The U.S. is at a “tipping point” with its fading nuclear power sector, and the industry’s future is increasingly reliant on developing small nuclear reactors, a top Energy Department official said Tuesday morning.

“We are in an extremely challenging moment in time, an inflection point in terms of the future of our nuclear fleet,” said Ed McGinnis, principal deputy assistant secretary in the Department of Energy’s Office of Nuclear Energy.

“I would say we are at a tipping point,” McGinnis testified at a hearing of the House Energy and Commerce Committee. “Our ability to bring new reactors in the pipeline is key.”

McGinnis cited the importance of NuScale Power’s planned 50-megawatt small reactor, which he called “game changing.”

The company is close to licensing a new reactor design for commercial use. The smaller reactors would be cheaper to create, contain less fuel and energy, and operate with less risk of accidents, NuScale says.

“The U.S. is still the leader in the design and development of advanced reactors, bar none,” McGinnis said. “We are challenged in deployment. It’s an exciting time if we can figure it out.”

McGinnis also said the Energy Department is looking at hybrid plants that would combine small nuclear reactors with wind and solar.

"We don't use the word game changer lightly," he said.

The Nuclear Regulatory Commission’s estimated 40-month review for the NuScale design that began last year is "progressing on the established schedule," said Victor McCree, executive director of operations for the agency.

NuScale, an Oregon-based nuclear technology firm, is hoping to be the first company in recent decades to obtain a license to operate a new reactor design in the U.S. for commercial use.

The Energy Department has invested $226 million in NuScale since 2013.

A group of utilities in six Western states hopes to connect 12 of the NuScale reactors together for use in Idaho to create a 600-megawatt power plant.

The company says it is considering more projects in Washington, Utah, Wyoming, New Mexico, and Arizona.

Nuclear power, which is carbon-free, supplies 20 percent of the country's electricity.

Today, 60 percent of the carbon-free energy produced in the U.S. comes from the nation's existing 99 nuclear power plants.

But the number of reactors is declining, from a peak of 104 in 2012, with several scheduled to be decommissioned soon.

Lawmakers at the hearing said they supported the Energy Department’s hopes for advanced nuclear reactors.

“If our country is going to meet its carbon reduction goals, then nuclear energy may still need to be a part of the solution for a while,” said Rep. Frank Pallone of New Jersey, the top Democrat on the committee. “While I do not think the federal government should be subsidizing nuclear plants in competitive markets, it is important we invest in research into advanced nuclear reactors that can potentially generate power more efficiently, with less waste than our current reactor fleet.”