Friday, December 14, 2012

URI scientists report on wind energy potential in southern New England

Great potential offshore. Not so much inland
Wind data makes this scenic vista more and more unlikely
By Will Collette

As Charlestown gears up for more litigation and legal costs over the unpopular Whalerock industrial wind farm project proposed by developer Larry LeBlanc, it’s great timing to see new data showing how practical that project really is.

The short answer: not so much. And that conclusion is consistent with data drawn from several other locations around southern New England, according to new findings released by oceanographers at the University of Rhode Island.

The researchers presented their findings at the fall meeting of the American Geophysical Union in San Francisco. They note that long-term wind speeds have actually dropped off at inland sites while remaining steady and strong offshore.

That’s good news for Deepwater Wind and Cape Wind and their planned offshore wind farms, but bad news for Larry LeBlanc.

The URI scientists found that wind speeds measured over a 35-year period dropped off from an average of 9 knots to 7.7 knots at TF Green Airport and from 8.2 knots to 7 knots at New Bedford Airport.

The researchers theorize that climate change and urbanization may be factors in these long-term data changes. "Southern New England has typically had a long period of frequent winter storms, but with climate change, that pattern of winter weather is shifting to the north, meaning we may be in that pattern less often," said URI professor John Merrill. "If those mid-latitude storms aren't here as often, average wind speeds will decrease."

They also note that ground features such as unevenness, buildings and trees also affect wind speed. For ground-based wind generators, height is the key factor to increasing efficiency. "If the anemometer height is at about the same level but everything else is growing up around it, like buildings and forests, that would create surface roughness or drag that could decrease wind speeds," said graduate assistant Kelly Knorr, an ensign in the U.S. Navy assigned to URI to earn a graduate degree.

Charlestown’s own MET tower wind data underscores that point. In Ninigret Park, it’s located even closer to the water in a more favorable location than LeBlanc’s proposed site north of Route One on the Charlestown moraine near King’s Factory Road. The Ninigret Park data shows that even at 161 feet off the ground, the average wind speed is only 9.31 knots, barely within the range of practicality for an industrial wind turbine.

At 95 feet above ground, average wind speed drops to only eight knots.

This new data would certainly be available to any investors or lenders LeBlanc might approach for funding for the Whalerock project, should he prevail in the courts.

Click here to see the numbers and charts from one year’s worth of data collection at Ninigret Park.

The URI team says that if the trends shown in their data continue, it may curb development of land-based wind generation in southern New England across the board, while boosting more offshore development.

"The Department of Energy wants the U.S. to have 20 percent of its electricity generated from wind power by 2030, but if this trend of declining wind speeds is widespread across the country, then that could have a significant effect on the future of wind energy here," said Knorr.

"Wind speeds at inland sites are much lower near the ground because of the greater drag at the surface, but there is much less drag the higher you go, so speeds can really pick up," Knorr said. "Over the ocean, wind speeds start out stronger at the surface because there's less drag, and it doesn't increase as quickly the higher you go."

This report, combined with Charlestown wind speed data from the MET tower in Ninigret Park, supports my theory that LeBlanc isn’t really serious about actually building the wind farm, but is using it as leverage to get the town to buy his land.