After years of attempts to open Colorado up to nuclear energy, a bill before the legislature this year is showing new promise for the effort.

In an annual ritual, Sen. Larry Liston, a Colorado Springs Republican, has regularly introduced legislation that would add nuclear energy to the state’s definition of clean energy sources. Only this year, in a marked break from prior bills, the proposal, House Bill 1040, has drawn bipartisan support — a key hurdle in a building where Democrats outnumber Republicans nearly 2-to-1.

Nuclear technology has improved enough to minimize the concerns of yesteryear, Liston argues — and it could fill a critical gap as Colorado moves away from carbon-spewing fossil fuels. Explicitly classifying nuclear as clean energy could qualify it for new grants. The bill, if passed, would not immediately kick-start any new nuclear development, but it could put some momentum behind the concept.

Liston said he never saw his nuclear interest as a partisan issue, but rather as one of educating people about how the nuclear industry has changed.

“It’s nothing like what people think of, with Chernobyl and Three-Mile Island and the technologies of 40, 50 and 60 years ago,” Liston said, referring to nuclear meltdowns in 1986 and 1979, respectively. “Those types of nuclear plants won’t be built, at least here in Colorado.”

He points to new technologies like small modular reactors that have relatively small footprints and molten salt reactors that don’t use water as a coolant in energy production. And, of course, he highlights the constant stream of energy, with zero carbon emissions, that they could provide.

Nuclear energy accounts for about 18% of the United States’ total energy production, according to the World Nuclear Association, making it the single-largest source of non-fossil-fuel electricity in the country. Natural gas and coal account for about 60% of the energy mix.While other countries may rely more on nuclear power, the scale of the U.S. energy market means it produces the most nuclear power of any country, according to the association. That’s true even as construction on new nuclear plants effectively was halted for more than 30 years following the Three-Mile Island accident and amid the rising economic viability of other energy sources.

Rep. Alex Valdez, a Denver Democrat carrying the bill in the House, said his support grew while he was looking for “creative ways” to meet the state’s ever-growing electricity demands — not just from households and electric cars, but from industrial needs, like data centers for emerging technologies.

“There’s been such a dramatic increase in demand that we expect to continue here in the state of Colorado for quite a while,” Valdez said. “We need to do everything we can to keep up with that demand while being mindful of air quality and pollution and all the things that are really important to people all along the Front Range and through Colorado.”

The other sponsors, Democratic Sen. Dylan Roberts and Republican Rep. Ty Winter, also raise concerns about the workforce as the state transitions away from fossil fuels, chiefly coal. Roberts, from Avon, and Winter, from Trinidad, represent areas that are set to be among those hardest hit by the move.

“In addition to other sources of alternative energy, like geothermal and pumped hydrogen, adding nuclear to this list and allowing it to count toward our carbon emission-reduction goals is a way to attract more attention and potential investment into the region,” Roberts said.