Gar Lipow over at Grist has a quite detailed post today that looks at the promise of various proposed “Flying Energy Generators:”  tethered kite- or plane-like flying platforms for wind generation, able to tap into orders-of-magnitude more available wind energy than ground-based towers.  The piece addresses questions and concerns that are sure to arise about such a “pie in the sky” idea, and concludes that several designs that have completed a proof of concept phase are ready and enticing targets for truly modest government or venture funding to quarter and full scale commercial prototypes.  Links to companies working on several of the most promising approaches will really whet your appetite for more. Well worth a look!
More Than Pie in the Sky: Flying Energy Generators, Maybe the Next Big Thing

Two pieces of wind farm noise news out of Australia this week, both of which address health concerns.  Residents near the Waubra wind farm in Victoria, which began operating in February 2009, have been affected by the noise, some to the point where they’ve moved away.  A recent report by the federal government health office came to the familiar conclusion that there is no “direct, causal” link between wind farm noise and health effect, but as is common in these reports, little attention was directed toward looking at indirect impacts of sleep disruption or annoyance, and the authors of the report did not meet with any of the people who have experienced changes in their health after wind farms became operational.

In response, a Melbourne Senator has called for further inquiry. Senator Steve Fielding noted that ”I think it’s only fair that if a cluster of symptoms arise in a local population at approximately the same time we owe it to the people to take a closer look,” said Senator Steve Fielding. ”We all want to live in a clean environment, but we need to make sure it’s not at the cost of the local population who have to live near wind farms. It may be the case that we need to set out guidelines as to how close wind farms can be built to someone’s home, but I wouldn’t want to pre-empt any Senate inquiry.”

Meanwhile, one of the residents who had to move from his house, Noel Dean, commissioned a sound assessment by an independent acoustical engineer, Robert Thorne.  Thorne has submitted his findings to several regulatory agencies in recent months; there has been no significant challenge to his findings from wind farm developers, though he has responded to some specific critiques in his final report, which was just released.  Thorne’s report includes detailed sound measurements taken at the Dean residence; the results largely affirm that infrasound is well below audible levels, while also showing that the turbine sound spectrum (how loud the turbine is at each frequency) is often weighted toward lower-frequency audible and inaudible infrasound frequencies.  He finds a strong pulsing character to the noise, and notes the many meteorological factors that contribute to variability in actual sound levels that are not fully captured by current sound models. The report also contains a section assessing health effects, with good reference to other studies; his conclusion is that “Adverse health effects such as sleep disturbance, anxiety, stress and headaches are, in my view, a health nuisance.” Thorne takes some of the government reports to task for being incomplete assessments, and themselves not peer-reviewed.  The report concludes with a section assessing vibration, which is present, but well below levels considered problematic.  Addendums include a detailed assessment of noise complaints at several wind farms, including the Te Rere Hau wind farm in Palmerston North, New Zealand, where noise issues have occurred at far greater ranges than are observed elsewhere (surprisingly severe impacts are reported at distances of 2100-3100 meters, or almost two miles).

While it looks like it’s been on the drawing board since at least 2004, today I ran across a news report on what appears to be an increasingly well-defined plan to outfit surface ships with a new Continuous Active Sonar (CAS) system.  In the face of what is perceived as an increasing threat from quiet subs, along with the increasing costs of compliance with environmental regulations that now govern current sonar systems (primarily the mid-frequency active sonar deployed on hundreds of ships, along with gradually increasing use of low-frequency active sonar on two US and a few UK ships), research and development efforts are turning toward the possibility of using a continuous, lower power sonar system to protect Naval vessels.

The sinking of a South Korean vessel, along with the embarrassing appearance of a Chinese sub that surfaced, undetected, within firing range of a US aircraft carrier group in 2006, has highlighted the gaps in detection that are inevitable using a sonar surveillance system that is only activated at times.  While none of the news or technical pages that I found specified the projected source level or frequency range of the new CAS system, one of its benefits was repeatedly claimed to be that it would broadcast at a lower power level, thus reducing impacts on marine species.  It sounds like they would trade the drawbacks of high sound levels for the different but not insignificant effects of adding more continuous background noise to the ocean environment.  One of the rarely-noted factors that may well contribute to the behavioral responses seen in reaction to the the current generation of mid-frequency active sonar is the chaotic, and quite disturbing, nature of the sound source; this is sometimes referred to as the kurtosis of the sound (how many sharp or abrupt elements there are in the sound itself, including sudden rise times rather than more rounded sine-like changes in intensity that are heard in most naturally-produced sounds).  If there is to be a new generation of continuously-broadcasting sonars, let us hope that the sounds themselves are more closely modeled on naturally-occuring sound patterns.

For more on the Continuous Active Sonar system, see:
The recent news report, about research at Alion Science and Technology in Mystic, CT
These two pages from Signal Systems Corporation, also researching the system
A recent Congressional earmark for research
This 2006 news report on a Signal Systems contract that mentions CAS
A September 2009 Navy powerpoint presentation on advanced development plans for undersea systems, which includes a slide on CAS

Ocean Conservation Research has been studying the implications of kurtosis and rise times to ocean noise sources, especially sonar.  For more, see this research page, and especially these two papers and this audio-video demonstration.

Most of the new wind turbine designs you see floating around the tech blogosphere are oriented toward small backyard turbines, in the tens or hundreds of kW range.  So it was kind of a thrill to see this new design for a 10MW offshore turbine, partly inspired by a spinning sycamore seed:

Aerogenerator X concept

After an 18-month feasibility study funded by a consortium of energy companies and the UK government, new funding and agreements are moving the project forward, with the goal of building a full-scale test version of the design by 2013 or 2014.  The current version is over 900 feet across, but half the height of vertical turbines (which would have the benefit of creating a markedly lower visual profile from shore, and even being “over the horizon” in many more near-shore locations).  The power-generating equipment sits at the bottom, rather than the top as in a tower, greatly reducing both the cost and complications of servicing. The horizontal design reduces pressure on the blades (which rotate just 3 times per minute), thus breaking through a stress barrier that will likely limit traditional turbine designs from moving much past the currently-envisioned 5MW size.  The drawback is that the lower profile will not access higher wind speeds at greater heights.

Here at AEI, we have great hopes for offshore wind, which moves the noise far from people’s homes, while tapping into a very consistent wind resource.  It’s not clear from the current news reports whether this design can be adapted to our ideal long-term scenario of floating turbine platforms (which allow deployment farther offshore in higher winds, and also greatly reduce the amount of loud construction noise, which is the primary impact off offshore wind on ocean acoustic ecology.) New conceptual technologies should always be treated as speculative, but this one does seem to be moving forward at a pretty good clip.  For more info:
Here’s the company press release, which has the most detail
And here are three blog reports on the announcement.

As noted here on AIEnews in May, a single new wind turbine in Falmouth, Massachusetts triggered noise problems for many nearby residents (12 formal complaints were filed, an unusually high number for any community, and residents of up to 45 of the 120 homes within a mile raised concerns in informal local meetings).  The town appears to have responded quickly: this news report from mid-June notes that the turbines had been shut off 39 times in the preceding month, when winds topped 22mph and noise would have been at its worst.  Both the town and a group of neighbors have hired lawyers and sound consultants to help them work through the situation; everyone spent a month discussing the nature of the noise issues as a study was designed to assess the conditions in which noise is the worst.  This recent article from the Falmouth Enterprise (sorry, no direct link found) summarizes the recent noise measurements made by both the town and residents’ sound consultants, and the first survey that recently took place.  Everyone seems to agree that the sound was much worse in its first three months of operation (March-May), when winds were higher, so it’s not altogether clear whether this survey, taken at a time when the air was quite hot and still, will suffice to answer the longer-term questions.

Falmouth is the second small New England town to run into unexpected noise problems after installing wind turbines in an effort to reduce electric bills and contribute to a sustainable energy future in their localities. Residents of Vinalhaven, Maine are also trying to find the balance between wind energy and local quality of life; AEInews has tracked their efforts since last December. It appears that Falmouth is being a bit more pro-active, as evidenced by the quick decision to shut down turbines in high winds.  By contrast, the sound study project proceeded a bit more slowly in Falmouth, which may also be a good thing; in Vinalhaven, there was some confusion and uncertainty as a noise survey commenced suddenly this winter, without much pre-consultation with neighbors of the turbines on the design of the study or the sorts of qualitative descriptors used on the surveys (which some neighbors found did not encompass the sounds they experienced).

This is new territory for every town that grapples with it; both Falmouth and Vinalhaven are at the forefront of constructively dealing with noise issues (especially in contrast most wind projects, where the turbines are owned by large and comparatively impersonal energy companies).  As more towns and energy co-ops consider erecting small wind projects, the lessons learned in Falmouth and Vinalhaven will serve to make the process of dealing with noise issues a bit easier elsewhere.

As many of you know, over the past two years, the Navy has completed its first-ever Environmental Impact Statements for mid-frequency active sonar, in concert with applying for permits to allow them to do sonar training missions in Naval training ranges off most of the coastlines of the US.  This training activity has been ongoing for decades, but after the infamous stranding event at a Bahama range in 2000, and legal pressure applied by NRDC and others, in the mid-2000’s the Navy initiated the process of complying with NEPA provisions that govern activities that may have harmful consequences for wildlife (an internal memo shortly after the Bahamas incident suggested the need to comply with NEPA, but formal compliance activities did not begin until after a 2004 lawsuit).

During 2009 and 2010, the Navy has filed its final EIS’s on most of its ranges, but the environmental compliance treadmill never really ceases, because their authorizations must be renewed every five years: this week, work began on the next round of EIS’s, aiming for 2014 deadlines by which the new ones must be finalized.  The initial scoping phase has begun for activities along the Atlantic Coast and around Hawaii and off Southern California, including some public hearings and fall deadlines for initial comments, which will inform the first Draft EIS’s for each area. The Portland (Maine) Press Herald covers the Atlantic process (and here’s a link to the Navy’s Atlantic Fleet Training and Testing EIS page) and the San Jose Mercury News chimes in on Hawaii and SoCal, which generated separate EIS’s in the initial round, but will be combined this time into a Hawaii-Southern California Training and Testing EIS.

You are invited to participate in the first World Listening Day, which happens on Sunday, July 18, 2010. The purposes of World Listening Day are:

• To celebrate the practice of listening as it relates to the world around us, environmental awareness, and acoustic ecology
• To raise awareness about issues related to the World Soundscape Project, World Listening Project, World Forum for Acoustic Ecology, and individual and group efforts
• To creatively explore phonography to design and implement educational initiatives which explore these concepts and practices

July 18 was chosen as the date for World Listening Day because it is the birthday of the Canadian composer R. Murray Schafer. Schafer is one of the founders of the Acoustic Ecology movement. The World Soundscape Project, which he directed, is an important organization which has inspired a lot of activity in this field, and his book Soundscape: The Tuning of the World helped to define many of the terms and background behind the acoustic ecology movement.

For more information see this info from the World Listening Project, download a press release that includes links to other sponsors and participating organizations, or contact: worldlistening@gmail.com

I’ll be one of three presenters at what promises to be an informative 90-minute webinar taking place on Tuesday July 13.  It’s one of a series of wind energy programs being produced by the New England Wind Energy Education Project, a DOE-funded public information effort.  My piece will add a look at the experiential reports of wind farm neighbors, as well as the few studies we have that help clarify how common noise disturbances are around wind farms (hint: it’s much more than many people think, but also less than some believe); I also take a stab at understanding the variable responses of people hearing the same levels of sound/noise.  Joining me on the panel are Mark Bastasch, who will provide a primer on noise measurement and the sources of wind turbine sounds, and Ken Kalinsky, who will focus largely on the various approaches to regulating wind farm noise.  The three 20-minute presentations will be followed by a discussion and question and answer session that will last for roughly a half hour or so.

The webinar will take place on Tuesday July 13, from 2-3:30pm Eastern Daylight Time.  You must pre-register to receive login information.
For more information on this free webinar, see this PDF information sheet.  You can register from there by email; or, just use this email link and request registration information for Webinar #2.

Indian cities are renowned for their wild and exuberant variety of sounds: honking horns, bellowing loudspeakers, raucous holiday parades, and, much much more.  Now, urban areas are beginning to try to rein in the noise-making, at least at night.  A nationwide decree deems 10am to 6am as a time for quiet, during which restrictions have been imposed on the use of horns, sound-emitting construction equipments and bursting of firecrackers,” the federal environment ministry said.

Indian officials also announced noise-monitoring stations in major cities, including New Delhi, Mumbai and Bangalore, by September.  Eighteen more cities will join the system by 2011, the ministry said. “With the new system in place, a systematic national level monitoring and reporting network in the country will be available, as in case of air and water pollution.”

For more, see this CNN report.

Ontario’s environment ministry has released proposed siting guidelines for offshore wind turbines that set a minimum distance of 5km (3.1 miles) from shore.  The rules, which are now open for public comment, will be subject to public hearings in the fall. Ontario does not have ocean frontage; the rules are meant to govern wind farms planned for the Great Lakes.

The proposed standard would undermine some proposed wind farms, which are aiming to be 2-4km from shore.  It is likely that the proposal would greatly minimize the visual impact of turbines, and would may also reduce sound impacts to an acceptable level.  As noted in this brief essay, sound travels very easily over water, so that typical onshore setbacks could be insufficient for offshore sites.  Some reports from near the Wolfe Island wind farm (at the end of Lake Ontario, near the start of the St. Lawrence Seaway) suggest they are often quite audible from two miles, and occasionally somewhat audible at five to seven miles.  While there is often an assumption that wave sounds will easily drown out distant turbines, it’s likely that people living somewhat inland from the shoreline in otherwise very quiet rural areas would be the most affected by offshore turbine sounds.

One of the more promising green energy technologies is wave power: off every coastline, near urban centers, a steady surge of waves holds the promise of round-the-clock power generation.  As ever, though, there are possible environmental impacts; one of the main ones for wave energy is the possibility of collisions with migrating whales.  Large baleen whales (gray, humpback, fin, blue) don’t use echolocation to forage, so are unlikely to notice offshore installations from a distance.  They are, however, careful listeners, and so Oregon State University researcher Bruce Mate is preparing to test a noise-making system that he hopes will hit the Goldilocks spot for migrating Gray whales: loud and un-natural enough to get there attention, but not so loud that it will cause widespread impacts.

“We do not even expect gray whales to react to the sound unless they are within 500 to 750 meters of the mooring location,” Mate said. “We’re not talking about much sound here.”  Mate said the acoustic device would emit one-eighth of one watt, which they hope will make the whales alter their paths about 500 meters from the noise. The system will be tested this fall, during the migration of single male Gray whales, and be suspended before mother-calf pairs begin their transit of the Oregon coast.

Ocean Power Technologies mockup

Ocean Power Technologies aims to deploy 12 wave power units 2.5 miles off Reedsport, Oregon, by 2012.  While whales may adapt fine to the new structures, the risk of a collision is considered to be something that could set back offshore renewable energy development for years.  The current research could inform future protective measures, should regulators or industry decide that they are necessary.

For more, see this OSU press release, this good overview article in Forbes, and this post on the Smart Planet blog.

The American Society for Acoustic Ecology is pleased to announce ASAE Chicago: Listening for the Future.

This is the first-ever national gathering of the ASAE membership and the general public. Hosted by the Midwest Society for Acoustic Ecology and the World Listening Project, Listening for the Future will take place from July 9-11, 2010. We think it’s going to be a fantastic three days, with plenty of information and inspiration to go around. We hope you will join us at this landmark event.

Additional details will be posted on the Listening for the Future web page. Please bookmark and check back often as we’ll be making frequent updates from here forward. A registration page will be posted early next week, along with locations of all venues, maps, schedules etc.

Event Highlights

Friday (7/9) - Friday (7/9) - ‘Citizen Sound’ symposium featuring a wine and cheese reception, introductions to each of the ASAE chapters, and presentations by leaders in Chicago’s cultural and advocacy scene. Featured guests include Lou Mallozzi, Executive Director of Experimental Sound Studio and architect Graham Balkany of the Gropius in Chicago Coalition. A media lounge, where guests can sample CDs and peruse publications by participants, performers and ASAE members, will be open all night. Following dinner at a local eatery, Read the rest of this entry »

Litchfield NY is considering a relatively flexible, while stringent, local ordinance to govern construction of wind farms.  As proposed by a committee of residents charged by the Town Council, the ordinance would avoid strict setback or decibel limits, and instead require easements to be obtained from all residents within 6500 feet of a turbine (just under a mile and a quarter).

The proposed ordinance now goes to the Council for consideration, where some changes are expected to be made.  Involving all neighbors who may be affected by new wind turbines could be a very effective approach, as both studies and experience shows that when people are involved in the decision to move forward with a wind farm (and compensated financially, or feel shared ownership), they are far less likely to have negative reactions and experiences.  I’m sure that the distance at which easements are required will be a sticking point for all concerned; as proposed, it encompasses a large grey area (from roughly 3500-6500 feet) in which acoustic effects are likely to be minimal, yet possible a small proportion of the time.  If the easements don’t effectively become vetoes, it’s quite likely that being involved in the decision could play a key role in this range.  Closer than a half mile or so, the proposed easements may well be sometimes used as a veto, as at least a few residents are apt to feel that the risk of noise issues is not outweighed by financial benefits in the project.  Still, the easement approach has many benefits over a strict decibel or setback limit, assuring that the developer is engaged with everyone who may be affected by the project.

An article in Der Spiegel reveals that the environmental impact study at a 12-turbine wind farm 30km off the coast of Germany has reported that during construction of the turbines, porpoises avoided an area in a 20-mile radius of the two-square mile construction site.  Harbor porpoises are well known to be more sensitive to sound than many ocean creatures, and may serve as a sort of “canary in the construction zone,” their stark behavioral response standing as an indicator of noise levels that likely interfere with other animals, as well.

Future construction could affect a far larger number of animals than the relatively modest construction that has taken place so far. (click to see larger Der Spiegel image)

This one passed under my radar in January, but has some potentially interesting implications for people working to minimize the negative effects of wind farms on wildlife and humans, in that the developer agreed to shut turbines down at night, at least temporarily.  In December, a Federal court halted construction of the Beech Ridge wind farm in West Virginia, because Indiana Bats, officially listed Endangered Species, live nearby, and the developers had not obtained the necessary Incidental Take Permits that govern activities that may impact such species.  In a settlement announced in January, Beech Ridge Energy, a subsidiary of Invenergy, agreed to forego construction of 24 turbines closest to the bat caves, while receiving approval to operate the 40 turbines that are already constructed, to complete construction of 27 more, and to move forward on planning for an additional 33 units (though the units not yet constructed may not begin operating until the ITP is received).

Most strikingly, the company agreed that all operational turbines will be shut down at night from April to November 15, when the bats are out and about.  During the hibernation season, from mid-November through March, the turbines can operate around the clock.  Future operating conditions, including the need for night-time curtailments, will be subject to the determination of the US Fish and Wildlife Service Incidental Take Permits. Noise is not the issue here, but rather bat mortality near wind turbines, likely caused by rapid changes in air pressure.

It is encouraging to see the viability of operational restrictions being experimented with, and accepted by  both industry and environmental groups as a way forward through a contentious issue.  Indiana Bats are not known to travel in the area of the wind farm, though the proximity of their caves suggests they may; monitoring done by the company was challenged in the lawsuit as insufficient.  Ongoing acoustic surveys will help clarify how common they are, and the USFWS may decide that night time restrictions are unnecessary.  As part of this settlement, the company agreed not to appeal the judge’s decision, and the environmental plaintiffs agreed not to appeal the eventual ITP decision by USFWS.

Happy talk all around after the agreement: Dave Burhman, spokesman for MCRE, said, “We believe our actions have sent a vitally needed message to the wind industry as a whole. Renewable energy projects do not get a pass on existing laws designed to protect endangered species and the natural environment. And although industrial wind turbines will now spin atop some of Greenbrier County’s highest ridges, they will forever be banned on those ridges in closest proximity to endangered Indiana bat caves.”  And Joe Condo, general counsel for the company, agreed that “We are very pleased to have reached an agreement that allows us to move forward with creating clean, renewable energy in Greenbrier County while at the same time meeting the goals of important wildlife conservation efforts.

Sources:
Beckley Register-Herald, 1/27/10
West Virginia Highlands Conservancy, 2/10/10

As noted in a previous post, a recent report by the Chief Medical Officer of Health (CMOH) in Ontario focused on the narrow question of whether there is a “direct causal link between wind turbine noise and adverse health effects” experienced by some wind farm neighbors.  Based on a review of published research, the answer was, “no.”  This week, two of the people who were on the review committee providing feedback on the report as it moved from draft to final form noted that the final version dropped a section that some reviewers had urged be included, which would have more directly addressed the actual experiences of communities near wind farms.

Dr. Hazel Lynn, the Grey Bruce medical officer of health, told the Owen Sound Sun-Times, “The whole section that a couple of us really wanted in there on community health and community disruption went. It’s not in there. I suspect politically she can’t criticize another ministry, so I was a little disappointed.”

“I think it’s a fair comment that there is other material that could have been in the report and wasn’t,” added Dr. Ray Copes, the director of environmental and occupational health at the Ontario Agency for Health Protection and Promotion and another member of the committee that reviewed drafts of the report. Copes said there are “really important and quite legitimate” questions about wind farms that he and Lynn thought should be discussed, but “I guess the CMOH’s report wasn’t the place for it.”

Both Lynn and Copes stressed that they agreed with the report as far as it went, and that direct noise levels and sound qualities of wind farms don’t appear likely to directly cause health problems.  Lynn noted that there is an “association” between wind farms and some health effects, but that these effects also occur elsewhere; still, she said, “Basically, I think they (wind farms) disrupt communities if they’re not properly planned and instituted and when you disrupt people’s communities they get sick.” There is evidence to back that position up, she added, but “that doesn’t come through very clearly” in King’s report. Likewise, Copes stressed that the idea of a unique quality in wind farm noise causing a new set of health problems seems “implausible,” yet he also stressed (as did AEI) that the report highlights the need for more direct measurements of sound levels around wind farms.  Such measurements will add much-needed ground truthing to the sound models currently used in siting decisions, and could provide more concrete data to use in assessing both noise complaints and health concerns.