In a statement, Nucor said it already has one of the lowest carbon footprints among steel companies, but it will nevertheless commit to an additional 35% combined reduction in the Scope 1 and Scope 2 greenhouse gas emissions intensity of its steel mills by 2030.

The commitment will be measured against a 2015 baseline, Nucor said. 

Nucor said its greenhouse gas emissions stand at 0.47 ton of CO₂ per ton of steel. That compares to a global average of 1.69 tons of CO₂ per ton of steel and an integrated steelmaking average of 2.15 tons per ton of steel, it said. By 2030, Nucor's steel mill greenhouse gas emissions intensity will be 0.38 ton of CO₂ per ton of steel, the company said.  

"The green economy is being built on steel. As an electric arc furnace steelmaker and North America's largest recycler, Nucor is already a world leader in sustainable steel. Our greenhouse gas intensity is less than one-third the world average, but we are committed to going further," said Nucor president and chief executive Leon Topalian.