The rise of environmental awareness as well as the unstable global fossil fuel market has brought about government initiatives to increase electricity generation from renewable energy sources. These resources tend to be geographically and electrically remote from load centres. Consequently many Distributed Generators (DGs) are expected to be connected to the existing Distribution Networks (DNs), which have high impedance and low X/R ratios. Intermittence and unpredictability of the various types of renewable energy sources can be of time scales of days (hydro) down to seconds (wind, wave). As the time scale becomes smaller, the output of the DG becomes more difficult to accommodate in the DN. With the DGs operating in constant power factor mode, intermittence of the output of the generator combined with the high impedance and low X/R ratios of the DN will cause voltage variations above the statutory limits for quality of supply. This is traditionally mitigated by accepting increased operation of automated network control or network reinforcement. However, due to the distributed nature of RES, automating or reinforcing the DN can be expensive and difficult solutions to implement. The Thesis proposed was that new methods of controlling DG voltage could enable the connection of increased capacities of plant to existing DNs without the need for network management or reinforcement. The work reported here discusses the implications of the increasing capacity of DG in rural distribution networks on steady-state voltage profiles. Two methods of voltage compensation are proposed. The first is a deterministic system that uses a set of rules to intelligently switch between voltage and power factor control modes. This new control algorithm is shown to be able to respond well to slow voltage variations due to load or generation changes. The second method is a fuzzy inference system that adjusts the setpoint of the power factor controller in response to the local voltage. This system can be set to respond to any steady-state voltage variations that will be experienced. Further, control of real power is developed as a supplementary means for voltage regulation in weak rural networks. The algorithms developed in the study are shown to operate with any synchronous or asynchronous generation wherein real and reactive power can be separately controlled. Extensive simulations of typical and real rural systems using synchronous generators (small hydro) and doubly-fed induction generators (wind turbines) have verified that the proposed approaches improve the voltage profile of the distribution network. This demonstrated that the original Thesis was true and that the techniques proposed allow wider operation of greater capacities of DG within the statutory voltage limits.

This report presents the findings of a two-day Rapid Cultural Assessment (RCA) to assess potential impacts to resources important to American Indians from gravel road improvements associated with the Shoshone Mountain phase of the MNS Wind Farm Project on the Nevada Test Site (NTS). The study was conducted by the American Indian Writers Subgroup (AIWS), an official committee of the Consolidated Group of Tribes and Organizations (CGTO). The CGTO is composed of 16 tribes and 3 Indian organizations that have historic or cultural ties to the NTS. The work was facilitated by Dr. Stoffle from the Bureau of Applied Research in Anthropology at the University of Arizona (UofA). Funding was provided by DOE/NV.

Wind turbine noise is a re-emerging issue in the wind industry. As the competition for sites with good wind potential on land is rising, offshore projects in coastal areas seem as a reasonable alternative to onshore. In this context offshore sound propagation is gaining more importance considering that sound will travel over longer distances on water, especially with regard to lower frequencies. Moreover different meteorological conditions that occur on sea may attenuate or enhance sound propagation on water. The prediction tools commonly used by developers are only partially taking these parameters into account. This will be investigated in this thesis.   Hence, different methods for predicting offshore wind turbine noise are going to be assessed. These methods can be divided in two approaches namely algebraic and Partial Differential Equation (PDE) based. The methods evaluated are the ISO 9613-2 standard for outdoor noise prediction, the Danish method and the Swedish method for wind turbines noise estimation over water.   For the PDE based approach, the Helmholtz Equation will be employed in order to examine different meteorological conditions and phenomena occurring over a flat reflecting surface. The experiments with the PDE include the simulation of meteorological conditions with different levels of refraction and changing ground impedance in order to take into account the effect of a shoreline. In addition a meteorological phenomenon called the low-level jet is investigated which is characterised by strong winds at relatively low altitude.   Noise prediction tools used by developers need to be able to consider these effects in order to allow for thorough planning of wind energy projects. Nonetheless, relatively more complex models such as the Helmholtz Equation require experienced users and significant computing time. Further research and development needs to be made in order to promote the wider use of noise prediction methods like the Helmholtz Equation in the wind industry.

The technologies of urban wind turbines have been rapidly developed in recent years, but urban wind turbines have not found a wide application due to the limitations of their designs. The power output of urban wind turbine is significantly affected by urban terrain, which can cause low speed flow with frequent change of its direction. Thus, there is a need for a new wind turbine to meet the requirements of an urban wind turbine. In this study, a novel wind turbine for urban areas was designed and developed. The investigations of the novel urban wind turbine were carried out by using computational fluid dynamic (CFD) simulations and wind tunnel tests. The results from the investigation have shown that the novel wind turbine has a great potential to harvest wind energy in urban areas. A detailed study of effects of each parameter on wind energy concentration of the novel wind turbine was carried out with CFD simulations. According to the simulation results, the shroud structure of the novel wind turbine was modified and the dimensions of the final structure were identified. It was determined that the capability of wind energy concentration of the novel wind turbine shroud has been significantly improved through the structure optimisations. Furthermore, guide vane and impulse turbine were implemented in the novel wind turbine. The flow characteristics through the guide vane was studied and discussed. It was found that the wind flow characteristics can be properly modified by implementing guide vane and the structure of impulse turbine was suitable to be implemented in the novel wind turbine due to the flow characteristic through the guide vane.

This thesis focuses on modelling of wind turbine wakes when they are affected by real complex terrain features, such as hills and forests, and also examines the effect of the rotational momentum imparted to the downstream wake from the rotor blades. Modelling work is carried out using the commercial Computational Fluid Dynamics (CFD) solver FLUENT. Motivation for this project was the fact that there is currently limited knowledge on several issues that affect the operation of a wind farm in a complex terrain environment. Wind developers normally use commercial, easy-to-use software (such as WAsP) to predict the potential wind farm output , which are based on simple linear models to model wakes and wind flow orographic effects and have been calibrated for cases of simple terrain. In cases of complex terrain, they are expected to give errors due to arising non-linearities. After a review of the relevant literature, the chosen CFD procedure is explained. This involves the use of 3-D Reynolds Averaged Navier-Stokes equations using the Reynolds Stress Model for the turbulence closure, in order to account for the anisotropy in atmospheric turbulence. The Virtual Blade Model in FLUENT is demonstrated as a useful tool for modelling the rotor effects without the need of meshing the rotor geometry in detail and avoiding significant computational cost. The approach is initially validated with the widely documented Nibe measurements, which involved full-scale observations of a single wake over at terrain. The model is also tested in the case of a wind turbine operating at the summit of an ideal, Gaussian hill. The wake development is examined in detail and in comparison with another CFD approach. Most notably, a slight divergence is found in the wake path as it evolves downwind. Additionally, the proposed approaches of modelling the neutral atmospheric ow over a real hill and over a forest are validated with full-scale measurements. Ultimately, the work includes the modelling of real wind farms over complex terrain and validating the results with measurements. A coastal complex terrain wind farm is initially examined and results are validated with SCADA measurements and compared with results using the WAsP wind modelling software. Finally, a wind farm over hilly terrain and near forests is also considered and the effect of the forest in the wake is studied. Results are also validated with full-scale measurements.

Increasing the percentage of wind power in the United States electricity generation mix would facilitate the transition towards a more sustainable, low-pollution, and environmentally-conscious electricity grid. However, this effort is not without cost. Wind power generation is time-variable and typically not synchronized with electricity demand (i.e., load). In addition, the highest-output wind resources are often located in remote locations, necessitating transmission investment between generation sites and load. Furthermore, negative public perceptions of wind projects could prevent widespread wind development, especially for projects close to densely-populated communities. The work presented in my dissertation seeks to understand where it’s best to locate wind energy projects while considering these various factors. First, in Chapter 2, I examine whether energy storage technologies, such as grid-scale batteries, could help reduce the transmission upgrade costs incurred when siting wind projects in distant locations. For a case study of a hypothetical 200 MW wind project in North Dakota that delivers power to Illinois, I present an optimization model that estimates the optimal size of transmission and energy storage capacity that yields the lowest average cost of generation and transmission ($/MWh). I find that for this application of storage to be economical, energy storage costs would have to be $100/kWh or lower, which is well below current costs for available technologies. I conclude that there are likely better ways to use energy storage than for accessing distant wind projects. Following from this work, in Chapter 3, I present an optimization model to estimate the economics of accessing high quality wind resources in remote areas to comply with renewable energy policy targets. I include temporal aspects of wind power (variability costs and correlation to market prices) as well as total wind power produced from different farms. I assess the goal of providing 40 TWh of new wind generation in the Midwestern transmission system (MISO) while minimizing system costs. Results show that building wind farms in North/South Dakota (windiest states) compared to Illinois (less windy, but close to population centers) would only be economical if the incremental transmission costs to access them were below $360/kW of wind capacity (break-even value). Historically, the incremental transmission costs for wind development in North/South Dakota compared to in Illinois are about twice this value. However, the break-even incremental transmission cost for wind farms in Minnesota/Iowa (also windy states) is $250/kW, which is consistent with historical costs. I conclude that for the case in MISO, building wind projects in more distant locations (i.e., Minnesota/Iowa) is most economical. My two final chapters use semi-structured interviews (Chapter 4) and conjoint-based surveys (Chapter 5) to understand public perceptions and preferences for different wind project siting characteristics such as the distance between the project and a person’s home (i.e., “not-in-my-backyard” or NIMBY) and offshore vs. onshore locations. The semi-structured interviews, conducted with members of a community in Massachusetts, revealed that economic benefit to the community is the most important factor driving perceptions about projects, along with aesthetics, noise impacts, environmental benefits, hazard to wildlife, and safety concerns. In Chapter 5, I show the results from the conjoint survey. The study’s sample included participants from a coastal community in Massachusetts and a U.S.-wide sample from Amazon’s Mechanical Turk. Results show that participants in the U.S.-wide sample perceived a small reduction in utility, equivalent to $1 per month, for living within 1 mile of a project. Surprisingly, I find no evidence of this effect for participants in the coastal community. The most important characteristic to both samples was the economic benefits from the project – both to their community through increased tax revenue, and to individuals through reduced monthly energy bills. Further, participants in both samples preferred onshore to offshore projects, but that preference was much stronger in the coastal community. I also find that participants from the coastal community preferred expanding an existing wind projects rather than building an entirely new one, whereas those in the U.S.-wide sample were indifferent, and equally supportive of the two options. These differences are likely driven by the prior positive experience the coastal community has had with an existing onshore wind project as well as their strong cultural identity that favors ocean views. I conclude that preference for increased distance from a wind project (NIMBY) is likely small or non-existent and that offshore wind projects within 5 miles from shore could cause large welfare losses to coastal communities. Finally, in Chapter 6, I provide a discussion and policy recommendations from my work. Importantly, I recommend that future research should combine the various topics throughout my chapters (i.e., transmission requirements, hourly power production, variability impacts to the grid, and public preferences) into a comprehensive model that identifies optimal locations for wind projects across the United States.

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. ..."

‘Additive’ goods and services are defined as those that improve with use. They are not naturally rival, or even non-rival, but are “anti-rival.” Information is an example. Information can be made excludable through the use of patents and copyrights, however this does not necessarily lead to socially optimal production and allocation. A more flexible, open access, and decentralized process for the production and allocation of information could improve social welfare. This dissertation describes the challenges and problems with privatizing and restricting access to information and reviews alternative mechanisms for its allocation. Two particular issues at opposite ends of the access spectrum are: (1) strict barriers to private industry databases and (2) quality perception and control of open access information. The first chapter discusses our current system of producing and distributing information and potential ways to stimulate the transition to a new regime. This paper concludes that some of the ideas to seed such a transition include: (1) redefining wellbeing metrics; (2) ensuring the wellbeing of populations during the transition; (3) reducing complexity and increase resilience within institutions; (4) expanding the “commons sector”; and (4) using the internet to remove communication barriers and improve democracy. The second chapter discusses our current system of determining which information to produce, which resources to allocate towards the production of information, and how to distribute that information once produced. The paper concludes that alternative incentive methods, both inside and outside of the market, of producing information and new methods for distributing it to those that can make best use of it, would improve social welfare. These include: (1) prizes; (2) non-monetary incentives; (3) capping salaries; (4) research consortium; and (5) publicly funded research. Chapter 3 explores the difficulty in determining basic energy information under the current proprietary information system using an analysis of the energy return on investment (EROI) of wind energy. It utilizes a meta-analysis of the energy return on investment (EROI) to obtain basic information about the energy inputs and outputs necessary for the manufacturing, installing, operating, and decommissioning of wind turbines. This analysis shows an average EROI for all studies (operational and conceptual) of 25.2 (n=114; std. dev.=22.3). It concludes that making information proprietary severely limits the accuracy of EROI estimates and increases the difficulty of making the best social choices. Chapter 4 explores the perceived credibility of web-based information using an experiment with Encyclopedia Britannica, Wikipedia, and the Encyclopedia of Earth. Compared to Encyclopedia Britannica, both Encyclopedia of Earth and Wikipedia were found to provide a statistically negative perception of credibility. The other factors analyzed (presence or absence of an author, references, a biased sponsor, or an award) contribute to “brand equity” a composite characteristic that takes significant time to develop. The relatively new Encyclopedia of Earth has not yet developed enough brand recognition to affect credibility one-way or the other, but its positive characteristics should help build the brand and credibility over time.

The document reviews the current and projected electricity demand until the year 2030 along with the fuel mix. Several projections based on different agencies were studied in order to understand the trend of fuel mix projected to be used. Clearly, the fuel mix being used or projected is unsustainable. Depletion of fossil fuels, increasing demand and environmental impacts are some of the factors that emphasize the use of Alternative Sources of Electricity. Three of the upcoming Alternative Sources - Solar, Wind and Landfill Gases - are discussed and compared in the document. Based on the comparison, Landfill Gas projects seem to be very favorable, despite the higher costs related with such projects, several advantages over the other two Alternative Sources are discussed in the document. The several advantages of Landfill Gas projects, such as emissions reduction, better power quality, reduction in transmission losses, and several others are discussed in the document

The collateral effects of fossil fuels push humanity to seek solutions to these adversities. Energy efficiency and renewable energies have gone from being almost imaginary concepts to necessary. Several studies have shown that self-sufficiency through photovoltaic systems and wind energy is possible. In addition, it is necessary a storage of the surpluses of both since it increases notably the efficiency of these systems and supposes to the short/medium term a saving of money in the consumer. Due to the mentioned before, the aim of the thesis is to convert a science park located in a cold climate such as Sweden into a complex that does not depend energetically on external sources. For this purpose, a series of data from the park were first collected and then simulated and optimised using the HOMER software for different energy configurations. At the same time, a computer code was created in MatLab to enable the energy produced to be used responsibly. The proposed system consists of PV panels, wind turbines and a battery. Thanks to it, a 64 % renewable fraction is achieved, which means a reduction of 27.45 tons of CO2 per year. In addition, through the energy management system created, the electricity contract is reduced, reducing the purchase of electricity during peak hours. It is concluded that the implementation of both proposed systems contributes significantly to the achievement of the sustainable goals set for 2 030 by the main world leaders, even though a total disconnection with the electrical grid has not been achieved.