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Resource Documents: Alberta (7 items)


Unless indicated otherwise, documents presented here are not the product of nor are they necessarily endorsed by National Wind Watch. These resource documents are shared here to assist anyone wishing to research the issue of industrial wind power and the impacts of its development. The information should be evaluated by each reader to come to their own conclusions about the many areas of debate. • The copyrights reside with the sources indicated. As part of its noncommercial effort to present the environmental, social, scientific, and economic issues of large-scale wind power development to a global audience seeking such information, National Wind Watch endeavors to observe “fair use” as provided for in section 107 of U.S. Copyright Law and similar “fair dealing” provisions of the copyright laws of other nations.

Date added:  December 22, 2009
Alberta, Denmark, Norway, WildlifePrint storyE-mail story

New publications on bats and wind turbines (vol. 90)

Author:  Journal of Mammalogy

Cryan, Paul; and Barclay, Robert. 2009. Causes of Bat Fatalities at Wind Turbines: Hypotheses and Predictions. Journal of Mammalogy 90, 1330-1340.

Abstract. Thousands of industrial-scale wind turbines are being built across the world each year to meet the growing demand for sustainable energy. Bats of certain species are dying at wind turbines in unprecedented numbers. Species of bats consistently affected by turbines tend to be those that rely on trees as roosts and most migrate long distances. Although considerable progress has been made in recent years toward better understanding the problem, the causes of bat fatalities at turbines remain unclear. In this synthesis, we review hypothesized causes of bat fatalities at turbines. Hypotheses of cause fall into 2 general categories proximate and ultimate. Proximate causes explain the direct means by which bats die at turbines and include collision with towers and rotating blades, and barotrauma. Ultimate causes explain why bats come close to turbines and include 3 general types: random collisions, coincidental collisions, and collisions that result from attraction of bats to turbines. The random collision hypothesis posits that interactions between bats and turbines are random events and that fatalities are representative of the bats present at a site. Coincidental hypotheses posit that certain aspects of bat distribution or behavior put them at risk of collision and include aggregation during migration and seasonal increases in flight activity associated with feeding or mating. A surprising number of attraction hypotheses suggest that bats might be attracted to turbines out of curiosity, misperception, or as potential feeding, roosting, flocking, and mating opportunities. Identifying, prioritizing, and testing hypothesized causes of bat collisions with wind turbines are vital steps toward developing practical solutions to the problem.

Download complete article: “Causes of Bat Fatalities at Wind Turbines”

Ahlén, Ingemar; Baagoe, Hans; and Bach, Lothar. 2009. Behavior of Scandinavian Bats during Migration and Foraging at Sea. Journal of Mammalogy 90, 1318-1323.

Abstract. We studied bats migrating and foraging over the sea by direct observations and automatic acoustic recording. We recorded 11 species (of a community of 18 species) flying over the ocean up to 14 km from the shore. All bats used sonar during migration flights at sea, often with slightly lower frequencies and longer pulse intervals compared to those used over land. The altitude used for migration flight was most often 10 m above sea level. Bats must use other sensory systems for long-distance navigation, but they probably use echoes from the water surface to orient to the immediate surroundings. Both migrant and resident bats foraged over the sea in areas with an abundance of insects in the air and crustaceans in the surface waters. When hunting insects near vertical objects such as lighthouses and wind turbines, bats rapidly changed altitude, for example, to forage around turbine blades. The findings illustrate why and how bats might be exposed to additional mortality by offshore wind power.

Download complete article: “Behavior of Scandinavian Bats during Migration and Foraging at Sea”

Baerwald, Erin; and Barclay, Robert. 2009. Geographic Variation in Activity and Fatality of Migratory Bats at Wind Energy Facilities. Journal of Mammalogy 90, 1341-1349.

Abstract. Little is known regarding the migratory behavior of bats, due in part to their elusive nature. Recently, however, fatalities of migratory bats at some wind energy facilities across North America have provided the opportunity and impetus to study bat migration at the landscape level. Using acoustic monitoring and carcass searches, we examined variation in activity levels and fatality rates of bats across southern Alberta, Canada, to determine if bat activity and fatality are concentrated in certain areas or evenly distributed across the landscape. To investigate geographical variation in bat activity, we acoustically monitored activity from 15 July to 15 September 2006 and 2007 at 7 proposed or existing wind energy installations across southern Alberta (~155 km between the most westerly wind energy facility and the most easterly). Activity of migratory bats varied among sites, suggesting that, rather than migrating in a dispersed way across a broad area, bats concentrate along select routes. To investigate variation in bat fatality rates among wind energy installations, we compiled fatality data collected between 2001 and 2007 from 6 wind energy facilities and conducted carcass searches at 3 wind energy installations in 2006 and 2007. Fatality rates differed among the 9 sites, partly due to differences in turbine height, but also due to differences in migratory-bat activity and the interaction between bat activity and turbine height. Our results indicate that bats migrate in certain areas and that measuring migratory activity may allow wind energy facilities to be placed so as to minimize bat fatalities.

Download complete article: “Geographic Variation in Activity and Fatality of Migratory Bats at Wind Energy Facilities”

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Real-time wind production — various regions

Author:  National Wind Watch

World: Current electricity production and consumption of “low-carbon” and “renewable” electricity – click an area for details

Europe: Quarter-hour load, generation, exchange – click on sample graph for other countries

Nordpool: Current production by source type in the Nordic power system (Norway, Sweden, Finland, Estonia, Latvia, Lithuania, Denmark)

Nordpool: Current power flow in the Nordic power system

West Denmark: Electricity prices, consumption, and production today, every 5 minutes

France: Quarter-hour consumption and production

France: Current, weekly, monthly, yearly demand and production

Germany: Quarter-hour net electricity generation

Germany: Quarter-hour wind production in EnBW control area (Baden-Württemberg)

Great Britain: Last 24 hours of generation by fuel type, every 5 minutes

Great Britain: Current, weekly, monthly, yearly demand and production

Ireland: Daily quarter-hour wind generation and system demand

Ireland: Quarter-hour system demand and fuel mix

Spain: 10-minute demand and generation share

Australia: Australian Energy Market Operator (AEMO, southern and eastern Australia): 5-minute and up to past year regional generation and fuel mix

Australia: AEMO grid (National Electricity Market): 5- and 30-minute aregional generation and fuel mix

Alberta: Monthly wind power forecast vs. actual comparison reports

Ontario: Latest hour of generation

Ontario: Daily hourly generation (scroll to bottom of table for wind plant)

Ontario: Hourly generation and other power data

Northwestern USA: Previous week, real-time 5-minute wind generation, Bonneville Power Administration
BPA load and wind generation

California: Daily hourly production, CAISO [click here to download complete report (PDF) from previous day.]
CAISO: yesterday's renewables production

Midwest ISO fuel mix

New England fuel mix (ISO-NE)

Barnstable, Massachusetts: hourly, daily, weekly, monthly, yearly production and consumption of a 100-kW turbine since June 1, 2011 (100% daily generation would be 2,400 kWh)

Scituate, Massachusetts: hourly, daily, weekly, monthly, yearly production and consumption of a 1.5-MW turbine since March 30, 2012 (100% daily generation would be 36,000 kWh)

Mark Richey Woodworking, Newburyport, Massachusetts: hourly, daily, monthly production of a 600-kW turbine since June 2009 (100% daily generation would be 14,400 kWh)

University of Delaware, Newark: current power output (kW) of 2,000-kW turbine

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Date added:  August 27, 2008
Alberta, WildlifePrint storyE-mail story

Barotrauma is a significant cause of bat fatalities at wind turbines

Author:  Baerwald, Erin; d’Amours, Genevieve; Klug, Brandon; and Barclay, Robert

Summary. Bird fatalities at some wind energy facilities around the world have been documented for decades, but the issue of bat fatalities at such facilities – primarily involving migratory species during autumn migration – has been raised relatively recently. Given that echolocating bats detect moving objects better than stationary ones, their relatively high fatality rate is perplexing, and numerous explanations have been proposed. The decompression hypothesis proposes that bats are killed by barotrauma caused by rapid air-pressure reduction near moving turbine blades. Barotrauma involves tissue damage to air-containing structures caused by rapid or excessive pressure change; pulmonary barotrauma is lung damage due to expansion of air in the lungs that is not accommodated by exhalation. We report here the first evidence that barotrauma is the cause of death in a high proportion of bats found at wind energy facilities. We found that 90% of bat fatalities involved internal haemorrhaging consistent with barotrauma, and that direct contact with turbine blades only accounted for about half of the fatalities. Air pressure change at turbine blades is an undetectable hazard and helps explain high bat fatality rates. We suggest that one reason why there are fewer bird than bat fatalities is that the unique respiratory anatomy of birds is less susceptible to barotrauma than that of mammals.

Current Biology, Volume 18, Issue 16, 26 August 2008, Pages R695-R696
doi: 10.1016/j.cub.2008.06.029

Erin F. Baerwald, Genevieve H. d’Amours, Brandon J. Klug, and Robert M.R. Barclay

Department of Biological Sciences, University of Calgary, Calgary, AB Canada T2N 1N4

Download original document: “Barotrauma is a significant cause of bat fatalities at wind turbines

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