As interest in wind power grows, St. Louis Park expects homeowners to want their own turbines.
If you build an apartment complex in St. Louis Park, the city code says it must have screens in the windows. If you add a dog kennel, it has to be fenced.
But what if you want to put a wind turbine on the roof of a house, or on a tower in a parking lot?
It's an issue no one thought about until recently. Though no one has yet asked the city for permission to erect a small turbine on a house rooftop, St. Louis Park officials expect it will happen and they want to be ready. So they're joining Minneapolis, Maple Grove, Woodbury and other cities that have updated their city codes to manage new "green" technologies.
"Some cities wait until they get approached the first time. Some are doing it in anticipation," said Brian Ross, co-owner of CR Planning of Minneapolis, which prepared a background report on the issue for St. Louis Park.
"As wind energy has become more and more prevalent, and more areas of the state are economically suited to it as the technology gets better, we're seeing places that did not expect to see wind development get calls about it."
Ross' report shows the Twin Cities area in a relative dead zone for wind energy, especially compared with the gusty southwest corner of the state, where utility-sized wind farms have sprouted. But advances in technology and a strong interest in environmentally friendly energy are expected to spur building requests in area cities.
With no space for giant turbines like those seen at St. Olaf and Carleton colleges in Northfield, officials in the Twin Cities are concentrating on regulating small turbines or even micro turbines that rarely generate more than 100 kilowatts and may generate less than a kilowatt.
St. Louis Park expects to have an ordinance drafted by the end of the year, said Kevin Locke, community development director.
"Part of the community's vision is to be good environmental stewards, and energy is a component of that," Locke said. "We could imagine there might be some interest in doing some wind generation of energy. We looked at our zoning ordinances and realized they didn't really address that."
Fitting the local terrain
Possible issues with wind turbines include height, noise, safety and appearance.
"Residential areas are the core of our community, so we're very careful in thinking about what people can do and not do," Locke said. "We're kind of sorting that out right now."
Ross' report points out that rules that are too restrictive can limit turbine effectiveness. Setting a 120-foot limit for turbine towers will allow most small wind turbines to maximize wind power, Ross wrote. But that's higher than many cities consider safe.
In Bloomington, towers for wind generators are covered by the same ordinance that governs antennas, limiting height to 100 feet in industrial areas and 30 feet in residential neighborhoods. St. Louis Park officials are thinking about a maximum tower height of 70 feet in residential areas and 110 to 199 feet in non-residential and commercial districts.
Safety and noise concerns will be considered in drafting ordinances.
"Anytime you have something that's mechanical and moving, you have potential for noise," Ross said. "My sense is that wind generators are pretty quiet, but we want to anticipate what we are going to allow if we have a noisy one."
One-acre minimum lot size
A draft ordinance likely will include a requirement that wind generators be installed only on lots at least an acre in size. Standards also likely will include specifications for setbacks, maintenance, lighting, design and productivity.
Ross said wind generators tend to be quieter and safer than they once were. Some new turbines have automatic braking systems that turn them off if winds get too high. Ross said concern over "ice throw" -- ice chunks supposedly hurled by spinning turbines in wintry weather -- are "a non-issue."
He recently worked with Stearns County to update ordinances because officials think there may be interest in building large wind farms there. That's a sign of how much more efficient wind generators have become and why cities are acting to update their ordinances, Ross said.
"Interest has grown dramatically in places where you did not expect to see it," he said. "Now homeowners are saying, 'Gee, I want a piece of this.' "
Mary Jane Smetanka • 612-673-7380