Waterford — The Connecticut arm of the American Association of Retired Persons says Dominion Energy should be more transparent in its effort to prove the Millstone Power Station needs state support to survive.

In a letter to regulators Thursday, AARP Connecticut backed motions from the state Office of Consumer Counsel, an independent advocacy group, and power company NRG, which both called on Dominion to provide harder public evidence demonstrating Millstone suffers in the current energy market.

"At a minimum the company should identify document titles and provide redacted copies," AARP wrote. "Dominion needs to open its books to explore its claims that its Millstone plant is unprofitable."

Dominion recently handed over two confidential exhibits to the Department of Energy and Environmental Protection and the Public Utilities Regulatory Authority. The agencies are examining Millstone's finances along with potential energy market changes that Dominion and local officials say are vital to prevent premature closure.

DEEP and PURA consented to Dominion's request to keep the financial data secret. Dominion says the information backs up its claim that Millstone suffers from competition with low-cost natural gas, despite publicly available data and regulators' analysis showing the plant remains substantially profitable.

"It's clear globally the industry is facing challenges and Millstone is in that same boat," Ken Holt, Millstone spokesman, said recently.

Asked about AARP's support of NRG's and OCC's recent filings, Holt said Thursday that Dominion opposes NRG's motion. NRG called on Dominion to identify what it turned over to regulators and provide public redacted copies of the confidential filing.

"This is a transparent attempt by one of our competitors to get access to our data," Holt said. "This motion reinforces how valuable the data we've provided to the state is and how hungry our competitors are to get ahold of it."

Dominion and many local officials are pushing for energy market changes, recognizing nuclear power generation as a low-carbon source of energy, to let Millstone compete in a state bidding process alongside wind, solar and hydropower.

For months, the company declined to provide regulators proprietary financial data, claiming it could give competitors an edge.

But after Gov. Dannel Malloy signed a bill in October allowing officials to include nuclear in the state bidding process along with renewables, pending regulators' recommendations in February, Dominion engaged in private talks with DEEP and PURA and shared two "high-level financial projections of costs and revenues for Millstone" on Nov. 30.

But like NRG, which has fought state proposals that would benefit Millstone, AARP believes regulators should demand Dominion provide more detailed information and redacted documents to the public.

"If you're a prosecutor, how do you try a case when you don't know all the evidence?" John Erlingheuser, advocacy and outreach director for AARP Connecticut, said in an interview.

In a filing Thursday, Dominion said NRG offered no basis for its contention that documents were "somehow being 'inappropriately shielded from the public.'" The company noted DEEP and PURA "approved the request for complete protective treatment."

AARP also backed the Office of Consumer Counsel's request to view the documents in question.

Earlier this month, OCC argued it had "the absolute right" under state statute to view any PURA documents containing data that directly could impact Connecticut's electricity consumers.

Holt said Dominion does not oppose OCC accessing the financial data provided to regulators, as long as it abides by a protective order barring any public disclosure.

After a public hearing in Waterford on Tuesday, where most speakers supported Millstone, DEEP Commissioner Rob Klee said regulators would continue engaging with Dominion over the confidential financial data. Another hearing was held in Hartford on Wednesday.

Klee and other officials said the final report would reveal whether the data was sufficient to help persuade regulators to recommend the energy market changes sought by Dominion.

"Over the past two days of public hearings, we have listened to a wide range of opinions regarding the draft report, and we will take them into consideration before we issue the final report in February 2018," Chris Collibee, DEEP spokesman, said in an email.

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