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Aussie wind farms moving forward with 2km setbacks

Human impacts, News, Wind turbines 1 Comment »

Despite much gnashing of teeth among wind developers and some wind advocates, it appears that the Australian wind industry is adjusting to larger setback requirements.  In the past two months, two large wind farms have cleared key approval hurdles in New South Wales, with both incorporating the 2km setback requirement from non-participating homes that is included in draft NSW wind planning guidelines.

The 33-turbine Bodangora Wind Project received approval from the NSW Planning Assessment Commission in late August, which noted that while “noise emissions from the turbines will be audible from some surrounding dwellings,” sound models suggest that sound at non-participating neighbors will be 30dBA or less (and 52dBC or less), noting that “the 2km buffer provided in this instance is highly precautionary.”

CollectorMeanwhile, the 63-turbine Collector Wind Farm has been received a recommendation for approval by the NSW Department of Planning this week, and now awaits final approval from the Planning Assessment Commission.  Despite the recommendation, Tony Hodgson of Friends of Collector said strong opposition remained in the community, which would be enthusiastically voiced at a community meeting with the PAC at the end of October. “We spent a lot of time and a lot of energy putting in our submission, and nobody from the department ever talked to us,” Mr Hodgson said. “We feel very, very hard done by. We think it’s an outrage, and the whole thing’s been a complete waste of our time.”  The Collector project includes one home just inside the 2km buffer, and a couple more just outside it, as seen on the most recent site map (above; yellow line is 2km; red turbine sites have been removed). The project’s Sound Assessment found that the three closest non-participating homes would remain just under the 35dBA noise limit (10-minute average), as well being well below the 60dBC limit.

The NSW Draft Planning Guidelines, which were released in December 2011 and have yet to be finalized, included a requirement that projects receive permission from all homeowners within 2km.  NSW’s southern neighbor Victoria has been operating under a 2km setback requirement for two years now; over 20 wind projects are in the planning stages, with one in the midst of the approval process.  NSW’s other neighbors, South Australia and Queensland, are also charting cautionary paths, though without absolute 2km limits on the table so far (both have 35dBA noise limits, which generally requires setbacks of 1.5km or more).  As in Australia, the US state of Oregon appears to have a robust wind development environment, despite the widespread use of a 36dBA noise limit, which similarly pushes turbines significantly further away from neighboring homes than is typical in much of the US and Canada.

Sandia workshop highlights new understanding of turbulence in wind farms

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A long, detailed article in Windpower Engineering provides a fascinating look at current efforts to understand the complex wind flows in and around wind farms.  Recent research at NREL, Sandia National Laboratory, and Texas Tech is highlighted in the article, which also includes several compelling graphic representations of the patterns of turbine wakes inside wind farms.  For the first time, researchers are now able to measure wind speed and direction in three dimensions in working wind farms, using multiple dopplar radar units; this data has led to new and far more detailed computer models that can be used to investigate how small changes in turbine operations may reduce stresses on downwind turbines.

Read the whole thing at the link above; here are a few teasers:

“It’s almost as if we added a dye into the wind that changes color with speed,” says Moriarty, commenting on the video he presented. “The images show high winds in red or hot colors, and slower winds speeds in blue, and how well downstream turbines are working.

What has been known for a while, he says, is that under certain atmospheric conditions, turbines are getting beat up by what’s called a mildly stable atmosphere. “Even though this has been known for a while, we don’t know exactly what is happening in the flow that influences damage events” says Moriarty.

Although tuning a wind plant is difficult, Moriarty’s simulations suggest adjustments. “We have run several simulations, for example, that de-rate (reduce the power) the first row to let more energy through. That works under some conditions. And then there’s wake steering, moving a wake. Changing the yaw on one or more turbines allows controlling where the wake flows, ideally away from downstream turbines. Depending on yaw angle, results show a 4.5% increase in energy capture.”

UPDATE, 10/17/13: Here’s more on turbulence research, this time in India, where the Tamil Nadu province has some insane turbine densities (check out the image at the link; note the 2km bar at the bottom right).

First ruling in new sonar challenges fails to limit huge take numbers

Effects of Noise on Wildlife, News, Sonar No Comments »

The first ruling is in from the latest round of legal challenges to Naval training permits, and it’s a split decision.  You’ll need to click through to read the full post to get all the details, but here’s a preview of the conclusion you’ll find at the end:

It appears that the places that the court found NMFS falling short are in the details of how they prepare and analyze information, while the end results of the Navy activities and NMFS analysis and permits were upheld as valid. The court did not accept the plaintiff’s core concerns about the huge numbers of animals authorized to be affected (as litigated on the questions of protected habitats, mitigation measures, and cumulative impacts), deferring to the NMFS analysis that deemed even these large numbers to be acceptable, largely because most impacts are minor and temporary. The rulings that went against NMFS each appear to require simply more data analysis, which will then be fed into the same decision-making process that has been upheld as valid. 

In 2012, Earthjustice, NRDC, and others challenged both the 2010 Northwest Training Range Complex permits authorizing five years of mid-frequency active sonar and explosions at sea, and permits authorizing global deployment of low-frequency active sonar through August 2017. While earlier challenges targeted the Navy’s environmental analysisor originally, the lack thereof—and ran aground when the Supreme Court ruled the Navy has broad discretion to weigh environmental safety against national security interests, this new round of lawsuits is directed at the National Marine Fisheries Service’s regulations and permits for the activities. 

In both cases, the primary focus of the challenges, at least as described in press releases, was insufficient protection of biologically important areas.  For several years, NRDC and others have stressed that Navy training ranges, which stretch along nearly the entire east and west coasts of the US, contain enough area for diverse training while setting aside some seasonal or year-round exclusion zones where training is avoided due to concentrations of marine animals.  Navy estimates of the numbers of animals likely to hear sonar or explosions, leading to either behavioral changes or injury, are alarmingly high, and the plaintiffs suggest that these numbers could be reduced significantly by setting some areas off limits, at least at key times. Unlike in previous challenges directed at the Navy itself, the plaintiffs did not seek any sort of injunction to halt the training exercises; rather, they asked that the court require the NMFS to revisit and revise their previous rules or authorizations in light of any deficiencies the court determined to be present.

As the NWTRC case moved into the argument phase, several specific challenges to NMFS procedures, analysis, and conclusions were raised and addressed. In a ruling issued by US Magistrate Judge Nandor Vadas in late September, the plaintiffs came away with at least a temporary win on several points, while the NMFS prevailed on several other fronts, including on the fundamental arguments about habitat protection and long-term impacts.  As in previous rounds of this legal battle, it appears that the end result will be Navy training continuing pretty much as it was before any of the legal challenges began—though with detailed analysis of potential impacts continuing to be pushed into new realms by the legal challenges.

The court ruled that the NMFS had improperly failed to include some relevant studies from 2010 and 2011 when issuing a 2012 Letter of Authorization and Incidental Take Statement, two years after the initial Five-Year Regulations were issued, and so did not rely on the “best available evidence” and likely underestimated the number of animals affected by Navy activity in its 2012 permitting documents.  In addition, the court ruled that the NMFS should analyze impacts not just over the five years of each planning cycle, but for a longer (unspecified) time period, because Navy training is considered to be a permanent, long-term activity.  Over the next month, NMFS will file a brief describing what they see as an appropriate scope and duration of any order to change their previous documents, and the plaintiffs will file a reply; presumably, the Court will rule shortly thereafter on specific remedies.

However, the NMFS prevailed on several substantial issues, including the primary one and two important related challenges.  On the central question of setting aside exclusion zones to better protect essential habitats, the court ruled that the NMFS had given such exclusions due consideration, and lawfully concluded that such exclusions would not be likely to reduce take numbers significantly.  Likewise, the court ruled that NMFS determination of no significant impact did not rely on insufficient mitigation measures (primarily visual observers) in making its assessment of likely harm; rather, NMFS determined that even before mitigation measures were implemented, the numbers of animals affected and the degree of impact did not pose long-term risks to local populations.  

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Powerful mapping sonar likely triggered Madagascar mass stranding

Effects of Noise on Wildlife, Ocean, Sonar 1 Comment »

AEI lay summary of:
Southall, B.L., Rowles, T., Gulland, F., Baird, R. W., and Jepson, P.D. 2013. Final report of the Independent Scientific Review Panel investigating potential contributing factors to a 2008 mass stranding of melon-headed whales (Peponocephala electra) in Antsohihy, Madagascar.
Download full report or executive summary.
See IWC website for report and all supporting materials 

Madagascar whalesWEBFor the first time, a mass stranding appears to have been triggered by a relatively high-frequency mapping sonar; most previous strandings (though rare) have been associated with mid-frequency military sonars.  An international, independent scientific review panel (ISRP) of five well-known marine mammal researchers has concluded that a 2008 stranding event on the northwest coast of Madagascar was likely precipitated by an avoidance response to a multi-beam echo-sounder system (MBES) being used to map the seafloor.

Over a hundred melon-headed whales, deep-water foragers who normally live far offshore, became trapped in a shallow estuary one day after the MBES was active 65km off the coast; locals and international marine conservation organizations collaborated for three weeks to save floundering whales, with at least 75 confirmed dead.  The ISRP investigated all known possible causes for such events, and concluded that the most likely trigger was that the whales were moving away from the sonar, and became trapped in the unfamiliar surroundings of the narrow La Loza Bay estuary.  There, they found it hard to orient and navigate in the shallow, murky water; lack of food sources, stress/fatigue, and an accumulation of small injuries led to eventual death for most.

Madagascar mapWEBAcoustic modeling suggests that the whales would have been able to hear the MBES signals for at least 30km from the survey vessel, to near the island seen on the map to the right, 25km offshore, at which point they apparently continued moving toward shore until straying into the stranding zone.  Why the animals continued moving inshore after the sonar was no longer audible is unclear.  This is a species that normally lives only in deep waters; once the whales moved past the cliff near the survey area and into shallow shelf waters, they may have been quite confused, and further behavioral anomalies (including ending up in the estuary) may be unrelated to the survey sounds.

UPDATE, 10/10/13: This WaPo article includes some skeptical responses, centering on the uncertainties about other factors (before and/or after the MBES sound exposure) that may have contributed to the stranding, and concerns that the strong language of this report could lead to an over-reaction among regulators.  A spokesman for Exxon-Mobil, which helped fund the study and the initial stranding responses, said, “our contract vessel happened to be there in that time frame, but there are so many uncertainties in the area that we’re not sure it’s us.” Still, the company has changed its practices to avoid use of MBES near sharp cliff faces, since the panel speculated that echoes off the cliff may have confused the whales, sending them further inshore.

The ISRP report concludes that “this clearly appears to be an atypical event,” yet also stresses that the MBES system may pose previously unrecognized risks:

It is important to note that these systems, while regularly used throughout the world in hydrographic surveys, are fundamentally different than most other high-frequency mapping or navigational systems (ed. note: or fish-finding sonars). They have relatively lower source frequencies (12 kHz is within the range of likely best hearing sensitivity for all marine mammals), very high output power, and complex configuration of many overlapping beams comprising a wide swath. Intermittent, repeated sounds of this nature could present a salient and potential aversive stimulus.

Click on through for more details on the stranding, the ISRP report, and maps.

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Ontario towns flock to declare themselves “unwilling hosts” for wind farms

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In the wake of several years of heated wind farm resistance in Ontario, premier Kathleen Wynne said several months ago that the province would aim to site new projects in “willing communities.”  In response, 71 southern Ontario communities have formally passed resolutions declaring their towns “unwilling” (red on map; interactive version here) and another 33 have expressed some measure of concern about local siting (yellow); together, this represents a bit over half of the 197 municipalities in the southern part of Ontario where wind development has been concentrated.   A coalition of these towns formed at an August meeting of the Association of Municipalities Ontario. It remains to be seen whether provincial officials will alter siting decision based on these declarations; provisions of an altered wind strategy appear to focus on “consultations” with localities (rather than requiring local approval of projects) and incentives to encourage local support for wind development.

UPDATE, 12/2/13: The Dufferin County Council has voted to declare the county an unwilling host, become the first county to do so; several town within the county are among the over 90 Ontario towns that have made similar declarations.

Unwilling 500

In a statement issued this week, the coalition of “unwilling” towns said: “Municipalities are seeing the impact of existing turbines on their communities or their neighbours and do not want the same things to happen in their municipality.  The government’s proposals for community benefit programs and community sponsorship do not address the core problems being created when wind turbines are located too close to people.”  Added Wainfleet mayor April Jeffs, “Municipalities are looking for solutions to the real problems, not public relations gimmicks.” 

“The government has indicated that an announcement regarding the guidelines for new large-scale FIT projects is planned for the end of October or in early November,” said Kevin Marriott, mayor of Enniskillen. “Municipalities are looking for real planning authority for wind turbines to be returned to local governments.  Municipalities are better placed than Queen’s Park civil servants to identify local issues that need to be addressed in reviewing wind turbine projects. They also have processes in place to review and approve other complex or controversial building projects within their jurisdiction.”

Earlier, Marriott had noted that while the Premier has spoken about wanting to locate projects in willing host communities, no concrete plans have been proposed to give municipalities substantial input in the siting process, and wind turbine projects have continued to get provincial approval without consideration of municipal concerns. 

UPDATE, 10/10/13: This week, a wind project received provincial approval in Kincardine, one of the towns that has declared itself an unwilling host.  One local council member noted with dismay that the province had embarked on an expensive change of siting for two gas-fired electric plants because the initial communities had not welcomed them, while similar concerns about wind farms are ignored.

Indeed, Wynne made her commitment to continued wind development clear even as she attempted to outline a more responsive relationship with communities, stressing that the province needs to find a way to ensure green energy projects are “going to willing communities.” In a draft of the new FIT structure released in September, there was no mention of communities being able to opt-out, though there are provisions for “local consultations.”  

Her Energy Minister, Bob Chiarelli, has been overseeing the revamping of the FIT, including a new requirement that companies consult with local authorities before going to the province for approval.  “They will have a much stronger voice in all of the significant energy projects,” said Chiarelli “Communities spoke, mayors spoke, and we listened.”  Since localities do not seem likely to get veto power, the formal “unwilling hosts” designations appear to be more of a public statement than marking the establishment of wind-free zones.  The revamped FIT program will include incentives including new funding for municipalities who want to do energy planning; Chiarelli said, “We believe that process will result in a much higher level of buy-in and participation by municipalities.”

Well, maybe not, if the summer and fall rush to declare themselves “unwilling hosts” is any indication; it appears that the Ontario wind wars will be continuing.