Minnesota Public Utilities Commission staff recommends stricter wind turbine rules
FARGO -- Minnesota Public Utilities Commission staff members recommend longer setback requirements and noise monitoring of wind turbines in response to growing health concerns.
The recommendations, made in a report released this week, will be considered by the five-member commission when it meets Monday to discuss the issues.
Commissioners, who also will hear public comments, could act on the report or delay their decision, Tricia DeBleekere, an energy facilities planner and one of the report's authors, said Wednesday.
In one option, the staff recommendation calls for doubling the minimum setback of turbines from residences from 500 feet to 1,000 feet or the state noise standard, whichever is greater.
Minnesota's noise standard restricts wind turbines from exceeding 50 decibels at night.
In practice, meeting that standard often means placing wind turbines at distances of 700 to 1,200 feet, the report found.
The report follows a scientific "white paper" review of scientific literature by the Minnesota Department of Health last year exploring possible human health effects.
That report was prompted, in part, by concerns in Clay County generated by several large wind projects.
So-called "wind turbine syndrome" includes complaints such as bothersome noise, low-frequency vibrations and strobe-like "shadow flickers" from chronic exposure to wind turbines.
State health officials, drawing from National Research Council findings, noted that noise from wind turbines "generally is not a major concern for humans beyond a half-mile or so," because of design innovations to reduce noise.
Some groups have advocated setbacks of six-tenths of a mile or even 1.25 miles to prevent possible health effects, which the PUC staff report concluded is supported by "scant" evidence.
"Staff believes that a large component of the recent controversy is due to the propagation of misinformation," the report said.
Controversy involving big wind farms stems from a variety of factors, the staff report found, including noise, changes in the landscape and a sense from neighboring land owners that they lack control regarding the developments.
Minnesota, which ranks fifth in wind energy capacity, has 1,400 turbines capable of generating more than 1,800 megawatts of electricity.
But the Minnesota Office of Environmental Services has logged only three complaints made by residents living near wind farms, two of which were resolved by turbine maintenance, the report said.
The third complaint, involving noise, was found within levels that met Minnesota's noise standard.
Wind developers have opposed longer setbacks, the report notes, contending they are not needed and would increase the cost of wind projects and make less land available for wind farms.
The North Dakota Public Service Commission, which has enforced a 1,400-foot setback requirement for wind turbines, plans to review its standard.