Federal Energy Regulatory Commission Chairman Neil Chatterjee took a break from discussing a high-profile plan to prop up coal and nuclear plants to criticize environmentalists' efforts to delay pipeline approvals.

"I understand the significance of that proceeding to everyone in this room, particularly our press friends in the corner, but as you know much has been written on this topic already," Chatterjee told a natural gas industry luncheon in Washington. "It is a topic that has consumed much of the oxygen in the room over the past several weeks."

The plan looks to provide coal and nuclear plants with market-based incentives that would reward their ability to keep the lights on when the grid is significantly strained. The plan faces major opposition from oil and natural gas producers to the wind industry.

Instead, Chatterjee used his remarks before the Natural Gas Roundtable to slam what he called the well-funded and legally savvy campaigns by climate change activist groups to significantly delay the natural gas pipeline approval process at FERC.

The independent federal agency is in charge of overseeing the development of interstate oil and natural gas pipelines. Activists have targeted natural gas pipelines because of the perceived link between the drilling process known as fracking and pipeline development. The activists equate stopping FERC with stopping the fracking process since pipelines are the only way to transport shale-produced natural gas to the market.

"It is not hard to see that opposition to natural gas pipeline projects has become much more ideologically driven than it used to be," Chatterjee said.

He said much has changed from when pipeline decisions might have been held up by local interests, such as a landowner or community, which focused on avoiding pipelines being built on their land. But anti-fossil fuel activism has turned pipelines into a much bigger issue that is slowing the agency's work.

"But what's new is this: increasing anxiety about carbon emissions has given rise to a national 'keep it in the ground' movement resisting any natural gas project as a matter of principle," Chatterjee said.

The FERC chairman said the movement is reminiscent of the nuclear power plant protests of the 1970s and '80s, but with “greater” financial backing and legal sophistication.

There has been a "sea change in the identity, volume and goals of stakeholders participating in our proceedings, as well as in the nature and tone of the rhetoric of those who oppose pipeline projects."

Adding to the national activist groups are the "political branches" of state and federal governments that "these pipeline opponents" now possess, alluding to members of Congress and state attorneys general that look to block fossil fuel development.

"Now, what we see are well-funded, sophisticated, national environmental advocacy organizations who understand how to use all of the levers of federal and state law to frustrate pipeline development," Chatterjee said.

He particularly noted the "clever" legal strategies employed by activist groups to confound the natural gas pipeline review process at FERC. Even if they do not win lawsuits, they manage to significantly slow the pipeline review while emboldening state opposition to pipeline development, he said.

The FERC chairman also said it has become increasingly "evident that these folks are growing more confident in their chances in taking those challenges to the D.C. Circuit, in particular, and other federal appellate courts."

Chatterjee said that affects FERC by forcing the agency to become "even more deliberate in its review processes to ensure that they will withstand judicial review."

He said the commission is looking for ways to help speed up the pipeline approval process even as outside forces are increasing their opposition.