The Sierra Club has filed a lawsuit demanding that the Department of Energy reveal who it’s been consulting with as the agency rewrites a critical grid study looking at whether wind and solar are impacting reliability.

The lawsuit filed Monday in U.S. District Court for the Northern District of California demands that the DOE disclose all communications between staff members working on the study and coal and nuclear power plant groups, including the Edison Electric Institute (EEI).

It also requests communications between DOE and grid operators, as well as the Federal Energy Regulatory Commission, “to see to what extent DOE is trying to exchange information with these entities, which have a lot of experience and a lot at stake” in the outcome, Sierra Club Senior Attorney Casey Roberts said in a Monday interview.

The Sierra Club first requested these communications in a May 1 Freedom of Information Act application, and filed the lawsuit after the DOE failed to respond to it within the 20-day period set out in the law. “It’s not unusual for agencies to take a little more time" than 20 days, Roberts said, "but this has been three months, and we have an urgent need for the documents."

That’s because the study, ordered by Energy Secretary Rick Perry in April, is “the focus of heightened suspicion from clean energy job creators, policy experts, and members of Congress as a ploy by the Trump administration to pressure grid operators and FERC to put in place rules that force electricity customers to bail out old, expensive coal and nuclear plants,” the Sierra Club wrote.

These concerns began with Perry's letter ordering the study, which indicated that wind and solar power subsidies should be considered as a contributor to the increasing number of coal-fired and nuclear power plants closing across the country.

They were heightened in May when Perry told a conference audience in New York that the federal government may seek to interfere in state renewable energy portfolio standards and other policies to shore up “baseload” power.

These views fly in the face of industry, government and academic analyses that point to cheap natural gas as the key factor in making coal and nuclear power less competitive.

Perry's assumptions contradict the DOE itself.

In July, a draft version of the grid study leaked to the press noted that natural-gas power plants, not wind and solar policies, were the key challenges for coal and nuclear power plants. It also cited multiple studies indicating that the grid could handle the current and forecast rates of baseload power plant retirements, as well as increasing penetration of intermittent wind and solar power, largely through reliance on expected natural-gas supplies.

It's far from clear whether these findings will make it into the final report, however. Shortly after the draft study was leaked, a DOE spokesperson told Bloomberg that a key paragraph absolving solar and wind power from responsibility for destabilizing the grid was “not in the current draft,” which she called a "work in progress."

The report is back behind closed doors. And onlookers are waiting to see how different the new version is from the leaked version.

“There’s significant public interest in the outcome of this study,” Roberts said. While the DOE doesn’t interact directly with how the country’s grid operators and federal regulators implement grid policy, “there’s ongoing discussion at FERC and at grid operators around the resilience of the grid,” she said.

The Sierra Club has singled out communications between the Edison Electric Institute and the DOE grid study team, given that Perry’s chief of staff, Brian McCormack, previously worked for the utility trade group, Roberts said.

“We hope that DOE will give us the documents,” she said. “If they give us a complete response, we will withdraw the lawsuit. If they don’t, the parties will bring the issue to the judge about whether DOE has violated FOIA’s deadlines.”

Didn't catch the leaked report? Listen to Shayle Kann and Stephen Lacey dissect its contents -- and its consequences -- in a recent episode of The Interchange podcast.