At least five major transmission projects — some estimated to cost more than $1 billion to build — have been proposed to connect New England to this plentiful power source to the north. The projects, however, are not only spurring opposition in the communities where the lines would cross but also a broader debate about the region’s energy policy and the role hydroelectricity should play.

Across the Canadian border, massive dams generate a seemingly endless supply of hydroelectricity — a source of power that could help New England replace its closing coal and nuclear plants while cutting greenhouse gas emissions that contribute to climate change. But there’s a big problem: getting it here.


That debate flared again last week as New England governors met with the leaders of eastern Canadian provinces in New Hampshire to discuss energy and economic issues. Opponents of a hydro transmission project that would cross wilderness areas in New Hampshire, the so-called Northern Pass, staged protests; so did opponents of a proposed pipeline to transport natural gas from shale fields in Pennsylvania and other nearby states across Massachusetts.

These protests underscored the challenges policy makers face as they try to balance growing demand for energy against increased urgency to slow the pace of climate change, which scientists attribute to the use of fossil fuels such as coal, oil, and natural gas. While solar, wind, and other renewables are certain to play larger roles in the region’s energy mix, they remain intermittent power sources without the scale to easily replace the more than 4,000 megawatts of generating capacity, or enough to power 4 million homes, that will be lost over the next few years with the shutdown or planned shutdown of three coal-fired plants in Massachusetts, a nuclear plant in Vermont, and other facilities in New England.


With ISO New England, the region’s grid operator, forecasting potential shortages by 2017, policy makers are looking to Canadian hydro — and so are utilities hoping to profit by transporting the power south. The proposed transmission projects include:

■ Northern Pass, a $1.4 billion, 187-mile transmission line pushed by Northeast Utilities that would bring power from Canada’s Hydro-Quebec into Southern New England.

■ The New England Clean Power Link, a $1.2 billion, 154-mile project that would run from the Canadian border under Lake Champlain to Ludlow, Vt.

■ The Northeast Energy Link, a joint project of National Grid and Bangor Hydro that would build a 230-mile line from Orrington, Maine to Tewksbury, to bring power from Canada and Maine.

■ The Green Line, a 350-mile cable that would transport wind power from Maine and supplementary hydroelectricity from Quebec and the Canadian Maritimes.

■ And the Grand Isle Intertie, a 60-mile line that would bring wind power from northern New York, under Lake Champlain to Vermont, and supplement it with hydro from New York and possibly Canada.

It’s unclear which projects ultimately will be built.

“Hydro is a very critical part of the plan,” said Barbara Kates-Garnick, undersecretary of energy in Massachusetts. “It’s clean, it’s available, and there are hydro projects being developed.”

Hydroelectricity accounted for just 7 percent of New England’s net electricity generation last year, according to the US Energy Department, compared with nearly 50 percent for natural gas-fired plants. But hydropower remains controversial.


Political and environmental leaders have struggled with whether to classify large-scale hydroelectric operations as clean sources of power, since their dams inundate large swaths of land, eradicate natural landscapes, and disrupt or destroy both land-based and aquatic ecosystems.

Environmentalists also worry that easy access to low-cost hydroelectricity will undermine the competitiveness of emerging alternative energy technologies and slow or derail their development. Hydropower, including maintenance, operations, and other costs, runs about 2 cents per kilowatt hour, about one-third the price of electricity generated with natural gas, according to a 2010 study by Navigant Consulting of Chicago.

Peter Shattuck, director of market initiatives at the advocacy group Environment Northeast, said policy makers must think beyond what may seem quick fixes to energy and climate challenges to support emerging technologies that could provide long-term solutions.

“You need to hit the pause button and say we recognize the need to look at the alternatives, ” Shattuck said.

Such concerns have increased as New England states consider legislation to give large-scale hydropower projects clean-energy preferences similar to those for wind and solar. Connecticut already has adopted a law that allows utilities, in certain cases, to count electricity from large-scale hydro projects toward state mandates for acquiring power from renewable sources.

Lawmakers in Massachusetts are considering similar measures. One bill would require the state’s investor-owned utilities to buy 2,400 megawatts of clean energy, which, for the first time, would include hydropower. State Senator Barry Finegold, an Andover Democrat who co-sponsored the bill, said the goal is to become less dependent on natural gas.


“Whether it’s hydro, wind, solar, we want to have more diversity,” Finegold said.

New England power plant owners, however, say the bill would give unfair preferences to Canadian hydropower. They say the costs of building transmission and related projects would quickly overwhelm the lower hydropower price. “It’s an irresponsible use ofonsumer dollars,” said Dan Dolan, president of the New England Power Generators Association, a Boston-based trade group.

Still, as Massachusetts and other states race to meet goals for cutting greenhouse gas emissions, the opportunities appear big for hydropower. In Ayer, National Grid’s Sandy Pond transmission station already connects to hydro projects in Northern Quebec.

Mary Ellen Paravalos, National Grid’s director of strategy and business performance, said New England needs to build more transmission to meet electricity demand, whether it comes from hydroelectric dams, wind farms, or other resources. She noted the three generators that have or will soon shut down: Vermont Yankee nuclear plant in Vernon, Vt., scheduled to close later this year, and two coal plants, Salem Harbor in Salem, which shut down in June, and Brayton Point in Somerset, scheduled to close in 2017.

“Those are closing right now when we’re thinking about how to get more power to the region,” she said. “You have to assess the options. You need a pipeline of projects.”


TDI New England, which is developing the Clean Power Link from Canada to Vermont, hopes to start construction by 2016. Donald Jessome, TDI’s chief executive, said he expects the project to benefit customers by providing access to lower-cost energy.

“We’re already talking to multiple hydro providers in Canada,” Jessome said. “We’re actually talking to wind providers as well.’”

Any new transmission should integrate solar, wind, and other renewable energy into the power grid, said Seth Kaplan, vice president for policy and climate advocacy at the Conservation Law Foundation, a environmental advocacy group in Boston. As policy makers pursue a bigger role for hydro, he said, they must maintain commitments to alternative technologies.

“New England is only going to build a relatively limited number of these transmission lines — that’s just a reality — and we need to make sure that when we take one of those few shots that we are trying to achieve all of our [energy] goals,” Kaplan said. “Therefore, lines that would combine together wind and hydro are particularly attractive.”

Erin Ailworth can be reached at erin.ailworth@globe.com. Follow her on Twitter @ailworth.