Study confirms migrating birds unaffected by Toronto wind turbineA study by Toronto Hydro and WindShare's has confirmed projections that the wind turbine, at Toronto's Exhibition Place, would have no significant impact on local and migrating bird populations: only two dead birds-out of a migrating population of 40 million-were found during the operation of the wind turbine over the study period.
The Exhibition Place Wind Turbine Bird Monitoring Study was conducted during the spring and fall migration periods of 2003. (A 1996 study done for World Wildlife Fund Canada and the Fatal Light Awareness Program (FLAP) determined that some 40 million birds fly over Toronto during these migration periods.)
The wind turbine study found that local birds appear to have adapted easily to the presence of the turbine and simply avoid it. Bird flocks were observed arriving daily to forage on lawns. They landed in parking lots soon after dawn and consistently took a flight path that clearly avoided coming close to the turbine, flying either east or west until they were north of the turbine before landing.
A total of 22 species (starlings, bobolinks, chimney swifts, red-winged blackbirds and others) were observed flying near the turbine blades when in operation and at the height of the blades. Canada geese were close to the turbine on at least half the visits in the autumn and as many as 31 were seen foraging on the lawns below the turbine blades. The mortality monitoring, although not spanning the entire year, covered the times during 2003 when mortality was most likely to occur, i.e. the spring and fall bird migration.
The study described the level of mortality experienced at the wind turbine in 2003 as "absolutely insignificant" when compared with the thousands of birds killed annually in Toronto by striking tall buildings. The mortality experienced, said the report, is closer to that of an individual house where birds hit windows at a rate of between one and ten per year.
"We're very excited to confirm our predictions-that the wind turbine would have minimum impact on local and migrating birds," said Joyce McLean, director of environmental affairs for Toronto Hydro Energy Services. "Having the turbine become such an unobtrusive part of the bird environment only further confirms that we installed the turbine for all of the right reasons."
Toronto Hydro and WindShare built the utility-scale wind turbine at a capital cost of $1.3 million to supply a source of green energy for the community and help improve local air quality. A portion of the project funding ($330,000) was provided through the Technology Early Action Measures (TEAM) component of the federal government's Climate Change Action Fund.
The installation was a North American first, with the turbine supplied by Lagerwey Windturbine International BV, a Netherlands-based manufacturer. The Lagerwey wind turbine, a three-bladed 750 kW gearless generator, will produce approximately 1,400 megawatt hours of power per year, equivalent to the electricity needed for about 250 homes.
It will generate sound levels of approximately 43 decibels at a distance of 250 metres. This compares favourably with typical background noise levels in both quiet suburban residential neighborhoods (ranging from 48 to 52 decibels) and urban residential environments, where background sound levels are slightly higher (between 58 and 62 decibels).
The turbine's three blades, each 24 metres long, were manufactured by Bolwell Corporation, in Huron Park, Ontario (north of London). They are attached to a rotor mounted on a 65-metre high tower and rotate approximately 27 times a minute. From the ground to the tip of the highest blade, the turbine stands 91 metres tall (about 30 stories).
More information is available from Mark Burton at Toronto Hydro, 416/542-3100, ext 30131.