Submitted by the American Institute of Steel Construction
Bill Gates has been traveling the country promoting his new book, How to Avoid a Climate Disaster: the Solutions We Have and the Breakthroughs We Need, and one of his key points is that the cement and steel industries contribute more than 10% of the world’s greenhouse gas emissions. He correctly points out that our future depends on cutting emissions and calls for the production of cleaner iron ore that can then be used as feedstock for modern, clean, electric arc furnaces to produce steel rather than using older, dirtier integrated steel mills.
Fortunately, America’s structural steel industry began realizing Gates’s dream in 1987. Today, all of the more than 4 million tons of wide flange produced in the United States come from electric arc furnaces. As a result, rather than depending on iron ore, more than 93% of the raw material comes from scrap and the main carbon emissions are from generating electricity, not from producing iron ore and coke.
Unlike other structural materials, steel is not just produced from recycled material, but is 100% recyclable with no loss of material properties.
“Whenever I give presentations to engineers and architects, they’re often surprised to learn that American structural steel contains around 93% recycled material,” said Charles J. Carter, P.E., S.E., Ph.D., president of the American Institute of Steel Construction. “By weight, steel is the most recycled and most sustainable material used in the building industry.”
This is particularly in contrast to wood, which touts its ability to sequester carbon but in reality simply pushes the problem onto the backs of future generations. Unlike a steel building or bridge, which is simply sent back to a steel mill for recycling at the end of its lifespan, when you demolish a wood building the waste is either landfilled or incinerated. In either case, almost all of the carbon is released back into the atmosphere.
To learn more about steel and other structural materials, visit aisc.org/sustainability.