United States

United States

Answers trickle in on bird death report

Formal responses from the California Energy Commission (CEC) to charges that a 2004 report it commissioned on bird deaths in Altamont Pass is deeply flawed in its scientific approach and resulted in the dissemination of inaccurate and inflated fatality rates are due this month. But even before the CEC's official response to the charges, Commissioner John Geesman says he is both "troubled" and "concerned" about missing data and a "botched effort" by the CEC at reviewing the report's controversial conclusions.

Allegations lodged by the wind industry against potential inaccuracies in a report on bird deaths in the Altamont Pass, which was used as the basis for requiring costly seasonal shut downs of wind plant, are to be examined by the California Energy Commission this month

Formal responses from the California Energy Commission (CEC) to charges that a 2004 report it commissioned on bird deaths in Altamont Pass is deeply flawed in its scientific approach and resulted in the dissemination of inaccurate and inflated fatality rates are due this month. But even before the CEC's official response to the charges, Commissioner John Geesman says he is both "troubled" and "concerned" about missing data and a "botched effort" by the CEC at reviewing the report's controversial conclusions.

The charges against the report were publicly levelled a month ago by the California Wind Energy Association (CalWEA) after it had initiated three independent reviews of the way bird mortality data was collected and analysed by the report's authors (Windpower Monthly, November 2006). At the heart of the matter is a significant set of mortality data used in the report that still has not been made publicly available -- even though it played a key role in supporting the report's findings of a far higher rate of bird deaths in Altamont Pass wind farms than any previous report had suggested.

The 2004 report was authored by researchers with BioResource Consultants and prominently cited worldwide. The researchers used two data sets to support their conclusions. One was based on a previous Altamont bird mortality research project conducted for the National Renewable Energy Laboratory (NREL) by BioResource Consultants; the second set was compiled specifically for the 2004 study. Only the second set has been made publicly available. Even though CalWEA identified numerous quality issues in the second set of data, calls for release of the first set have not been heeded.

Al Qaeda involvement

"Unless there's some Al Qaeda involvement with these birds, I don't see why this hasn't been made public," says Geesman. He is also concerned about the CEC's own efforts last year to assess the report's authority. "The first effort at that appears to have been a botched effort and the second effort seems to have gone on for an awful long time without seeing the light of day. I'm troubled by that, and I'm also concerned about the accessibility of data from the 2004 report," he says.

At a CEC meeting last month, Geesman asked the Commission's executive director, BB Blevins, to take up the matter at the next CEC meeting in December. Blevins, meantime, will not comment. What Geesman and others, including CalWEA, want answered is why much of the contents of the first set of data still remains undisclosed. They are also asking why the CEC did not ensure through its contracting terms that all data used to support the report's public findings would be made available.

One expected answer is that the data is not the CEC's to release. The first NREL data set resides only with the researchers and a June, 2006 Public Records Act Request from CalWEA to the CEC echoed this when CEC legal council responded, saying: "BioResources has determined that since the data was collected prior to the Energy Commission contract, it is exempt from any further data submissions. Therefore we are in a dispute situation with our contractor and are unable to provide any data outside of the Energy Commission contract at this time."

Data not withheld

According to the report's authors, K Shawn Smallwood and Carl G Thelander, there is no attempt to keep the data secret. "Data are not being withheld, despite what you have been told," says Thelander. "I have the entire data set here in my office. CalWEA and anyone else are welcome to them when they have been published and our results have gone through a credible peer-review process. We are in the process of releasing the data through standard academic channels."

Thelander also says he has no motivation to release the data directly to CalWEA because, "...that organisation has an established, singular track record of misinterpreting and misusing and miscommunicating data and information provided to them in order to further their clearly biased agenda." The second co-author, Smallwood, expressed similar concerns about the scientific process not being allowed to run its course and that they have both been treated unfairly.

Robert Thresher, director for wind energy at NREL (which does not have the data) acknowledges the researchers' hesitation at releasing their data. "We've encouraged Carl to put it in the public domain but he seems really uncomfortable to release it to CalWEA. He felt his character was being attacked. All of this has been so controversial. And it's not just here. I've heard other avian researchers say their work can be twisted around." But Thresher adds that he feels the best way to get the Altamont controversy cleared up is to have all the data publicly available and subject to a truly independent third party review.

Author's defence

CalWEA suspects that a full release of both data sets may show inconsistencies that could explain the report's higher than expected bird death rates. The report suggests that 4000 of the turbines at the sprawling wind resource area are obsolete and kill an estimated 880 to 1300 eagles, hawks and falcons each year. The authors stoutly defend their results but they do not fully dispute CalWEA's assertion of inconsistent data collection.

Thelander says the statistical and scientific methods used in the previous NREL research were more rigorous than for the second set. The previous research used data collected during March 1998 to September 2001. "We used comparable results from other studies and we document the limitations of doing so -- and that the results should be used with caution," he says. "Those calculated correction factors then incrementally increase the mortality estimates to the higher limits of our estimates, but they are widely accepted by many as being justified and correctly applied to the raw data."

Thelander concedes that the highest estimates have the least amount of statistical reliability or credibility, at least for some reviewers. "But we believe they remain defensible estimates and they may reflect actual kill rates based on the best available information at the time we made them -- but they are estimates, not predictions or facts."

Experimental results

Despite commissioning the 2004 report, the CEC is not among those who "widely accepted" the methods used. In its 2005 Integrated Energy Policy Report, the CEC specifically questions the statistical methods used in the 2004 study, saying it, "represents an important initial effort to craft a methodology to prescribe mitigation measures, but that it should not be misused to form the sole basis for such mitigation measures. Inadequate access to certain turbines, time lapses between surveys, length of survey period, and various extrapolation techniques deprive it of the evidentiary value that the Energy Commission would require as the basis for mitigation measures in a power plant siting. The scientific value of ongoing Energy Commission research into avian mortality prevention should not be jeopardized by misapplication of what are essentially experimental results."

Despite seemingly imperfect statistical modelling and stated doubt from the CEC, the report was widely circulated throughout the US and beyond by anti-wind organisations who used it to attack potential wind projects on the basis of bird deaths. The research also formed part of the basis for legal attacks on operators of wind turbines at Altamont Pass from the Center for Biological Diversity, though these were dismissed in September on technical grounds.

The 2004 report's findings also play a role in ongoing mitigation strategies being deployed by the CEC and Alameda County, where many of the 5600 turbines in the Altamont Pass Wind Resource area are located. These include seasonal shutdowns of turbines, with associated financial losses to the owners which a year ago were estimated at around $9 million a year (Windpower Monthly, November 2005), and repowering efforts to replace smaller fast rotating turbines, which are arguably more dangerous to birds, with newer, slower models.

CalWEA does not dispute the general value of repowering projects or deny there are bird deaths at the facility, but they are particularly concerned about the role the potentially faulty 2004 report is playing in requiring wind farm owners to undertake costly mitigation measures.

Let's move on

Whether the data is released, through what channels it is released, and what is or is not illuminated in December, when the CEC formally deals with the topic, remains to be seen. The CEC's attitude to the 2004 report, however, is perhaps most telling in Geesman's testimony to Blevins during last month's meeting.

"I don't want to, in any way, re-litigate or revisit the Altamont work the Commission did a couple years ago," says Geesman. "And, in fact, the Renewables Committee has implored the participants in our avian guidelines process to move on from Altamont and not allow our discussion of guidelines to be preoccupied by that earlier work."

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