House Bill 6 has been described as the most significant overhaul of the state’s energy laws in a decade. And that is the problem. The Republican majorities missed an opportunity. They had the chance to update the state’s energy efficiency and renewable energy standards, putting Ohio in a stronger position to prosper in the emerging clean economy. They could have reinforced the boost to public health, one study projecting the net benefit of the renewable portfolio standards at $170 million in 2030.

Instead, the bill, signed by Gov. Mike DeWine on Tuesday, all but guts the standards. Gone is the quest for 12.5 percent of electricity coming from renewable sources by 2026. The threshold now is 8.5 percent, and that requirement will disappear in seven years. The energy efficiency standard, electricity use reduced 22 percent by 2027, will end, essentially, at the current 17.5 percent. This is not surprising. Republican lawmakers long have worked to undermine the standards.

Ohio has taken a step back, compared to other states in pursuing the clean economy, a sector that under the standards has helped to generate 112,000 new Ohio jobs. That isn’t to say the standards are ideal. There are other ways to spur the clean economy. The Environmental Defense Fund has proposed setting a statewide ceiling on carbon emissions that would apply a steadily tighter limit, allowing the marketplace to sort through how the state would get there.

The Republican majorities have offered no such substitute. At the same time, they have moved forward with a continued subsidy for two aging and outdated coal-fired power plants, under the shared ownership of utilities in the state.

Recall the energy summit conducted by John Kasich early in his tenure as governor. Whatever the many shortcomings of that effort, it looks bold and visionary compared to what the Statehouse has produced this week.

Yet House Bill 6 does accomplish something important for the state — and the planet. It puts the Davis-Besse and Perry nuclear power plants in position to keep operating. That’s 90 percent of the clean energy generated in the state, and worth the 85 cents a month residential ratepayers will be charged, all told $150 million a year going to FirstEnergy Solutions, the still-in-bankruptcy owner of the nuclear plants. Lose that power, and carbon emissions would climb, renewable and other clean sources unable to make up the difference until the 2030s, or too late given advancing climate change.

Be sure, carbon-emitting natural gas, cheap and abundant, would fill most of the void.

It follows that FirstEnergy Solutions struggles to compete. The market favors natural gas. That explains why nuclear plants more widely are in financial trouble. Yet, in this case, there is more at stake than the lowest price. There is social value in reduced carbon emissions.

Much of the legislative debate involved a battle of cost-estimates, each side insisting its course would be less burdensome for consumers. Overlooked is the much greater expense of climate change, apparent already in farmers unable to plant because of heavy rains, flooding in communities and a deepening understanding of the big investment required to repair and adapt. Nuclear power plants are indispensable to an adequate response.

Unfortunately, in this debate, too many environmental groups and allies have appeared blind to this reality — the true threat of catastrophic climate change. With Davis-Besse and Perry, there is less carbon in the atmosphere. There also is the fortunate outcome for communities surrounding the plants, saving some 1,400 jobs, plus the flow of tax revenue. The governor and lawmakers acted responsibly in coming to the aid of nuclear power.