Almost everyone wants to see more renewable power generation, but the compromise between conservationists and power companies can be an uneasy one. Just recently, a prairie dog colony was evicted from a site in East Flagstaff, while turbines at the pending wind power generation site near Williams may kill birds and bats, as well as displace other wildlife. What can be done to reduce impacts of renewable power generation on wildlife?
“Solar energy in itself is not unique in terms of impacts on wildlife – it’s like any other development,” said Steven Gotfried, Renewables Spokesperson for APS. “You need your energy generation system – renewable or otherwise – as close as possible to the location where it’s needed.” Gotfried explains that solar panels also work best with a stable surface on which to mount them. Therefore, there was no option to let the prairie dogs coexist with the new APS solar site at the Doney Park site. After the site has been graded, a surface of cinders or composite will be added to allow vehicular access and to keep the fenced in land around the panels vegetation-free as a fire prevention precaution.
While some believe the prairie dog relocation can be seen as an example of a downside to solar power, it should be noted that APS paid for the relocation, despite the fact that there was no legal requirement for them to do so, says Karin Wadsack. She’s a consultant on renewable energy and environmental policy at NAU’s Landsward Institute, as well as working for EN3 Professionals, LLC a local environmental and civil engineering firm consulting for this latest APS solar project. Wadsack explains that the installation has many positive aspects. APS originally purchased the 10-acre parcel east of town as a location for a new electric power substation, but only needed two acres for that and so decided to add a community solar generation project to the site. It’s a pilot program partly funded by U.S. Department of Energy, designed to help understand the impact on power quality and reliability of the local grid where there’s a significant contribution from solar. As well as the bank of solar panels, the “Doney Park Renewable Energy” project will also see APS “borrowing” rooftop space to install panels at 200 nearby residences. Homeowners won’t own panels, but will sign a 20-year agreement to have them on their roofs.
So why aren’t more panels being located on residential roofs, allowing prairie dogs and other wildlife to remain undisturbed? That’s mostly a result of cost – and other practicalities. According to the latest figures from the National Renewable Energy Laboratory, residential roof top installations typically cost $6.50 per Kw of electricity generated, while utility-scale banks of panels only cost $4.20 per Kw. Not only are utility-scale schemes cheaper, but panels on individual roofs can pose more maintenance challenges – and some roofs are simply not appropriate for solar panels because they are shaded or face the wrong direction. Another factor is dealing with the variations in power flow from panels on customer roofs. How such variations impact the performance of the overall energy delivery system is not currently well understood, hence the need for studies such as the one in Doney Park.
Wind power can also have negative effects on wildlife – turbine blades are known to kill birds and bats. And while there hasn’t been much large-scale wind generation near Flagstaff so far, a new wind farm near Williams would change all that. A subsidiary of NextEra Energy Resources plans to install a wind farm at Perrin Ranch, 10 miles north of Williams just west of State Rte 64. With a generating capacity of 99 MW, it will be one of the largest wind energy project in the state. The plans for 62 wind turbines (each 405 feet high) have elicited complaints – with three of the turbine locations having been adjusted to mitigate effects on the viewshed and increase their distance from residences on the northern boundary. NextEra spokesman Steve Stengel says that their two main concerns are safety and good environmental stewardship and that the company tries to incorporate alternate turbine sites with every project when possible to allow maximum flexibility to accommodate environmental issues.
Mark Ogonowski, Urban Wildlife Planner with Arizona Game & Fish Department, is closely involved with the environmental planning at Perrin Ranch and elsewhere. He says that the principal instrument AZGFD and its regulatory counterpart, the U.S. Fish and Wildlife Service use is the recently developed Avian and Bat Protection Plan (or ABPP). Ogonowki says that it is vital to collect rigorous wildlife data work before construction, to help developers locate turbines wisely. AZGFD has been working collaboratively with Coconino County, NextEra and the consultants hired by the wind company to carry out wildlife monitoring, to ensure that the Perrin Ranch turbines aren’t near landscape features likely to attract wildlife, e.g. riparian habitats, steep cliffs and deep canyons, or corridors for raptor and bat migration. Concerns that California condors might use the area or bats might roost in Cataract Canyon (the only prominent landscape feature) have been addressed by surveys, which have found no evidence of either.
NextEra Energy is providing financial support for wildlife studies at the site – those findings will help Perrin Ranch and other future Arizona wind farms to minimize wildlife impacts. Research from other parts of the country has shown that there are strategies that can reduce turbine-caused bird and bat mortality. Clustering towers together (for example, away from prairie dog colonies) reduces raptor mortalities. Research on avian collisions with communications towers suggests that avoiding continuous night lighting on towers may also help stop bats and migrating birds from being attracted to turbines, while increasing the minimum wind speed at which turbines begin to rotate can significantly lower bat fatalities.
The evidence so far is that careful location choice is the key to minimizing adverse impacts of wind and solar energy development. And with such great potential for renewable energy in our region, the hope is that proper siting along with all other available measures will be used to keep renewable energy generation as green as possible. FBN
Photo: Tish Bogan-Ozmun, President of the Board of Habitat Harmony
Photo taken by Tom Bean