In this Tuesday, May 28, 2019 photo a homemade sign is posted on a telephone pole in protest of Central Maine Power's controversial hydropower transmission corridor in Jackman. Credit: Robert F. Bukaty / AP

Central Maine Power and its parent have filed a complaint alleging a competitor opposed to its $1 billion hydropower corridor has illegally obstructed the project by refusing to complete upgrades necessary to connect the project to the regional grid.

It is no secret that NextEra Energy Resources, a large Florida-based utility that operates a clean-energy business in Maine and New Hampshire while also owning the oil-fired Wyman Station plant in Yarmouth, has opposed the New England Clean Energy Connect, the formal name of the proposed 145-mile corridor.

NextEra donated $53,000 to Mainers for Local Power, a ballot question group also funded by two Texas-based natural gas companies to back a now-defunct referendum bid to kill the project, and has been a party to various lawsuits challenging state-granted permits. Supporters of the project have long noted that NextEra stands to lose money if the project is completed.

But the complaint filed this week with the Federal Energy Regulatory Commission by Avangrid, CMP’s parent, goes further, alleging that NextEra refused to complete upgrades at its nuclear power plant in Seabrook, New Hampshire during a planned outage in violation of federal law. That upgrade is necessary to connect CMP’s project to the New England grid.

The two companies drafted an agreement for the breaker upgrades earlier this year, according to the complaint. However, Avangrid alleges NextEra has made “unreasonable” demands in revised copies. They include holding Avangrid liable for all lost profits, revenues and penalties that NextEra would incur from the regional grid operator if it is unable to complete the upgrades.

It also alleges the company has worked through “shadow organizations” to oppose the project, citing “strong circumstantial evidence” that NextEra is tied to them. The complaint names three groups opposed to the corridor, one of which is suing Maine’s campaign finance regulator to prevent donors from being disclosed to staff.

For example, Avangrid pointed to $30,000 in lobbying against the project in the Legislature by Pineau Policy Associates on behalf of one group. The lobbying shop lists NextEra — but not the name of the corridor opposition group — among its clients on its website.

“NextEra has taken every opportunity, both in the open and behind the scenes, to oppose, delay, and derail the NECEC Project, all to benefit its existing fossil and nuclear generation located in Maine and New Hampshire and its renewable projects in Maine,” the complaint reads.

The project, which would run through Maine to pipe electricity from Canada to Massachusetts and the electrical grid, has been the subject of fierce debate for years. It was selected by Massachusetts to meet a massive clean-energy request after a similar project in New Hampshire — Eversource Energy’s Northern Pass — was turned down by regulators.

Two active referendum bids — one opposing the corridor outright and another looking to buy out CMP and another utility — have been launched in recent months, and state permits have been subject to several lawsuits. Millions of dollars were spent opposing a first referendum that was deemed unconstitutional by the state’s high court earlier this year. The project needs federal permits and local approvals to move forward.

The planned outage that Avangrid alleges NextEra is resisting is expected to take place in 2021. Avangrid does not plan another until 2023. Waiting for that replacement would prevent Avangrid from completing the corridor project in a timely manner, according to the complaint. Spokespeople for NextEra did not immediately respond to a request for comment.

Avangrid argues NextEra is using similar opposition tactics it used to oppose the Northern Pass project in New Hampshire. NextEra was suspected to be funding Northern Pass opposition groups in addition to its public and legal opposition.

But NextEra has also appeared willing to temper its opposition, the complaint alleges. An affidavit from Thorn Dickinson, the president and CEO of NECEC Inc alleges NextEra executives have offered to reduce their opposition to the corridor in exchange for an agreement between Avangrid and NextEra for the purchase of power from the Seabrook nuclear plant.

An attached proposal outlines a 15-year agreement between NextEra’s Seabrook plant and Avangrid for energy at a rate of $43.71 per megawatt. It was allegedly sent to Avangrid in September, according to the complaint.