Companies trying to get ahead in the wind power race can write brilliant business plans and hunt down the best technology but they haven’t gotten anywhere until they’ve learned about bat lungs.
Bats are the newest environmental factor that wind energy producers need to consider when they plan and propose a new project. They have taken over from birds as the animal most threatened by turbines.
But wind power companies, like they did a decade ago with birds, are adjusting by reshaping their project proposals around a changing body of environmental research. It’s costly to stay ahead of environmental assessment demands, they say, but disruptions to wind power projects elsewhere in Canada show how expensive it can be to ignore new research.
Bats are mammals, and that means their lungs are less rigid than those of birds.
They don’t need to be hit by the blades of a wind turbine to die. Simply flying near a turbine can make bats’ lungs collapse as the sudden drop in air pressure creates internal hemorrhaging, and their bodies are sometimes found with no external damage but full of burst blood vessels.
This “barotrauma” was present in 90 per cent of dead bats collected near wind turbines and autopsied by a University of Calgary team led by researcher Erin Baerwald, according to a 2008 study. Only about half the bats were found to have been killed by contact with the turbines.
The news created waves in the wind industry, and Nova Scotia was no exception.
“They were kind of ignored early on, and now I believe bats are more of an issue than birds,” said Andy MacCallum, development manager for Fairmont Wind Farm, a project planned near Antigonish by global company Wind Prospect Inc.
MacCallum and his colleagues stay on top of the location of bat caves, as well as bird migration patterns and other ecological facts of Nova Scotia, with the help of consulting firms that have built up local environmental expertise specific to the needs of the wind power industry.
Planning around nature happens from the earliest stages, said MacCallum.
A company will stay away from a bat cave, and if it discovers new environmental problems in the course of its research, it will scrap the planned location or make other changes, he said.
“Early on in the process, we make sure that the sites are away from the environmentally sensitive areas,” said MacCallum.
“Before we even go public, there’s a lot of work behind the scenes.”
None of this is cheap, and it has changed some of the operating principles of wind power companies. Environmental assessment studies, which the province requires for each proposed wind farm, often cost upward of $100,000, with followup studies costing $10,000 to $20,000 every year for several years, said MacCallum.
The numbers stay roughly the same no matter how much revenue a farm is expected to bring in, making bigger wind farms more cost-effective.
Some companies manage to get around the entire cost of environmental assessment by installing a turbine that produces less than two megawatts of power. Once a farm hits two megawatts of production, it is legally required to do an assessment, which has made 1.9-megawatt turbines more popular, MacCallum said.
Then there’s the need to tweak technology – and revenues – mid-production, according to the latest scientific research on animals like bats.
The same University of Calgary team found that programming wind turbines to stop turning during times of low wind dramatically cut down on bat deaths, an idea that the Fairmont farm is looking at.
Sprott Power works regularly with Saint Mary’s University biologist Hugh Broders, who advised the company to put up bat-tracking devices when it first installs its turbines, said chief operating officer Don Bartlett.
He said the company benefits by “just kind of getting ahead of the curve and getting as much data as one can in order to determine if there are any potential issues.”
Failing to take steps like this can lead to problems down the road. Environmental organization Nature Canada is campaigning for a major wind farm near Kingston, Ont., to stop production a couple of weeks a year during top migration season for local birds.
No Nova Scotia wind power companies have faced similar demands, according to Wayne Groszko, renewable energy co-ordinator at the Ecology Action Centre. But if Nova Scotia takes a closer look at the wind industry, it could ask companies to make such major changes, he said.
“Would it be best to shut them off for a few times each year? Would it be best to reduce their cutting speed? I don’t think that kind of research has been done yet in Nova Scotia.”
People tend to ask wind power producers to live up to their reputation for green energy, Groszko said.
“Wind turbines are extremely visible to a lot of people.”
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