Bat conservation gets a charge from renewable energy
The Service partners with EDF Renewables and the New York State Department of Environmental Conservation to protect bats from the hazards of wind turbines.
Over the last several years, the U.S. Fish and Wildlife Service has received more permit requests for renewable energy projects than ever before.
According to the American Wind Energy Association, in 2019 alone, electricity from wind turbines was estimated to offset the carbon emissions from 42 million cars. But with blades more than 50 yards long whooshing through the sky, there are bound to be complications for winged wildlife. That’s where the Service comes in.
The agency has permitted four wind energy projects across the Northeast for their efforts to minimize and offset effects to threatened and endangered bat species. A number of other partnerships are in development. In New York, the Service is working with EDF Renewables, a North American renewable energy company, and the New York State Department of Environmental Conservation to minimize and offset effects to endangered Indiana bats and threatened northern long-eared bats at the Copenhagen Wind Farm in Lewis and Jefferson counties.
“Impacts to bats present a challenging situation that we are taking leadership on,” said Mike Azeka, senior director of environmental strategy with EDF Renewables. “We’ve invested millions of dollars in testing, to help optimize bat deterrence, and activity monitoring to better inform wind turbine solutions for migratory and hibernating bats.”
Balancing wildlife needs with renewable energy
Federal law prohibits energy companies — or anyone for that matter — from harming threatened or endangered wildlife. When that harm is the unintended consequence of an otherwise legal activity, such as when endangered bats collide with rotating wind turbine blades, the company can develop a plan and seek a permit from the Service that demonstrates their commitments to minimize and offset that unintended harm.
“Our partners recognize that these projects have real effects on wildlife,” said Kevin Connally, a fish and wildlife biologist with the Service. “Habitat conservation plans are all about striking that balance so we can accomplish multiple goals.”
Habitat conservation plans are designed to address the specific effects of each project and offset unavoidable impacts to threatened and endangered species. EDF Renewables decided on two ways to approach this issue at the Copenhagen Wind Farm: adjusting turbine speeds to be less hazardous to bats and installing cave gates to offset other harmful impacts.
Minimization and Mitigation
From July to September, Indiana bats and northern long-eared bats migrate from summer habitat to winter habitat and are at risk of colliding with operating wind turbines. This poses a challenge with turbine blades moving and generating energy: maximizing energy output while simultaneously minimizing unintentional injury or death to the species.
Bats are most active when wind speeds are low. Studies have indicated that immobilizing turbine blades when the bats are at peak activity is an effective minimization measure. Modifying turbine operation when bats are at greatest risk reduces impacts to the species, while still allowing turbine blades to generate electricity at higher wind speeds when bats are less active. This change in operations reduces collisions to the threatened and endangered bats and has been adopted by many wind projects permitted by the Service in the Northeast.
However, those adjustments do not eradicate all risk to these species. To offset any harm that might still occur, EDF Renewables looked off-site for mitigation opportunities.
About 150 miles from the project site are hibernacula, or spaces used by bat colonies for hibernation. Human disturbance during bat hibernation can have very dire consequences on the population, causing bats to wake up and burn through stored fat and die of starvation.
Species decline due to human disturbance is nothing new. In the case of Indiana bats, intentional human disturbance in caves and mines where the bats wintered caused drastic declines in the species populations in the 1960s.
Preventing disruption within hibernacula is even more crucial today due to white-nose syndrome, a fungal disease that grows on the noses of hibernating bats. The disease is thought to cause infected bats to arouse from hibernation more often than normal, leading to depleted energy stores and, often, death. This can compromise the bats’ ability to survive hibernation.
“It’s always been a bad idea to disturb hibernating bats, we’ve known that for decades,” said Carl Herzog, wildlife biologist for NYSDEC. “But it’s especially true in the white-nose era. The disturbance resulting from people going into the hibernation site makes the harm caused by the disease worse. The bats benefit from keeping people out of hibernation sites.”
Alongside the DEC and the Service, EDF Renewables built gates at the entrances to an abandoned mine used by bats as a hibernation site. While the gates don’t keep out the bats or the causative agent of white-nose syndrome, they prevent people from entering the mine and causing more disruption during hibernation. This gives the bats a greater chance of surviving during the winter.
“The primary idea behind mitigation is that we want to fully offset the impacts of harm on the population,” said Western EcoSystems Technology, Inc. biologist and consultant to EDF Renewables Quintana Hayden. “If we’re going to injure a bat under the permit, we want to save a bat that would otherwise be at risk for some kind of impact.”
Producing mitigation efforts not limited to the geography of the wind farm gives freedom to project coordinators to have greater beneficial effects on the species.
“The biggest need for the species might have nothing to do with what’s going on at the site,” said Service biologist Robyn Niver. “It’s a real benefit to have that flexibility.”
Other energy projects permitted by the Service in the Northeast — Beech Ridge Wind Energy and Criterion Wind — gated hibernacula in West Virginia as part of their mitigation as well. In Pennsylvania, companies have the option of contributing to the state’s Indiana Bat Conservation Fund, which has purchased and protected thousands of acres of bat habitat. For example, North Allegheny Wind, of Duke Energy Renewables, contributed over $169,000 to the fund.
The future of renewable energy and wildlife
As interest in renewable energy continues to rise, Niver predicts that the next big renewable technology will bring unforeseen challenges.
“There’s going to be a ‘new’ wind at some point,” Niver said. “A different industry, a different project type, and we’re going to have to figure out what to do for a species. That’s always an interesting challenge when you have a newly listed species that you’ve never had to think about before.”
These projects take an enormous amount of time and dedication, but those involved think the time is well worth it.
“Wind energy is an important part of our future,” said Herzog. “It’s worth the time and trouble to do it, and to do it right.”
