This is a helpful reference document for those interested in understanding the language of the electric utility industry and reliability authorities.

Glossy brochure, including technical specs.

In this report we discuss some recent studies that have occurred in the United States since our previous work [2, 3]. The key objectives of these studies were to quantify the physical impacts and costs of wind generation on grid operations and the associated costs. Examples of these costs are (a) committing unneeded generation, (b) allocating more load-following capability to account for wind variability, and (c) allocating more regulation capacity. These are referred to as “ancillary service” costs, and are based on the physical system and operating characteristics and procedures. This topic is covered in more detail by Zavadil et al. [4].

Courtesty of Eric Rosenbloom, size/technical specifications of wind turbine models currently popular in the USA.

With the exception of some developable wind resource areas in the eastern United States, the wind generation facilities usually interconnect with relatively weak regions of the bulk power networks. With the size of individual wind generation projects growing, this creates difficulties both for designing an appropriate interconnection and in securing transmission capacity to move energy to load centers. The availability of good models and characterizations of wind plant operations are key to analyzing and understanding both of these issues........it should be recognized that the issues confronting transmission providers and wind generation developers are not unique to North America. Organizations around the globe are making substantial investments to move the power industry up the learning curve in this area. In some countries, further growth of the wind industry is contingent upon settling questions related to wind generation impacts on the power system and the availability of appropriate analytical tools and models for making these assessments.....As of the date of this publication, it is clear that the final discussions of interconnection requirements and standards for bulk wind generation are yet to come and may actually be some years into the future. As the previous discussion shows, there is still no consensus on certain technical performance requirements among the various jurisdictional bodies that hold sway on process and reliability requirements for the power industry in the United States.
Editor's Note: This article highlights accurately the critical importance of developing, in light of wind energy's intermittancy, robust interconnection requirements and standards for bulk wind generation to ensure grid stability. While these technical challenges will undoubtedly be met over time, the article does not address the overall cost/benefit equation particularly given wind energy's negligible value as a source of base load capacity.

Eric Rosenbloom writes: "Driving the desire for industrial wind power is the conviction that its development is necessary to reduce the effects of fossil and/or nuclear fuel use. Thus the local impacts of large industrial wind turbine installations are justified by a greater good of healthier air and water, reduction of global warming, and moving away from harmful mining and fuel wars. These are all without question important goals.

While the wind power industry tends to downplay its negative effects, many conservation groups call for careful siting and ongoing study to minimize them. There is debate, therefore, about the actual impacts, but there is none about the actual benefits. Even the most cautious of advocates do not doubt, for example, that "every kilowatt-hour generated by wind is a kilowatt-hour not generated by a dirty fuel."

That may be true for a small home with substantial battery storage, but such a formula is, at best, overly simplistic for large turbines meant to supply the grid. The evidence from countries that already have a large proportion of wind power suggests that is has no effect on the use of other sources. This is not surprising when one learns how the grid works: A rise in wind power simply causes a thermal plant to switch from generation to standby, in which mode it continues to burn fuel."

Author Rosenbloom goes on to take a look at the experience with industrial wind of Ireland, Denmark and Germany and concludes that wind energy's benefits are largely illusory and do not warrant the degradation of rural and wild areas.

BBC Research & Consulting's 2005 report for the National Wind Coordinating Committee that studies 9 wind plant sitings in an effort to identify circumstances that distinguish welcomed projects from projects that were not accepted by communities.

NREL has started to analyze the wind climatology at advanced turbine hub heights based on data measured on existing tall towers in Kansas, Indiana, and Minnesota. The highest measurement level at these towers was 90–110 m. There are two significant findings from the analysis: (1) the difference in wind resource at tall tower sites in the central United States seems to be controlled by the strength of the noctural and southerly winds; and (2) the average wind shear exponent of 50-100 m at tall towers in the central United States is influenced by strong southerly winds and is significantly higher than the 0.143 often used for conservative estimates of the wind resource at turbine hub height.

This working paper is made available by the Resource and Environmental economics and Policy Analysis (REPA) Research Group at the University of Victoria. REPA working papers have not been peer reviewed and contain preliminary research findings. They shall not be cited without the expressed written consent of the author(s).

Editor's Note: The authors’ conclusion regarding ‘effective capacity’, i.e. the measure of a generator’s contribution to system reliability that is tied to meeting peak loads, is that it “is difficult to generalize, as it is a highly site-specific quantity determined by the correlation between wind resource and load” and that ‘values range from 26 % to 0% of rated capacity.” This conclusion is based, in part, on a 2003 study by the California Energy Commission that estimated that three wind farm aggregates- Altamont, San Gorgonio and Tehachpi, which collectively represent 75% of California’s deployed wind capacity- had relative capacity credits of 26.0%, 23.9% and 22.0% respectively. It is noteworthy that during California’s Summer ’06 energy crunch, as has been widely publicized in the press, wind power produced at 254.6 MW (10.2% of wind’s rated capacity of 2,500MW) at the time of peak demand (on July 24th) and over the preceding seven days (July 17-23) produced at 89.4 to 113.0 MW, averaging only 99.1 MW at the time of peak demand or just 4% of rated capacity.

"In response to emerging market conditions, and in recognition of the unique operating characteristics of wind generation, the New York Independent System Operator (NYISO) and New York State Energy Research and Development Authority (NYSERDA) commissioned a joint study to produce empirical information that will assist the NYISO in evaluating the reliability implications of increased wind generation. The work was divided into two phases. Phase 1, Preliminary Overall Reliability Assessment, was completed in early 2004. This initial phase provided a preliminary, overall, screening assessment of the impact of large-scale wind generation on the reliability of the New York State Bulk Power System (NYSBPS).

This document was prepared by General Electric International, Inc. in Schenectady, NY. It is submitted to THE NEW YORK STATE ENERGY RESEARCH AND DEVELOPMENT AUTHORITY (NYSERDA).

Editor's Note:

In the Executive Summary, GE argues that 'imbalance' penalties should not be imposed on wind: "subimbalance penalties should not be imposed on wind generation. Wind projects would need to settle discrepancies between their forecast and actual outputs in the energy balancing market. However, because wind is largely nondispatchable, any additional penalties for imbalance should be eliminated. [emphasis added] The FERC Order 888 allows imbalance penalties to be applied to generators that operate outside of their schedule. As applied in New York, any “overgeneration” can be accepted without payment and any “undergeneration” is priced at the greater of 150% of the spot price or $100/MWh. Strict application of these policies in the MAPS analysis performed would result in the loss of roughly 90% of the wind generation revenue, which would be disastrous to their future development."(page 2.8)