The plight of an Ohio power provider that plans to close three of its nuclear plants is dividing clean energy supporters and environmentalists, who debate whether carbon-free nuclear is worth saving or if wind and solar are ready to pick up the slack.

The impending closure of three of FirstEnergy’s nuclear plants in Ohio and Pennsylvania — and the broader financial struggles of the nuclear industry — presents a challenge to U.S. efforts at lowering greenhouse gas emissions that many scientists say contribute to climate change because nuclear doesn’t emit any greenhouse gases.