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Intro -- WIND TURBINES PRICE TRENDS AND EXPORT OPPORTUNITIES IN CANADA AND LATIN AMERICA -- WIND TURBINES PRICE TRENDS AND EXPORT OPPORTUNITIES IN CANADA AND LATIN AMERICA -- CONTENTS -- PREFACE -- Chapter 1 U.S. WIND TURBINE EXPORT OPPORTUNITIES IN CANADA AND LATIN AMERICA∗ -- ABSTRACT -- INTRODUCTION -- PRODUCT AND GEOGRAPHIC COVERAGE -- KEY TERMINOLOGY -- U.S. MARKET UNCERTAINTY -- U.S. WIND INDUSTRY EXPANDED IN RESPONSE TO DOMESTIC MARKET GROWTH -- U.S. EXPORTS SIGNIFICANTLY INCREASED DURING 2007-11 -- CANADA COULD BECOME A SIGNIFICANT U.S. EXPORT MARKET -- Overview -- Market -- MARKET COMPETITION -- U.S. EXPORT OPPORTUNITIES -- MEXICAN MARKET PROVIDES OPPORTUNITIES FOR U.S. PRODUCERS -- Overview -- Market -- MARKET COMPETITION -- U.S. EXPORT OPPORTUNITIES -- VIBRANT BRAZILIAN MARKET OFFERS INCONSISTENT U.S. EXPORT OPPORTUNITIES -- Overview -- Market -- MARKET COMPETITION -- U.S. EXPORT OPPORTUNITIES -- AS OTHER LATIN AMERICAN MARKETS EXPAND, EXPORT OPPORTUNITIES ARE INCREASING -- Overview -- Market -- MARKET COMPETITION -- U.S. EXPORT OPPORTUNITIES -- CONCLUSION -- REFERENCES -- End Notes -- Chapter 2 UNDERSTANDING TRENDS IN WIND TURBINE PRICES OVER THE PAST DECADE∗ -- EXECUTIVE SUMMARY -- 1. INTRODUCTION -- 2. WIND TURBINE PRICE TRENDS IN THE UNITED STATES -- 3. WIND TURBINE PRICE DRIVERS -- 3.1. Labor Costs -- 3.2. Warranty Provisions -- 3.3. Turbine Manufacturer Profitability -- 3.4. Increasing Turbine Size and Energy Capture -- 3.5. Raw Materials Prices -- 3.6. Energy Prices -- 3.7. Foreign Exchange Rates -- 4. AGGREGATE IMPACT OF TURBINE PRICE DRIVERS -- 5. LOOKING AHEAD -- APPENDIX A - COMMODITY PRICE TIME SERIES DATA -- Raw Materials Price Data -- Energy Price Data -- APPENDIX B - TABLES 6 AND 7 FROM VESTAS LCA OF 1.65 MW V82 TURBINE (VESTAS 2006B) -- APPENDIX C - EXCHANGE RATE PASS-THROUGH -- REFERENCES -- End Notes

Following an introduction to noise and noise regulation of wind turbines, the problem of adverse health effects of turbine noise is discussed. This is attributed to the characteristics of turbine noise and deficiencies in the regulation of this noise. Both onshore and offshore wind farms are discussed.

Over the last five years an enormous number of wind turbines have been installed in Europe, bringing wind energy into public awareness. However, its further development is restricted mainly by public complaints caused by visual impact and noise. The European Commission has therefore funded a number of research projects in the field of wind turbine noise within the JOULE program. This book presents the most relevant results of these projects. The book addresses all relevant aspects of wind turbine noise, namely: noise reduction, noise propagation, noise measurement, and an introduction to aeroacoustics. It may serve as a first reference in the field of wind turbine noise for researchers, planners, and manufacturers. Fachgebiet: Environmental Engineering Zielgruppe: Research and Development

Both the Netherlands and Denmark started to develop wind energy in the 1970s. Reasons were the oil crisis and the Club of Rome report, which warned of imminent shortages of traditional energy sources like oil and gas. Both countries started this development around 1975 and their governments gave active support. Furthermore, both countries have a comparable wind regime. However, the result of the development of wind energy in each country is very different. In the year 2000, Denmark had a flourishing wind turbine industry, that produced wind turbines for the world market. Furthermore, at the end of the year 2000 the cumulative installed capacity of wind turbines in Denmark was 2,340 MW and wind turbines produced 15% of the electricity demand. In the Netherlands, the situation was far less rosy. Although 10 to 15 wind turbine manufacturers were active on the Dutch market at the beginning of the 1980s, in 2000 only one remained. Furthermore, at the end of the year 2000 only 442 MW of wind turbines had been installed in the Netherlands, the target for the year 2000 having been 2,000 MW. What is the reason for this large difference in the success of the Netherlands and Denmark? This question was the starting point for our research. We investigated whether differences in learning processes in innovation systems during technology development can be the cause for this difference. Our reserach question was: To what extent did the learning processes in the Dutch and the Danish wind turbine innovation systems differ in the period 1973-2000 and what are the consequences of these differences? On the basis of the literature on innovation we identified four kinds of learning: learning by searching (or Research & Development), learning by doing, learning by using and learning by interacting, and the conditions that facilitate these kinds of learning. Next, we investigated the development of wind turbines in the Netherlands and in Denmark and analysed these development with a focus on the learning processes we identified. Our main conclusion is, that in the Netherlands learning by searching much more important than in Denmark, while in Denmark learning by using and learning by interacting were the main learning processes. The strong emphasis on learning by searching in the Netherlands resulted in a large amount of scientific research and a good international position of the Dutch wind energy research. However, the results of this research were hardly used by the wind turbine producers. In Denmark, the market for wind turbines was far larger and better organsied than in the Netherlands. The main reason for this is the early introduction of investment subsidies for wind turbine buyers in Denmark. There were many contacts between the wind turbine owners, the wind turbine producers and the research institute Risø. During these contacts, a lot of knowledge was exchanged between the actors. On the basis of this knowledge, the wind turbine producers developed there turbines further. We argue, that this difference in learning processes in the Dutch and Danish wind turbine innovation systems is an important reason for the difference in success between both innovation systems.

During recent years, wind energy has moved from an emerging technology to a nearly competitive technology. This fact, coupled with an increasing global focus on environmental concern and a political desire of a certain level of diversification in the energy supply, ensures wind energy an important role in the future electricity market. For this challenge to be met in a cost-efficient way, a substantial part of new wind turbine installations is foreseen to be erected in big onshore or offshore wind farms. This fact makes the production, loading and reliability of turbines operating under such conditions of particular interest.

Damage from a lightning strike is the cause of 25% of accidents and breakdowns of wind turbines. To reduce wind turbine damage from lightning and to ensure overall safety around wind turbines, it is important to improve the performance of wind turbines associated with lightning protection and minimize the likelihood of damage to them. The experience of developing countries, actively replenishing the base of windturbines, has led to progress in technologies for the application of countermeasures in the field of wind energy. This article presents the latest trends in technology for reliable operation of wind turbines in thunderstorms.

People who live near wind turbines complain of symptoms that include some combination of the following: difficulty sleeping, fatigue, depression, irritability, aggressiveness, cognitive dysfunction, chest pain/pressure, headaches, joint pain, skin irritations, nausea, dizziness, tinnitus, and stress. These symptoms have been attributed to the pressure (sound) waves that wind turbines generate in the form of noise and infrasound. However, wind turbines also generate electromagnetic waves in the form of poor power quality (dirty electricity) and ground current, and these can adversely affect those who are electrically hypersensitive. Indeed, the symptoms mentioned above are consistent with electrohypersensitivity. Sensitivity to both sound and electromagnetic waves differs among individuals and may explain why not everyone in the same home experiences similar effects. Ways to mitigate the adverse health effects of wind turbines are presented.

Increasing awareness of the issues of climate change and sustainable energy use has led to growing levels of interest in small-scale, decentralised power generation. Small-scale wind power has seen significant growth in the last ten years, partly due to the political support for renewable energy and the introduction of Feed In Tariffs, which pay home owners for generating their own electricity. Due to their ability to respond quickly to changing wind conditions, small-scale vertical axis wind turbines (VAWTs) have been proposed as an efficient solution for deployment in built up areas, where the wind is more gusty in nature. If VAWTs are erected in built up areas they will be inherently close to people; consequently, public acceptance of the turbines is essential. One common obstacle to the installation of wind turbines is noise annoyance, so it is important to make the VAWT rotors as quiet as possible. To date, very little work has been undertaken to investigate the sources of noise on VAWTs. The primary aim of this study was therefore to gather experimental data of the noise from various VAWT rotor configurations, for a range of operating conditions. Experimental measurements were carried out using the phased acoustic array in the closed section Markham wind tunnel at Cambridge University Engineering Department. Beamforming was used in conjunction with analysis of the measured sound spectra in order to locate and identify the noise sources on the VAWT rotors. Initial comparisons of the spectra from the model rotor and a full-scale rotor showed good qualitative agreement, suggesting that the conclusions from the experiments would be transferable to real VAWT rotors. One clear feature observed in both sets of spectra was a broadband peak around 1-2kHz, which spectral scaling methods demonstrated was due to laminar boundary layer tonal noise. Application of boundary layer trips to the inner surfaces of the blades on the model rotor was found to eliminate this noise source, and reduced the amplitude of the spectra by up to 10dB in the region of the broadband peak. This method could easily be applied to a full-scale rotor and should result in measurable noise reductions. At low tip speed ratios (TSR) the blades on a VAWT experience dynamic stall and it was found that this led to significant noise radiation from the upstream half of the rotor. As the TSR was increased the dominant source was seen to move to the downstream half of the rotor; this noise was thought to be due to the interaction of the blades in the downstream half of the rotor with the wake from the blades in the upstream half. It was suggested that blade wake interaction is the dominant noise source in the typical range of peak performance for the full-scale QR5 rotor. Different solidity rotors were investigated by using 2-, 3- and 4-bladed rotors and it was found that increasing the solidity had a similar effect to increasing the TSR. This is due to the fact that the induction factor, which governs the deflection of the flow through the rotor, is a function of both the rotor solidity and the TSR. With a large body of experimental data for validation, it was possible to investigate computational noise prediction methods. A harmonic model was developed that aimed to predict the sound radiated by periodic fluctuations in the blade loads. This model was shown to agree with similar models derived by other authors, but to make accurate predictions very high resolution input data was required. Since such high resolution blade loading data is unlikely to be available, and due to the dominance of stochastic sources, the harmonic model was not an especially useful predictive tool. However, it was used to investigate the importance of the near-field components of the sound radiated by the wind tunnel model to the acoustic array. It was shown that the near-field terms were significant over a wide range of frequencies, and the total spectrum was always greater than that of the far-field component. This implied that the noise levels measured by the acoustic array represented an upper bound on the sound radiated to the far-field, and hence that the latter would also be dominated by stochastic components. An alternative application of the harmonic model, which attempted to determine the blade loading harmonics from the harmonics in the sound field was proposed. This inversion method utilised a novel convex optimisation technique that was found to generate good solutions in the simulated test cases, even in the presence of significant random noise. The method was found to be insensitive at low frequencies, which made it ineffective for inverting the real microphone data, although this was shown to be at least partly due to the limitations imposed by the array size. In addition to the harmonic models, an empirical noise prediction method using the spectral scaling laws derived by \citet*{Brooks_1989} was trialled, and was found to be capable of making predictions that were in agreement with the measured data. The model was shown to be sensitive to the exact choice of turbulence parameters used and was also found to require good quality aerodynamic data to make accurate noise predictions. If such data were available however, it is expected that this empirical model would be able to make useful predictions of the noise radiated by a VAWT rotor. ; This work was supported by the Engineering and Physical Sciences Research Council and Quiet Revolution Ltd.

WIND TURBINE MANUFACTURING IN THE U.S.: DEVELOPMENTS AND CONSIDERATIONS -- WIND TURBINE MANUFACTURING IN THE U.S.: DEVELOPMENTS AND CONSIDERATIONS -- Library of Congress Cataloging-in-Publication Data -- CONTENTS -- PREFACE -- Chapter 1: U.S. WIND TURBINE MANUFACTURING: FEDERAL SUPPORT FOR AN EMERGING INDUSTRY -- SUMMARY -- INTRODUCTION -- WIND TURBINE MANUFACTURING -- Historical Overview -- Demand for Wind Turbines and Components -- Wind Turbine Suppliers -- International Manufacturers Dominate Wind Turbine Manufacturing -- U.S. Market Attracts More Foreign Wind Turbine Manufacturers

The main objective of IEA R&D Wind Annex XVII - Database on Wind Characteristics - has been to provide wind energy planners, designers and researchers, as well as the international wind engineering community in general, with a source of actual wind fielddata (time series and resource data) observed in a wide range of different wind climates and terrain types. Connected to an extension of the initial Annex period, the scope for the continuation was widened to include also support to the international windturbine standardisation efforts. The project partners are Sweden, Norway, U.S.A., The Netherlands and Denmark, with Denmark as the Operating Agent. The reporting of the continuation of Annex XVII falls in two separate parts. Part one accounts in detailsfor the available data in the established database bank, and part two describes various data analyses performed with the overall purpose of improving the design load cases with relevance for to wind turbine structures. The present report constitutes thesecond part of the Annex XVII reporting. Both fatigue and extreme load aspects are dealt with, however, with the main emphasis on the latter. The work has been supported by The Ministry of Environment and Energy, Danish Energy Agency, The NetherlandsAgency for Energy and the Environment (NOVEM), The Norwegian Water Resources and Energy Administration (NVE), The Swedish National Energy Administration (STEM) and The Government of the United States of America.