SOUTH PORTLAND — Larger rotors, taller towers and other technical refinements in wind turbine design have unlocked a substantial amount of new wind power potential in Maine and New England, a research scientist from the Lawrence Berkeley National Laboratory told participants at a packed wind industry conference on Wednesday.

This trend in “turbine scaling” means wind power can make economic sense in lower elevations, and in locations that don’t have the highest wind speeds, according to Mark Bolinger. New England has a lot of these sites, he said, such as the rolling hills near Eastbrook in Hancock County, where Boston-based First Wind is now building a 19-turbine project called Bull Hill.

Bolinger’s comments came during the first day of the American Wind Energy Association’s regional summit, which drew roughly 400 people. His optimistic outlook on demand in New England offered a bit of good news for developers and manufacturers who are jittery about the future of tax credits that are crucial to their industry, and are set to expire this year unless Congress extends them. New projects and thousands of jobs that go with them depend on the extension, an association official said.

But the ability to build wind projects in lower terrain isn’t a welcome development for everyone.

Brad Blake, a spokesman for the Citizens Task Force on Wind Power, said most of Maine has marginal wind potential, and the technical improvements Bolinger touted will create more conflicts with people who oppose industrial wind development. The towers at Bull Hill, he said, are 476 feet high and visible from Cadillac Mountain in Acadia National Park.

“We shouldn’t have to sacrifice the mountains of Maine so the industry can squeeze a little more output from their monstrous machines,” Blake said.

With its largely forested landscape and hilly terrain, Maine dominates New England’s wind-energy potential. A total of 19 projects are completed or in development, and the state will have 400 megawatts of installed capacity by year’s end. The potential is even greater offshore, where a pilot project involving floating turbines is being considered.

Lighter and stronger materials are allowing turbine manufacturers to build larger units that create more power, Bolinger said. The average diameter of rotors in New England has grown from roughly 262 feet in 2008, to 328 feet this year, according to data he compiled. The larger diameters can boost turbine capacity from around 2 megawatts to 2.5 megawatts.

These incremental developments are important to the industry because, on an annual basis, unsteady wind speeds limit turbine output to less than 35 percent of its “nameplate” capacity.

In an interview, Bolinger said it’s not likely that manufacturers can improve performance over the next few years at the same pace.

“There are limits,” he said. “And they need to be tested over time.”

Over the next few months, though, much of the industry’s attention is focused on Washington, and the future of production tax credits. The 20-year-old provisions are tied to electricity output and were meant to encourage the development of renewable energy projects. But they’ve come under fire in a political climate where all taxes are under great scrutiny.

Rob Gramlich, the association’s senior vice president for public policy, said the industry is lobbying Congress with this message: The tax breaks won’t be needed forever, but are vital now to save 37,000 jobs. To finance projects and lock down permits, developers need 18 months of certainty on taxes, he said.

That message is getting through, Gramlich said. Last month, the Senate’s Finance Committee passed a package to extend the credit and a related provision for projects that start construction by the end of 2013. The hope now is that, after the election, a lame-duck Congress will extend the credit as part of a broad package of tax issues.

In their criticism of wind power, Blake and other opponents say the wind industry wouldn’t be profitable without government tax breaks. But Dave Wilby, vice president for state policy at First Wind, said the production tax credit was created to let renewable energy compete with coal, oil and natural gas generators, which have enjoyed various tax breaks for decades.

“The energy industry exists only because of government policies,” Wilby said. “There’s this fiction that there’s a free market in the energy business.”

The summit continues Thursday morning, and concludes with a presentation on offshore development in the Northeast.

Staff writer Tux Turkel can be contacted at 791-6462 or
tturkel@pressherald.com