Federal regulators last week signed off on a Japanese company’s plan to buy three gas-fired generators in New England, despite opposition from consumer advocates who had argued that the deal would lead to undue consolidation in the region.

The investment firm Stonepeak asked FERC this summer for approval to sell two units at Canal Generating Station in Sandwich, Mass., totaling 1,457 MW, and another 160-MW unit in Bucksport, Maine, to JERA, a joint venture between two Japanese utilities, Tokyo Electric Power’s TEPCO Fuel & Power and Chubu Electric Power (EC22-71).

Massachusetts Attorney General Maura Healey and the advocacy group Public Citizen had both challenged the acquisition saying that it would give JERA — which already owns 50% of two other gas units totaling more than 400 MW in Massachusetts — too large a share of the generation market. (See Mass. AG, Public Citizen Raise Alarm Over Proposed Generation Deal).

But FERC sided with the buyer and seller, accepting their argument that the transaction would not have an adverse effect on vertical or horizontal competition.

Although JERA will own more than 18% of the capacity cleared in the Southeastern New England zone, FERC wrote that “Applicants’ analysis shows that, when considering ISO-NE as a whole, the proposed transaction does not increase market concentration such that there will be an adverse effect on competition.”

FERC also shot down protests arguing that the deal could have adverse effects on rates and on regulations. And it refused a request from Public Citizen to make public the confidential purchase price of the deal, finding no reason to break with the standard of allowing the submitter to keep prices confidential.