Documents filed under Technology
The Renewable Energy Foundation published this research paper by Dr Gordon Hughes, Professor of Economics at the University of Edinburgh, on the performance over time of wind farms in the United Kingdom and Denmark. The paper can be downloaded by clicking on the link(s) on this page. The UK and Danish data used in the analysis is also available below. The following summarises the results of the research.
The U.S. Recovery Act provided $500 million for research, labor exchange, and job training projects to prepare workers for careers in energy efficiency and renewable energy. The main focus of the Green Jobs training program was to prepare individuals for jobs in Green industry sectors. This report by the U.S. Department of Labor Office of Inspector General Office of Audit found that only 16% of those trained under the program retained their jobs for more than 6 months.
This report was sponsored by the Independent Producers Association of Mountain States. It examined the emissions benefits of renewable energy within an operating grid system and found that the often erratic and unpredictable wind resource resulted in the inefficient operation of coal and gas plants. As a result, the authors report that the temporary reduction in coal or gas to permit wind energy on the system actually raised the level of SO2, NOX and CO2 than would have occurred had less wind energy been generated and the fossil plants permitted to operate as designed.
This important testimony prepared by acoustic expert, Malcolm Swinbanks, explains how NASA researchers calculated the sound levels generated by turbine blades in 1980-1990 and had a comprehensive understanding of wind turbine noise and its effects over 20 years ago.Dr. Swinbanks makes clear that acoustic science involving turbine noise emissions is not new science.
For two decades, the capacity factor of wind power measuring the mean energy delivered by wind turbines has been assumed at 35% of the name plate capacity. Yet, the mean realized value for Europe over the last five years is closer to 21% thus making levelized cost 66% higher than previously thought. This paper, examines the discrepancy and the consequences of the capacity factor miscalculation and some policy recommendations.
This paper documents the results of an in-field test at the Maple Ridge wind energy facility in New York to determine the effectiveness of using an experimental acoustic bat deterrent to reduce bat mortality. The executive summary excerpted below suggests the results were inconclusive. Most bat experts remain unconvinced that acoustic deterrence will be a suitable mitigation approach to reduce bat fatalities at existing turbines.
Europe continues to observe a steady growth in wind generation: from 41 GW of installed power in 2005 to more than 67 GW in 2008. Although wind is a great resource for sustainable power, its unstable behavior is also making the existing power distribution networks less easy to manage.
This report details transmission and operating issues and recommendations for integrating renewable resources on the CAISO Control Grid. The CAISO discusses the gross variations in electric production from wind energy due to the intermittent nature of the resource. During periods of highest demand, the winds drop off.
The November passage of Initiative 937 adds Washington to the states with renewable portfolio standards. Wind-powered generation is a resource of choice in meeting renewable standards, and it has been highly touted for its environmental benefits. Considered in isolation, the environmental benefits of a wind resource are undoubtedly warranted. However, it is misleading to consider wind on an isolated basis—that is, outside of the context of the full power-supply portfolio that is necessary to serve load. In the context of an integrated portfolio, much of the environmental benefit disappears and may even be non-existent as compared with other resource portfolio choices. In particular, a full assessment of the impact of wind resources on the environment necessitates a look at the energy consequences of adding wind-generation to an integrated portfolio in the context of meeting load. Accounting for energy, it is likely that there is no significant environmental difference between a resource portfolio adding wind generation and one adding high-efficiency combined-cycle gas turbines. It is also likely that the wind-based portfolio results in little reduction, if any, in the need for fossil fuels and therefore little reduction in the exposure to their price swings and environmental consequences. That is, the emissions and fossil-fuel impacts of a wind-based portfolio appear little better than a non-wind-based portfolio. Editor's Note: This paper makes a critically important point re. wind's purported environmental benefits, i.e. "...it is misleading to consider wind on an isolated basis—that is, outside of the context of the full power-supply portfolio that is necessary to serve load. In the context of an integrated portfolio, much of the environmental benefit disappears and may even be non-existent as compared with other resource portfolio choices." In short, wind's environmental benefits (if any) will be grid-specific depending on the emissions generated (if any) of the reliable generating source(s) required to back it up.
The objective of this study is to assess the costs that could be incurred by Idaho Power in modifying its operations at the Hells Canyon Complex for “integrating” or incorporating wind energy onto its system. The intermittent and unpredictable nature of wind generation requires a utility to have generating resources available which can increase or decrease generation on short notice in order to keep the interconnected power system balanced. While hydroelectric power plants are well suited for performing this function, there are operational impacts and costs associated with operating Idaho Power hydroelectric plants in a manner that maintains reliability and facilitates integration of energy from wind generation facilities. The issues surrounding the integration of wind generation on interconnected power systems are numerous and complex. This study provides a first step toward understanding those issues.
Rube Goldberg would admire the utter purity of the pretensions of wind technology in pursuit of a safer modern world, claiming to be saving the environment while wreaking havoc upon it. But even he might be astonished by the spin of wind industry spokesmen. Consider the comments made by the American Wind Industry Association.s Christina Real de Azua in the wake of the virtual nonperformance of California.s more than 13,000 wind turbines in mitigating the electricity crisis precipitated by last July.s .heat storm.. .You really don.t count on wind energy as capacity,. she said. .It is different from other technologies because it can.t be dispatched.. (84) The press reported her comments solemnly without question, without even a risible chortle. Because they perceive time to be running out on fossil fuels, and the lure of non-polluting wind power is so seductive, otherwise sensible people are promoting it at any cost, without investigating potential negative consequences-- and with no apparent knowledge of even recent environmental history or grid operations. Eventually, the pedal of wishful thinking and political demagoguery will meet the renitent metal of reality in the form of the Second Law of Thermodynamics (85) and public resistance, as it has in Denmark and Germany. Ironically, support for industrial wind energy because of a desire for reductions in fossil-fueled power and their polluting emissions leads ineluctably to nuclear power, particularly under pressure of relentlessly increasing demand for reliable electricity. Environmentalists who demand dependable power generation at minimum environmental risk should take care about what they wish for, more aware that, with Rube Goldberg machines, the desired outcome is unlikely to be achieved. Subsidies given to industrial wind technology divert resources that could otherwise support effective measures, while uninformed rhetoric on its behalf distracts from the discourse.and political action-- necessary for achieving more enlightened policy.
This paper examines Vermont Public Interest Research Group’s (VPIRG) assertion that by 2015 industrial wind turbines on 8.8% (or 46 miles) of Vermont’s ridgelines above 2500 feet could provide 20% of Vermont’s electricity needs. (1) The examination compares VPIRG’s proposal- which is predicated on Vermont’s average electricity consumption- with the utility industry’s standard for measuring wind energy’s contribution to system reliability and peak demand. i.e. its capacity credit. This measurement concludes that for wind energy to provide the reliable generating capacity to meet 20% of Vermont’s peak demand industrial wind turbines would require 44% - 88% (or 226-451 miles) of Vermont’s ridgeline above 2500’.
Editor's Note: The following are selected excerpts from the Renewable Energy Foundation press release describing this research. The full press release is available via the link below. Using the new research it is now possible to assess how renewable generators up and down the country are performing. This data, published in five online files; Biomass, Hydro, Landfill Gas, Sewage Gas and Windpower, shows that firm generators are producing high load factors with carefully designed resource use and load following. However in the wind sector, far and away the most active of all the technologies at present, results vary enormously due to location. The capacities offshore are encouraging, whilst those onshore are generally only superior in locations very distant from the populations requiring the electrical energy. Although most sites were built on expected capacity factors of around 30%, results include; 19% (approx) capacity factor for the wind turbines at Dagenham, Essex. 9% (approx) capacity factor at the Barnard Castle plant, County Durham. The best performing wind sites are in the north of Scotland, and on Shetland the wind turbines are producing capacity factors of over 50%. Using this analysis of the Ofgem data, researchers have also calibrated a model predicting how a large installed capacity of wind power built across the UK would actually perform. The project used Meteorological Office data to model output for every hour of every January from 1994-2006. The startling results show that, even when distributed UK wide, the output is still highly volatile. The average January power variation over the last 12 years is 94% of installed capacity. It is an uncontrolled variation decided by the weather. The average minimum output is only 3.7% or 0.9GW in a 25GW system. Power swings of 70% in 30 hours are the norm in January. The governments’ expectation is that three quarters of the 2010 renewables target, and the lion’s share of the ‘20% by 2020’ target will be made up of windpower. However, the new research offers predictions which are in keeping with Danish and German empirical experience and demonstrate the need for a broader spread of investment in the renewable sector. The report was commissioned from Oswald Consultancy Limited and funded by donation from the green entrepreneur Vincent Tchenguiz. Campbell Dunford, CEO of REF, said: “This important modelling exercise shows that even with best efforts a large wind carpet in the UK would have a low capacity credit, and be a real handful to manage. This isn’t the best way to encourage China and India to move towards the low-carbon economy. As a matter of urgency, for the planet’s sake, we need to bring forward a much broader range of low carbon generating technologies, including the full sweep of renewables. Wind has a place, but it must not be allowed to squeeze out other technologies that have more to offer.”
This paper provides an assessment of wind power effects on technical and economic performance of today’s electric power systems. While small penetration of wind power is unlikely to cause any qualitative changes, significant percent of wind-generated power will require major rethinking of generation dispatch and automatic generation control, in particular. We summarize technical risks, as well as the economic implications on total cost of providing power to customers. The discussion is presented for both traditional fully regulated utilities and for the portions of the electric power interconnection which are undergoing restructuring. The paper suggests that the ultimate benefit of wind power to the customers will depend to a large extent on how well are today’s operating practices adjusted to make the most out of the available resources, including the intermittent wind power. Moreover, we suggest that an analysis could be done to determine the amount of wind power for a given system beyond which benefits are difficult to capture because of the necessary additional infrastructure cost.
The purpose of this study is to review the performance of wind power in Ontario, with particular attention to the period since the beginning of wind farm operations greater than 20 MW in the spring of 2006. This study comments on the GE Wind Power Integration Study released October 24, 2006 and hereafter referred to as the GE Study. Energy Probe’s study also provides recommendations arising from the observations of the performance results.
Editor's Note This is an opinion piece located in IWA's resource library as it was submitted in pdf. form.
Editor's Note Presented on October 20th during the 2006 Electric Market Forecasting Conference sponsored by EPIS, Inc. this addresses, in part, the issue of whether emissions are reduced with the addition of industrial wind energy. This is a large pdf file (8.55MB) and is available via the weblink below.
Rick Webb's presentation on October 17 at the Energy Virginia conference provides a thought provoking analysis of the costs and benefits of industrial wind energy.