By William Opalka

Massachusetts Attorney General Maura Healey on Wednesday released a study that said additional interstate natural gas pipelines are not needed to guarantee the reliability of New England’s electric grid over the next 15 years.

Instead, reliance on demand response and energy efficiency would protect consumers and also help the region reach its greenhouse gas emissions goals, according to the study.

“This study demonstrates that we do not need increased gas capacity to meet electric reliability needs, and that electric ratepayers shouldn’t foot the bill for additional pipelines. This study demonstrates that a much more cost-effective solution is to embrace energy efficiency and demand response programs that protect ratepayers and significantly reduce greenhouse gas emissions,” Healey said in a statement.

The study by the Analysis Group runs counter to the view of many regional officials that massive pipeline construction is needed as New England becomes more reliant on natural gas for power generation. In October, the Massachusetts Department of Public Utilities ruled that electric distribution companies can sign contracts for natural gas capacity and pass the costs on to electric ratepayers if the companies can prove that they will save ratepayers money. (See Massachusetts Regulators Endorse Pipeline Contracts.)

The authors said the study used “extremely conservative assumptions,” including applying winter conditions from 2004, one of the coldest years in two decades.

“Under the base case analysis, power system reliability can and will be maintained over time, with or without additional new interstate natural gas pipeline capacity,” the report said.

The study concedes additional natural gas infrastructure would lower electricity prices, but with a steep cost. “Investment in new interstate pipeline capacity generates significant wholesale electricity price benefits but would require up-front and long-term ratepayer commitments,” it said.

Analysts also considered the impact of new transmission needed to import Canadian hydropower, the most expensive option for ratepayers, it indicated.

The study accounted for the recent announcement that the Pilgrim nuclear power plant would close no later than June 2019, resulting in the loss of 680 MW of non-GHG emitting power.