Using zinc to build just 1 km (0.6 miles) of road saves $31 million and 3,000 tonne (3,306.9 ton) of carbon emissions in avoided repairs and replacements, according to new research from the Zinc Enables Decarbonization (ZED) program.
The latest ZED study finds that building with galvanized, or zinc-coated, steel rebar used to reinforce concrete results in massive savings in both costs and carbon emissions. The ZED initiative is a partnership between the International Zinc Association (IZA) and environmental economist Dr. Benjamin Cox, program director of the Bradshaw Research Institute for Minerals and Mining at the University of British Columbia.
“Building with galvanized rebar creates strong infrastructure designed to last for generations,” says Dr. Andrew Green, executive director of the IZA. “By protecting steel from corrosion, zinc increases safety, decreases costs, and reduces future carbon emissions.”
The new ZED report quantifies zinc’s value in infrastructure and measures the economic and environmental value zinc brings in the construction of roads, sewer mains, and pedestrian walkways. Using galvanized rather than ungalvanized rebar adds less than 1 percent to construction costs yet saves millions in repairs and replacements, including $600,000 for a 1 km (0.6 miles) pedestrian walkway, $4.4 million for a 1 km (0.6 miles) sewer main, and $31 million for a 1 km (0.6 miles) road.
ZED economist Dr. Benjamin Cox found that galvanized zinc can increase the service life of various infrastructure projects by a span of 30 to 100 years.
“Building with zinc isn’t new; what is new is quantifying the tremendous economic and environmental savings zinc brings to any type of construction,” says Dr. Cox. “In addition to reduced costs, building with zinc prevents the carbon emissions associated with extracting, manufacturing, and transporting materials for early repairs and replacement that occur when zinc isn’t used in construction. Just one project with galvanized rebar prevents hundreds or thousands of tonnes in carbon emissions. Imagine the impact if 10 percent of transportation infrastructure was built using galvanized rebar.”
“From millions of dollars to millions of tonnes of carbon emissions, zinc offers a clear solution to reducing our carbon footprint,” says ZED director Dr. Eric Van Genderen. “Galvanized rebar has been used for a century, but now that we understand the true value zinc brings through galvanized rebar, we can make the case to policy makers, investors, engineers, builders and insurers that zinc should be a permanent part of infrastructure planning.”
