Danish Study Is Boost for Wind Farms


In the most comprehensive scientific analysis on offshore wind farms to date, a Danish government report released last week found little or no environmental impacts from the world's two largest offshore projects.

The findings are significant for the Nantucket Sound wind farm proposal because they address many of the environmental concerns raised about Cape Wind - the first offshore project proposed in the United States.

"Danish experience from the past 15 years shows that offshore wind farms, if placed right, can be engineered and operated without significant damage to the marine environment and vulnerable species," the report said in its executive summary. "Under the right conditions, even big wind farms pose low risks to birds, mammals and fish."

Authored by Danish energy and environmental government agencies, along with power companies that own the two offshore projects, the 140-page report represents the culmination of eight years of studies dating back prior to construction and continuing through the current year. Government scientists presented their findings last week at a conference in Denmark attended by wind energy leaders from around the world, including top executives from both Cape Wind and its chief opponent, the Alliance to Protect Nantucket Sound.

Also in attendance were officials from the Minerals Management Service, the environmental agency within the U.S. Department of Interior which has lead regulatory authority over offshore wind farms in this country and is currently reviewing the Cape Wind proposal. Dr. Rodney Cluck, Cape Wind project manager for the Minerals Management Service, praised the Danish report this week and said it provided concepts and methodology that will prove useful to the agency's ongoing review. But he also stressed the need for site-specific Nantucket Sound studies in the Cape Wind environmental impact statement, scheduled for release later this winter.

"For our use here in the United States, the report and its findings are very important. It adds to our overall knowledge and understanding of offshore wind developments," Mr. Cluck said. "We still have to study each individual area, to know the particular species and their possible impacts. But scientifically, the report was very well done."

The report, titled Danish Offshore Wind: Key Environmental Issue, focused on two large offshore wind farms built within the past few years - the 80-turbine Horns Rev project, which is located nine miles off the southwestern coast of Denmark, and the 72-turbine Nysted project, which is located about six miles offshore in the southeastern part of the country.

Because the Horns Rev location is similar to Nantucket Sound, the Danish report addresses some of the same species and issues involved in the Cape Wind proposal, which seeks to build 130 turbines on Horseshoe Shoal in the middle of the sound. Overall, the report echoes many findings in the U.S. Army Corps of Engineers draft environmental impact statement on the Cape Wind project, released roughly two years ago and seen as largely favorable to project developers.

"[The Danish report] reinforces a lot of the things we have said all along," said Cape Wind vice president for project development Craig Olmstead, who attended the conference in Denmark last week. "You have really got to dig deep to find anything negative to wind farms in this whole thing."

Endorsed by an independent panel of international marine scientists, the report used data compiled over the course of eight years from a variety of sources, including radar, infrared video, scuba divers and underwater photos. The studies cost about $15 million, and were funded by a surcharge paid by Danish electricity consumers.

Among other things the report found:

* Strong evidence that offshore turbines are unlikely to have a significant impact on bird populations. According to radar data, more than half of the birds passing the area completely avoided the wind farm, and those that flew through the project changed altitude to avoid collision with turbine blades. Models estimated that roughly one in every 5,000 passing common eiders may have collided with a turbine.

* The main environmental effect resulted from the introduction of hard-bottomed structures on a previously sandy seabed. The underwater turbine bases acted like artificial reefs, and increased the total number and diversity of benthic organisms, such as common mussels, starfish and different species of crab.

* Fish populations neither increased nor decreased in the area, despite scientific speculation that the artificial reefs would provide additional sources of food and shelter. The report noticed some minor behavioral changes among fish near the buried electric cables, but the changes varied according to different types of species.

* Marine mammals, such as harbor seals and porpoises, left the wind farm vicinity during noisy pile driving activities, but largely returned after construction ceased.

The report also surveyed public opinion both before and after construction, and found that people were generally positive toward the two projects. Danish opinion appeared to parallel the Nantucket Sound debate, in that public sentiment was more favorable nationally than locally, and that opposition in nearby communities was based mostly on visual impacts. Interviews with local residents found that even though most people accepted that environmental impacts were largely neutral, they still wanted future projects to be placed farther offshore and out of sight.

Cape Wind opponents this week did not challenge the findings of the Danish studies, but instead highlighted statements in the report that spoke to the need for appropriate siting of offshore projects. Opponents also focused on differences in the permitting process for offshore projects in Denmark and the United States.

The Danish government identifies appropriates sites for offshore wind farms, as established in the national energy policy, and then solicits competitive bids to determine which project is most in the public interest. The Minerals Management Service is now developing a similar process in the United States, but because of special language written into a piece of legislation last year, Cape Wind is exempt from competitive bidding.

Last month marked the five-year anniversary of the initial Cape Wind permit application, and a final decision on the project is not expected for at least another year. Meanwhile, Danish authorities now plan to expand Horns Rev and Nysted - already the two largest offshore wind farms in the world. Wind power in Denmark currently provides some 20 per cent of the nation's electricity consumption, and the report estimated that number may grow to 50 per cent by 2025, with the majority coming from offshore projects.

Noting that large offshore wind farms are in various stages of planning and development across Europe and elsewhere in the United States, the Danish report last week looked favorably on the future of offshore wind energy.

"With higher oil prices and high [carbon dioxide] allowance prices, we expect that a significant proportion of the renewable energy expansion will be delivered by large, offshore wind farms," the report said. "The framework for expansion of offshore wind farms in an environmentally sustainable manner now seems to be in place."