The wind power industry and clean-energy advocates reacted strongly to a judge's recommendation that the Minnesota Public Utilities Commission reject the permit application for the Freeborn Wind Resource Project, which is planned to straddle the state's border with Iowa.
Comprising 124 wind turbines and slated to cost $300 million, the 200-MW wind farm is being developed by Invenergy LLC under an agreement to sell the project to Xcel Energy Inc. for construction and operation. Freeborn is one of four wind projects with a combined capacity of 750 MW that Xcel in late 2016 agreed to acquire after issuing a request for proposals for 1,500 MW of wind power to serve customers of its Northern States Power Co. - Minnesota and Northern States Power Co. - Wisconsin utilities.
In a May 14 finding, Administrative Law Judge LauraSue Schlatter said the PUC should reject the permit application because of noise concerns. "Freeborn Wind has failed to demonstrate that the proposed project will meet the requirements of ... the applicable Minnesota noise standards," Schlatter concluded.
But that conclusion is based on a novel interpretation of the Minnesota standards, according to Invenergy, other wind energy companies such as Apex Clean Energy and industry groups including the American Wind Energy Association, or AWEA.
"These findings interpret the ... noise standard as regulating 'total noise'" within the project's footprint "such that noise from all sources cannot exceed" a specified level, AWEA said in comments submitted to the PUC.
Wind turbine manufacturer Vestas-American Wind Technology, Inc. in its comments said more typical interpretations refer only to noise produced by the source itself, not including background noise. "Minnesota wind farms have long been found to be in compliance with Minnesota noise standards when noise levels generated by the wind farm source," i.e. the turbines themselves, have registered at or below the regulatory standard, Vestas said. Schlatter's interpretation "departs from established precedent, disregards credible scientific evidence presented under oath and tested by cross-examination, and presents the commission with an unworkable noise testing scheme," the company added.
Softer than AC
"If the [PUC] adopted a 'total noise' standard, such an interpretation would effectively ban future wind development in Minnesota, and potentially provide anti-wind activists a tool to attempt to adversely affect the operation of existing projects," AWEA said.
One opponent of the project, the Association of Freeborn County Landowners, called for "respectful and preventative wind siting" by the commission in considering projects like Freeborn.
Wind turbines have faced objections based on the noise they make since they began being widely deployed in the 1970s. But little scientific evidence exists to show that the noise is detrimental to human health or harmful to wildlife living nearby, and wind power supporters dismiss the idea that the turbines produce annoyingly high sound levels. For instance, information from turbine manufacturer GE indicates that noise levels 300 meters away from a turbine (the minimum setback level for nearly all wind farms in the U.S.) typically reach around 43 decibels — softer than most air conditioners and only slightly louder than the average refrigerator.
Adopting Schlatter's interpretation, Apex Clean Energy said, "would create an incredible amount of regulatory uncertainty, not just in the wind energy sector, but across a variety of segments of the economy, including agricultural, industrial, and transportation."
Schlatter's recommendation is under review by PUC staff, which will prepare a briefing paper for the commissioners. A decision on the permit is expected in the third quarter of 2018. (Minn. docket WS-17-410)