The Illinois House was scheduled to consider an energy bill on Thursday that could prevent power company Exelon from permanently shutting down four nuclear reactors at two sites, starting in the coming days.

“I am pleased to see negotiations moving forward on a comprehensive energy proposal that prioritises a greener future for Illinois, as well as meaningful ethics reform and maintaining our current workforce,” House Speaker Emanuel Welch, a Democrat, said in a statement on Tuesday.

On 1 September the Illinois Senate passed a bill that contains more than $600m in carbon mitigation credits for nuclear plants, which generate virtually emissions-free electricity.

The state has been working on the bill for nearly two years but it has been delayed on concerns of governor J.B. Pritzker, a Democrat, some lawmakers and environmentalists that coal plants would not be phased out quickly or allowed to keep running with unproven carbon-capture equipment.