Small and Medium size Wind Turbines (SMWTs) can be used for the production of electricity in residential areas, or integrated into hybrid systems, which makes them more attractive in remote areas with difficult access to electricity from the grid. However, many of the SMWTs are installed in locations with low wind speeds, reducing remarkably their annual energy output. Furthermore, SMWTs are typically operated in sub-optimal conditions because they are not completely understood in the real environment. In a design stage, typically a wind tunnel is used to determine the aerodynamic efficiency, but latest research suggests that a turbine in the field behaves differently, especially when the wind is unsteady. Therefore, the aerodynamic performance of a wind turbine tends to be different in the field. Unfortunately, field testing is expensive, and requires long term measurements, especially for small turbine manufacturers. This thesis investigates four topics that could greatly impact the performance of a wind turbine: 1. the wind resource, and how by the spectral modelling of its unsteadiness it is possible to design better turbines and control systems, to adequately react in gusty wind conditions in order to maximise energy harvesting; 2. resource assessment using short-term measurements of wind, to reduce the uncertainty in annual energy production; 3. loss modelling in the generator and power converter to optimise overall efficiency of a wind energy conversion system; and 4. aerodynamic performance identification based on field measurements. On each of these fields, new methods are proposed and validated to improve the existing knowledge. Regarding loss modelling and optimisation, an algorithm to find the global optimum in a system with losses is proposed and tested in an 800 W vertical-axis wind turbine owned by Airborne- Energy Ltd. The experimental data collected in the field, confirms the validity of the approach and its ability to find the optimum despite the high inertia of the turbine, and the unsteadiness of the wind. It is shown that a control algorithm that seeks a global optimum, can increase the overall efficiency of the system, and reduces internal stress on the shaft and power electronics. Finally, as the optimisation algorithm developed in this thesis features the estimation of parameters for a turbine, the processed information can have two positive impacts for further study: detection of system faults and diagnostic of the health-state of the system; and, design specifications, as the manufacturer can have direct inputs of the performance of the turbine to make further improvements for new designs.

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<p>n today's complex environment, clear and sustainable energy is needed to support society development. How to develop the sustainable energy is a core issue in China. Compared with traditional energy, Wind energy has many advantages such as non-fuel cost, less pollution. And wind energy has the absolute advantage that it is worldwide  available. In many courtiers, wind energy has become a major part of their plans for sustainable development. The primary goal of this paper is to analysis advantages and disadvantages of wind power in China and the development potential of wind power in China. In this paper the main methodology is using the information about wind power in China, which is including current situation, development stage, industry development stage, and combining the real case to analysis wind power development potential in China. There are six parts of this paper which are the overview of wind power in china; case description, analysis, conclusions, suggestion, development perspectives and imagination In the first part, the overview of wind power in china, the history of wind power in china, wind resource distribution, wind power development stages, the situation of some key regions, wind  power industry develop stage and also some policies about wind power of Chinese government are discussed. The goal of this part is giving some fundamental information about wind power in China. In the second part, a real case has been described, and according to this case, the construction cost of a wind power plant in China has been discussed. The advantages and disadvantages of wind power are also analyzed based on this case study, such as long-team return, environmental impact, and also some other problem analysis. After the analysis parts, there are the conclusion parts, those parts are about the development perspectives and imagination of wind power in China.</p>

<p>This thesis considers the effect of a large scale wind power introduction into an electricity system and the focus has been on the carbon dioxide emissions. Two different systems were studied, the Swedish and the Danish electricity system. When studying the Swedish electricity system different scenarios were created to see what might happen with the CO₂ emissions with an introduction of a large amount of wind power. The model that was used is based on parameters such as regulating power, transmission capacity, export possibility, and the electricity generation mixes in the Nordic countries. Given that the transmission capacity is good enough, the conclusion is that the carbon dioxide emissions will be reduced with a large scale introduction of wind power. In the Danish electricity system wind power is already introduced to a large extent. The main purpose here was to investigate the development of the CO₂ emissions and if it is possible to decide the actual change in carbon dioxide emissions due to the large scale introduction of wind power. The conclusions to this part are that the CO₂ emissions per kWh produced electricity have decreased since the electricity generation mix has changed but the total amount of CO₂ emissions fluctuates depending on weather, in a dry year less hydro power from Norway and Sweden can be used and more electricity from the fossil fuelled CHPs are generated. It has not been possible to determine the influence of the wind power on the CO₂ emissions.</p>

Thesis (D. Bus. Admin.)--Southern Cross University, 2007. / Title from PDF t.p. (viewed on Mar. 11, 2007). Includes bibliographical references (p. 178-194).

n today's complex environment, clear and sustainable energy is needed to support society development. How to develop the sustainable energy is a core issue in China. Compared with traditional energy, Wind energy has many advantages such as non-fuel cost, less pollution. And wind energy has the absolute advantage that it is worldwide  available. In many courtiers, wind energy has become a major part of their plans for sustainable development. The primary goal of this paper is to analysis advantages and disadvantages of wind power in China and the development potential of wind power in China. In this paper the main methodology is using the information about wind power in China, which is including current situation, development stage, industry development stage, and combining the real case to analysis wind power development potential in China. There are six parts of this paper which are the overview of wind power in china; case description, analysis, conclusions, suggestion, development perspectives and imagination In the first part, the overview of wind power in china, the history of wind power in china, wind resource distribution, wind power development stages, the situation of some key regions, wind  power industry develop stage and also some policies about wind power of Chinese government are discussed. The goal of this part is giving some fundamental information about wind power in China. In the second part, a real case has been described, and according to this case, the construction cost of a wind power plant in China has been discussed. The advantages and disadvantages of wind power are also analyzed based on this case study, such as long-team return, environmental impact, and also some other problem analysis. After the analysis parts, there are the conclusion parts, those parts are about the development perspectives and imagination of wind power in China.

This thesis considers the effect of a large scale wind power introduction into an electricity system and the focus has been on the carbon dioxide emissions. Two different systems were studied, the Swedish and the Danish electricity system. When studying the Swedish electricity system different scenarios were created to see what might happen with the CO2 emissions with an introduction of a large amount of wind power. The model that was used is based on parameters such as regulating power, transmission capacity, export possibility, and the electricity generation mixes in the Nordic countries. Given that the transmission capacity is good enough, the conclusion is that the carbon dioxide emissions will be reduced with a large scale introduction of wind power. In the Danish electricity system wind power is already introduced to a large extent. The main purpose here was to investigate the development of the CO2 emissions and if it is possible to decide the actual change in carbon dioxide emissions due to the large scale introduction of wind power. The conclusions to this part are that the CO2 emissions per kWh produced electricity have decreased since the electricity generation mix has changed but the total amount of CO2 emissions fluctuates depending on weather, in a dry year less hydro power from Norway and Sweden can be used and more electricity from the fossil fuelled CHPs are generated. It has not been possible to determine the influence of the wind power on the CO2 emissions.

To carry out the implementation of some type of renewable energy must do a viability study because the weather conditions at all sites are not the same and therefore the profitability of these technologies would not be good. In case of this project, it is taken into account two of the most important technologies which results are very good around of the world. They are photovoltaic and wind power energy. It will be analysed both kind of energy production from how to produce energy with photovoltaic system and with wind power till how much energy is produced by both ways in one year and whether is this ways to produce electricity is profitable in relation of the investment costs, maintenance, etc...

Growing populations and periodic drought conditions have exacerbated water stress in many areas worldwide. Consequently, it would be valuable to manage both supply and demand of water to fully address water sustainability. Additionally, the inextricable link of water and energy -- energy is required to pump, treat, and distribute water and water is often used in the production of energy -- creates the need to study the use of these resources together. In response to water stress, some municipalities have considered desalination of saline water as a freshwater supply. Unfortunately, desalination requires a sizeable energy investment and causes significant carbon emissions with conventional approaches. However, renewable energy technologies can be paired with desalination to mitigate concern over the environmental impacts of increased energy use. At the same time, desalination can be operated in an intermittent way to match the variable availability of renewable resources. Both wind and brackish groundwater resources are plentiful in the Panhandle region of West Texas, making an integrated wind-powered desalination facility an option for meeting increasing water demands. Integrating wind power and brackish groundwater desalination generates a high-value product (drinking water) from two low-value resources (saline water and wind power without storage). This thesis presents a thermoeconomic, geographic, and operational analysis of an integrated wind-powered reverse osmosis facility treating brackish groundwater in West Texas. The results demonstrate the favorability of the integrated facility under certain economic, geographic, and operating conditions. Also in response to water stress, corporations are becoming increasingly interested in identifying water vulnerabilities in their operational portfolios to minimize physical, reputational, regulatory, and financial risks associated with potential water shortages. The water footprint is one tool available to assess water use, identify vulnerabilities, and guide mitigation strategies. This thesis provides an accounting methodology for water reporting that includes direct water uses and indirect (embedded in energy, services, and products) water uses in the operations. Further, a case study is considered to illustrate the methodology by assessing the water impact of a mixed-use facility in Palo Alto, California. The results demonstrate the importance of considering the indirect water uses, which requires a more exhaustive analysis. / text