% are observed between the 13 different layouts tested. Modifications to the layout of the wind turbine array clearly affects the power output of the wind turbines downstream. The results of such experiments highlight the importance of studying the relationship between wind farm layout and power output.

Amongst the available renewable energy sources, offshore wind energy is having a rapid expansion. Renewable energies are viewed as an environmental benign alternative to the energy production based on fossil fuels, but the emerging development of offshore wind energy has also raised public concern over its potential impact on seabird communities. To assess this impact, seabird distribution and abundance maps are usually included in Strategic Environmental Assessments (SEA) and Environmental Impact Assessments (EIA). Nevertheless few studies have attempted to develop analytical methods to assess quantitatively the potential impacts of offshore wind farms on birds based on seabird distribution data. This PhD study aims to contribute to fill in this gap in the methodological approach. The thesis is a compilation of four studies, two published papers, one submitted manuscript and another ready for submission. These studies focus on different analytical approaches that integrate the spatial and temporal dimension of seabird distribution at large scale and regional and local scale. After presenting these integrative tools I provide practical guidelines for practitioners on how to integrate the tools in the design of SEAs and EIAs. / D’entre totes les fonts d’energia renovable disponibles actualment, l’energia eòlica marina està tenint una ràpida expansió. Les energies renovables es veuen com una bona alternativa per reduir el nostre ús dels combustibles fòssils. El desenvolupament de l’energia eòlica marina, però, també planteja incògnites i preocupació respecte els seus possibles efectes sobre les comunitats d’aus marines. Per avaluar aquest impacte, tant els mapes de distribució com els mapes d’abundància de les aus marines es solen incloure en les avaluacions ambientals estratègiques (AAE) i les avaluacions d'impacte ambiental (AIA). No obstant això, pocs estudis han intentat desenvolupar mètodes analítics per quantificar els impactes potencials dels parcs eòlics marins basats en les dades de distribució i abundància de les aus. Aquest treball de doctorat té com a objectiu contribuir a omplir aquest buit que hi ha a nivell metodològic. La tesi és un recull de quatre estudis, dos articles publicats, un manuscrit enviat i un altre llest per enviar. Aquests estudis es centren en diferents mètodes analítics que integren la dimensió espacial i temporal de la distribució d'aus marines a gran escala i a escala regional i local. Després de presentar aquestes eines d'integració en detall, presento una sèrie de recomanacions i directrius pràctiques sobre la manera òptima d'integrar aquestes eines en el disseny d'EAE i EIA, dirigides principalment a tots aquells experts involucrats en el disseny d’Avaluacions ambientals, tant a nivell estratègic com local. / De entre todas las fuentes de energía renovable disponibles actualmente, la energía eólica marina destaca por su rápida expansión. Las energías renovables están muy bien consideradas como alternativa para reducir nuestro uso de combustibles fósiles. Sin embargo, el desarrollo de la energía eólica marina también plantea incógnitas y cierto grado de preocupación respecto a sus posibles efectos sobre las comunidades de aves marinas. Para evaluar este impacto, se suele incluir mapas de distribución y de abundancia de aves en las Evaluaciones Ambientales Estratégicas (EAE) y las Evaluaciones de Impacto Ambiental (EIA) para este tipo de instalaciones. Sin embargo, pocos estudios han intentado desarrollar métodos analíticos para cuantificar los impactos potenciales de los parques eólicos marinos basados en los datos de distribución y abundancia de las aves. Este trabajo de doctorado tiene como objetivo contribuir a llenar este vacío que existe a nivel metodológico. La tesis es una recopilación de cuatro estudios, dos artículos publicados, un manuscrito enviado y otro listo para enviar. Estos estudios se centran en diferentes métodos analíticos que integran la dimensión espacial y temporal de la distribución de aves marinas a gran escala y a escala regional y local. Tras presentar con detalle estas herramientas de integración, presento una serie de recomendaciones y directrices prácticas sobre la manera óptima de integrar estas herramientas en el diseño de los EAE y EIA, dirigidas principalmente a todos aquellos expertos involucrados en el diseño de Evaluaciones ambientales, tanto a nivel estratégico como local.

Thesis (M.S.)--James Madison University, 2009. / Includes bibliographical references.

High concentrations and fluxes of dissolved organic carbon (DOC) in fluvial systems are associated with the dark brown water colour familiar in many upland, peat-dominated areas and may indicate a depletion of the terrestrial carbon store. The removal of this colour can also be problematic and expensive for water companies as well as affecting the ecological functioning of the water body through factors such as reduced light penetration through the water column. Disturbance resulting from activities such as land use change can also enhance the loss of carbon and this may manifest itself in elevated concentrations and fluxes of DOC from aquatic systems. This thesis describes and explains patterns of change in DOC quantity and quality from the Crosswater, Crosswater of Luce and Tig catchments draining Arecleoch Forest, a peatland in south Ayrshire, Scotland, from 2008 to 2010. This time period incorporates the installation of a 60-turbine wind farm built and operated by Scottish Power Renewables (SPR). Water samples were collected from Arecleoch at different spatial scales ranging from catchments to soil pore water and temporal scales ranging from daily to seasonally. Concentrations of DOC were measured and fluxes estimated at the catchment scale. DOC concentrations from all three catchments exhibited the well-established seasonal pattern with maxima in late August/early September and minima seen in February/March. The Tig catchment experienced the greatest burden of disturbance from the wind farm development and returned the highest DOC concentrations and fluxes. The Crosswater catchment, used as a control site due to its isolation from wind farm activities, had higher DOC concentrations than the Crosswater of Luce throughout the monitoring period possibly due to a greater proportion of forest cover. ii DOC flux ranged from 35.0 g C m-2 yr-1 from the Crosswater of Luce catchment in 2008 to 55.0 g C m-2 yr-1 from the Crosswater in 2009. The Tig catchment was not monitored for the whole period but returned the highest DOC fluxes of the three catchments between January and June 2010 (15.7 g C m-2). These values are considered high for UK peatlands. It is possible to make a tentative estimate of an extra 12 g C m-2 being exported from the Crosswater of Luce in 2009 that may have been a result of wind farm and/or forestry activities in the catchment. At the sub-catchment scale, “hot spots” of high DOC concentrations (up to 113.4 mg L-1) were found during the final survey of headwater streams inside the development area of the wind farm site during construction in August 2010. Further surveys are recommended to assess whether DOC concentrations have decreased since completion of the wind farm. Daily water samples were collected upstream and downstream of turbine 33 during the excavation of the turbine base. DOC concentrations were higher downstream before work began on the turbine base and although the gap between upstream and downstream DOC concentrations increased over the monitoring period, statistical comparisons of these differences before and after the start of excavation work were not significant at the 95 % confidence level. Challenges arose from the practicability of conducting robust research on a construction site and novel approaches to monitoring DOC were developed. Activity scores were used to quantify the effect of peatland disturbance on DOC concentrations at the catchment scale. The results suggest that this approach may have merit but requires comprehensive site records from the developer. The non-linear nature of the individual wind farm development and forestry activities made it impractical to disentangle the impact of each, particularly for forest harvesting. iii Activity scores could, together with other information gathered from site records, be useful to developers as an indicator of the most likely periods for peat disturbance. Knowledge of the differing disturbance potential of the various activities could also provide useful information to feed into the carbon payback calculator. DOC quality was explored using ultraviolet (UV) absorbance, specific UV absorbance (SUVA) and E4/E6 ratios. The latter metric identified changes in the composition of DOC related to disturbance with water samples from areas draining land subject to disturbance having lower E4/E6 ratios indicating a greater degree of humification of the DOC. This research provides one of only three studies to investigate concentrations and fluxes of DOC in water courses draining land subject to disturbance relating to wind farm construction. It is the only study that incorporates a period of time prior to work beginning and takes in the whole of the development phase. In this respect it provides a valuable addition to our understanding of the way in which peatlands respond to land use change and may provide useful tools to assist developers in minimising the impact of their activities on these valuable carbon stores.

Aus der Einleitung: "Der Anteil erneuerbaren Energien in der Energieversorgung soll auch in den kommenden Jahren weiter ausgebaut werden. Dadurch steigt der Bedarf an großen und effizienten Windkraftanlagen (WKA) mit immer höheren Anforderungen an Materialien und Strukturen. Die hohen Belastungen und limitierenden Faktoren in Bezug auf die Lebensdauer solcher Anlagen sind meist dynamisch und abhängig von Strukturschwingungen und Belastungsanregung. Hierzu werden vermehrt Simulationstechniken eingesetzt, die in der Praxis durch den Mangel an genauen Randbedingungen unpräzise sind bzw. als Modell durch Messungen validiert werden müssen. Während typischerweise zur Erfassung von Schwingwegen Beschleunigungsaufnehmer eingesetzt werden, gestaltet sich die Implementierung solcher Messtechnik in drehenden Strukturen meist komplex und aufwändig (Ozbek et al. 2010). Der Einsatz optischer Messtechnik ist im Vergleich einfacher und kann potentiell die Optimierung von Simulationsmodellen unterstützen (Ozbek et al. 2010, Schmidt-Paulsen et al. 2009, 2011)."

Aus der Einleitung: "Der Anteil erneuerbaren Energien in der Energieversorgung soll auch in den kommenden Jahren weiter ausgebaut werden. Dadurch steigt der Bedarf an großen und effizienten Windkraftanlagen (WKA) mit immer höheren Anforderungen an Materialien und Strukturen. Die hohen Belastungen und limitierenden Faktoren in Bezug auf die Lebensdauer solcher Anlagen sind meist dynamisch und abhängig von Strukturschwingungen und Belastungsanregung. Hierzu werden vermehrt Simulationstechniken eingesetzt, die in der Praxis durch den Mangel an genauen Randbedingungen unpräzise sind bzw. als Modell durch Messungen validiert werden müssen. Während typischerweise zur Erfassung von Schwingwegen Beschleunigungsaufnehmer eingesetzt werden, gestaltet sich die Implementierung solcher Messtechnik in drehenden Strukturen meist komplex und aufwändig (Ozbek et al. 2010). Der Einsatz optischer Messtechnik ist im Vergleich einfacher und kann potentiell die Optimierung von Simulationsmodellen unterstützen (Ozbek et al. 2010, Schmidt-Paulsen et al. 2009, 2011)."

Användandet av betong som ersättare för stål vid produktionen av vindkraftverkstorn har ökat den senaste tiden. Betongtorn är betydligt billigare än ståltorn men problem som sprickbildningar, frostsprängningar och följaktligen armeringskorrosion har uppstått bl a på grund av vibrationer från rotorn. I fundamentet i vindkraftverk kan ovan nämnda problem också uppstå och det uppfyller således inte alltid funktionskraven. Det här examensarbetet undersöker möjligheten att eliminera dessa problem genom att använda en sorts högpresterande betong kallad UHPC 2.2 med syntetfiberarmeringen, STRUX. Jämförelser mellan tidigare empiri om högpresterande betong och laborativa tester på UHPC 2.2 visar att den senare är beständigare och ger möjligheter till en större sprickfrihet. Sammanfattningsvis har den högpresterande betongen med fiberarmeringen STRUX visat sig vara en konkurrenskraftig möjlighet på marknaden. / The use of concrete has recently increased as a replacement to steel for the construction of towers for wind power plants. However there are problems such as cracking or frost scaling and finally corrosion of reinforcement, partly due to vibrations caused by the power plants' blades. In the foundation of power plants, the above problems also occur and do not always fulfill the functional requirements. This thesis investigates the possibility to eliminate these problems by using a special kind of high-performance concrete called UHPC 2.2 with synthetic fiber reinforcement, STRUX. When comparing previous empirics about regular concrete with laboratory tests on this high-performance concrete, we find that the later is more durable. In summary, the high-performance concrete with fiber reinforcement STRUX is shown to be a competitive market opportunity.

The Altamont Pass Wind Resource Area (Altamont) near Livermore, California is the oldest and largest wind farm in the United States. It is known as a location of high avian mortality, especially for diurnal raptors such as the Golden Eagle (Aquila chrysaetos). Using the avian monitoring data collected at Altamont for over thirteen years (1998-2003, 2005- 2011), records were analyzed of 134 golden eagle deaths caused by wind turbine collisions. All wind turbines present during the same temporal range were characterized according to turbine variables, and geographic placement characteristics. Values of turbines that killed golden eagles were compared to values of turbnes that did not. It was discovered that turbines that have killed golden eagles (kill turbines) share characteristics that are significantly different from those that have not. Kill turbines are more often situated on lattice structure towers, have larger rotor blade-swept areas, placed in less dense turbine arrays, are further away from the next nearest turbine and are less often placed on top of ridgelines compared to nonkill turbines. Finally, kill turbines are more often situated at the end of a turbine row than are nonkill turbines. The differences between kill and nonkill turbine model, hill slope, tower height, generating capacity, array diversity, row count of turbines and placement in a hill saddle were found to be not significant. These findings support in part, earlier turbine studies at Altamont, but do not concur with all previous findings. The methods used in this study can be applied to any bird species at Altamont and at any wind resource area throughout the world. As the wind industry continues to grow, techniques used in studies such as this are an important tool that can be used to direct wildlife conservation policies.

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