Advancing Low-Carbon Cement Solutions

Cement is one of the most widely used materials in construction, but its production is a major source of greenhouse gas emissions. Cement production accounts for nearly 8 percent of global carbon dioxide emissions. Most of these emissions come from the production of clinker, the main ingredient in traditional Portland cement. Clinker is made by heating limestone at high temperatures, a process that releases large amounts of carbon dioxide.

This project supports the use of alternative cement materials that require less clinker. These materials, known as supplementary cementitious materials (SCMs), include natural pozzolans and reclaimed coal ash. By replacing a portion of traditional cement with these lower-carbon inputs, the concrete industry can reduce emissions while maintaining performance and durability

Carbon credits are issued under the Climate Action Reserve’s U.S. Low-Carbon Cement Protocol, which provides a standardized way to measure and verify emissions reductions from SCM use.

This is a programmatic project with activities occurring at multiple U.S. sites, each listed with the Reserve:

• Kirkland Pozzolan SCM Project — Skull Valley, Arizona
  View project listing (CAR1948)
• Oak Grove Bottom Ash SCM Project — Franklin, Texas
  View project listing (CAR1959)
• Bowen Fly Ash SCM Project — Cartersville, Georgia
  View project listing (CAR2029)
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How the Project Reduces Emissions

• Reduces the amount of clinker required in cement
• Uses natural pozzolans sourced from volcanic deposits
• Reclaims fly ash and bottom ash from legacy disposal sites

Additional Environmental Benefits

• Diverts industrial waste from landfills and ponds
• Reduces potential risks to groundwater
• Improves the long-term durability of concrete
• Supports regional supply chains for low-carbon construction

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