"Our job is to see the marketplace has choices that are as economical as possible," Moniz said. "Our job is not to pick market shares; it's to provide choices."
Although viable clean-coal technology for power plants could be 15 years from deployment, Moniz said the work must be done now to keep coal competitive.
Coal consumption is up this year over 2012, he said, because rising gas prices made it competitive.
"The market is doing a little rebalancing," Moniz said.
The U.S. has doubled production of wind and solar power in the past four years, he said, yet coal and other fossil fuels account for 80 percent of all energy production and 70 percent of electricity production. That makes the need to innovate critical.
The Energy Department "is going to be the place to be over the next few years, as far as challenges go," he said, comparing the work ahead to natural gas research done in the 1970s that helped spawn the ongoing boom in deep, unconventional shale-gas drilling.
"It takes time to see the results," Moniz said, "but boy, are we seeing them in spades today for our economy."
Government-led gas research had several critical components that Moniz said also must apply to coal: Public-private partnerships with universities and industry; demonstration projects; and limited-time tax incentives to apply new technologies.
"We need to do more of this," he said.
Moniz said the Energy Department also needs to work closely with states and regions, all of which have different needs, resources and regulatory structures, because one-size-fits-all approaches to climate change won't work.Some states, for example, may want to focus on energy efficiency, he said, or changing consumer habits to reduce their consumption. McKinley, he noted, is advocating such legislation in the House, and many states have done work in that area that could help the federal government.