The newest wind turbines are nearly 500 feet tall and will be needed in Michigan to try to meet the demands of Proposal 3, the 25 percent renewable energy mandate, if voters pass the amendment in November.
That’s because almost the entire state of Michigan is “poor” or “marginal” for wind as a resource at 50 meters above ground (see image), according to the U.S. Department of Energy’s National Renewable Energy Laboratory. The information says Michigan’s best wind opportunities at 50 meters, which would be classified as “excellent” and “outstanding,” are all located offshore.
The National Renewable Energy Laboratory says annual wind speeds of about 6.5 meters per second at 80 meters or higher are “generally considered to have a resource suitable for wind development.”
The 2010 Michigan map of wind strength 80 meters off the ground shows about 25 percent of the state (including the Upper Peninsula) would reach that “suitable for wind development” standard at 6 to 6.5 meters per second. There is also a small area in the northern thumb between Bay City and Port Huron that has wind speeds of 6.5 to 7.5 meters per second.
By comparison, the entire panhandle of the state of Oklahoma has wind speeds measured at 8 to 9 meters per second at 80 meters above the ground.
Proposal 3 would require that the state add as many as 13 times more wind turbines in Michigan than currently operate. Proposal 3 would mandate that 25 percent of Michigan’s energy come from renewable sources. Wind is expected to be the primary supplier of renewable energy if the proposal passes.
Advocates and experts predict 2,300 to 3,790 nearly 500-feet high wind turbines would have to be added to meet the 25-percent mandate. Michigan currently has 292 wind turbines in operation.
The maps show that Michigan’s best wind options are offshore.
The U.S. Energy Information Administration has estimated that although offshore wind can have four times the capacity as onshore wind, it costs almost two-and-a-half times as much to generate that electricity.
“The offshore winds are far better than the on shore wind resources — the problem is that water depths make offshore wind much more expensive and those living on the expensive lake front properties don’t want their views changed or the peace disturbed,” said Thomas Hewson, principal of Energy Ventures Analysis Inc. in Virginia. “Michigan still has relatively poor wind resources making the 25 percent law expensive and not making a lot of sense.”
Michigan Environmental Council Spokesman Hugh McDiarmid said the group thinks there is enough wind in the state.
“We would rank Michigan’s wind potential as more than adequate to meet the 25 percent standard reliably and affordably,” he said.
McDiarmid pointed to a 2003 map done by AWS Truepower that showed that about half the state had wind speeds of 7 to 8 meters per second at 100 meters above the ground. That was a higher estimate than the 2010 map for which Truepower also provided the data for the National Renewable Energy Laboratory.
Lisa Andrews, spokeswoman for AWS Truepower, said there were more “actual wind” measurements in the 2010 map and it was more accurate than the 2003 map.
She said the 2003 map also included offshore wind data, which is much higher than the inland wind. The 2010 map didn’t include offshore wind data. Andrews said wind gets stronger the higher off the ground it is measured.
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