Proponents of House Bill 6 talked initially about providing incentives to build and maintain clean sources of energy. They even framed the effort as part of shrinking the state’s carbon footprint. In its latest version, approved in committee on Thursday, the legislation still makes a significant contribution toward those goals. It seeks to preserve 90 percent of the state’s clean energy, the Davis-Besse and Perry nuclear power plants, owned by FirstEnergy Solutions, which is looking to emerge from bankruptcy.

Yet the bill also is a big disappointment. It squanders an opportunity to promote clean energy as an environmental and economic benefit to the state.

As originally conceived, the legislation created an Ohio Clean Air Program, a ratepayer-supported fund largely designed to support carbon-free energy sources, including wind and solar power. Roughly half of the money would have flowed to the financially strapped nuclear power plants. Yet renewable sources would have been eligible, too.

The bill would have been improved by making access for renewable sources less restrictive. Unfortunately, the legislation now is worse. Renewable sources no longer would be eligible for the program. More, the bill wipes out the state’s renewable energy standard, designed to increase the role of solar, wind and other clean sources in supplying electricity.

Backers of the legislation faulted environmental groups for showing little interest in participating in the program. If so, that hardly is reason for excluding renewable sources, especially in view of the real potential in the clean economy. As it is, this latest version smacks of the misguided hostility the Republican majorities long have expressed toward the renewable standard.

Such a standard is far from ideal, as recent research shows. Ohio would do more to promote clean energy by setting an overall limit on carbon emissions, the permitted amount narrowing with each year. Still, the standards are better than nothing. Which, essentially, is where the state would stand under the current version of the bill.

Actually, the legislation represents a step back. It includes provisions that would work to bolster the financial position of the two Ohio Valley Electric Corp. coal-fired power plants, co-owned by several utilities. The story of the plants is complicated. They supplied electricity to the now-closed uranium enrichment plant near Piketon. Yet this isn’t the time to subsidize such sources of carbon emissions.

That gets to the redeeming feature of the Davis-Besse and Perry nuclear plants as proven sources of clean energy. Lose their presence, and it would be the 2030s before renewable sources make up the difference, let alone expand the carbon-free portfolio. That is why many climate scientists at this point see nuclear power as crucial in curbing climate change, the destructive effects already mounting, the state, country and globe without a clean megawatt to spare.

Thus, it is worth repeating that the subsidies for Davis-Besse and Perry involve more than the “bailout” critics decry. As effectively as markets operate, they also often are flawed, in particular in failing to assign social value.

Nuclear power plants face financial challenges because the market favors abundant and cheap natural gas. The market doesn’t account for natural gas emitting carbon and fueling climate change. If it did apply such a price, nuclear would be more competitive. So that is the role of the subsidy, serving to level the playing field, advancing the larger social cause of reducing carbon emissions, not unlike the credits and other incentives directed to renewable energy sources.

So it is smart to keep nuclear power plants generating electricity. What isn’t clever is the opening missed in this version of House Bill 6, the Republican majority proving short-sighted about the climate and the state economy.