By William Opalka

NEWTON, Mass. — Large hydropower projects shunned by New England’s renewable portfolio standards are elbowing their way into the clean energy conversation, speakers at the 13th Northeast Energy and Commerce Association Conference on Renewable Energy said Thursday.

Hydropower projects larger than 30 MW have not qualified for financial incentives under most New England states’ standards.

But with coal and nuclear fleets shrinking, large-scale Canadian hydropower is needed to avoid an overreliance on natural gas and meet aggressive carbon reduction goals, several speakers said. Wind and solar can’t develop at scale fast enough to replace thousands of megawatts of legacy generation, they said.

“If we’re going to achieve our climate and clean energy goals under the [Massachusetts] Global Warming Solutions Act and the various states’ renewable energy targets, we’re going to need a course correction,” said Leslie Malone, a senior analyst at the energy and environmental organization The Acadia Center.

The Massachusetts law and similar legislation in Connecticut mandate a 25% cut in greenhouse gas emissions from 1990 levels by 2020 and an 80% reduction by 2050.

One potential solution, Malone said, is a “bundling” of firm hydro resources with intermittent wind energy to create a steady supply of clean power into the region.

Natural gas accounts for about half of the region’s power mix, with that percentage expected to grow. ISO-NE estimates 4,200 MW of older generation will retire in the next few years, including the 1,517-MW coal-fired Brayton Point station and the 680-MW Pilgrim nuclear plant, both in Massachusetts.

Most of the new plants that have cleared in ISO-NE’s recent Forward Capacity Auctions are natural gas generators.

David Wilby, senior vice president for state policy at SunEdison, noted that the pace of plant retirements has been faster than added capacity in recent years. SunEdison began as a solar energy developer, but in 2014 it acquired Boston-based First Wind, a developer of wind projects from Maine to Hawaii.

“As much as my company and others have added renewable megawatts as quickly as we can, we’re basically treading water … so we need big, large long-term investments to grow and to help the [power source] diversity,” he said.

The proposed Northern Pass transmission project in New Hampshire would bring 1,090 MW of Canadian hydropower into the market. (See Vermont OKs Canadian Hydro Line.)

But those projects aren’t enough to replace the retiring generation, said David O’Connor of ML Strategies, a government relations and consulting firm.

Massachusetts Gov. Charlie Baker’s proposed legislation to authorize utilities to purchase 2,400 MW of large-scale imports also is insufficient, he said. “That would be … about one-third of Massachusetts’ needs, or only 10% for the entire region,” he said. (See Baker: Hydropower Contracts Best Way to Lower Costs.)

The region’s clean energy needs are sufficiently large that Canadian projects are no longer seen as crowding out local resources, Wilby said. “It’s not hydro, or wind, or renewables; it’s ‘and’ to get us where we need to go,” he said. “It’s not one thing that’s going to get us there.”