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New Whitepaper Finds that Low Carbon Concrete Mix Designs Show Promise to Decrease CO2 Emissions and Producer Costs 

By SDSN

Introducing a whitepaper, developed by the UN SDSN and Saoradh Enterprise Partners, that evaluates life cycle assessments (LCAs) and cost-benefit analyses for seven low carbon concrete mix designs.

The UN Sustainable Development Solutions Network (SDSN) and a cleantech venture capital firm, Saoradh Enterprise Partners (SEP) , released a whitepaper today analyzing the environmental costs and benefits, while considering the economic impact, of low carbon concrete and cement mix designs. The study compared these designs and identified which were best suited for use based on these environmental and economic factors.

The report conducted life cycle assessments for one cubic meter of concrete and conducted cost-benefit analyses for seven low carbon concrete and cement mix designs produced at an average US batching plant. Mix designs incorporate ground granulated blast furnace slag (GGBS), fly ash, biochar, recycled concrete aggregate (RCA), portland-limestone cement, limestone calcined clay cement (LC3), and early stage carbon curing into the concrete.

The release of this report comes at a critical time. Momentum to decarbonize the second most consumed material in the world (after water) is growing. And rightfully so. Concrete accounts for about 7% of global carbon dioxide (CO2) emissions. If the cement industry were a country, it would emit the third largest amount of CO2 behind China and the US. Furthermore, this $617 billion dollar industry is estimated to grow12 to 23% by 2050. It is the foundation of our world and its utilization is quite concrete.

However, 45% of concrete’s emissions derive from calcination: a thermo-chemical process whose emissions cannot be addressed with go-to solutions like electrification, kiln efficiency, etc. Solutions, such as low carbon concrete mix designs, are essential to decarbonization of this “harder-to-abate” industry.

This study provides insight into an industry riddled with antitrust laws, confidential data, and green washing:

  • All low carbon mix designs, but RCA, offer CO2 emission reductions by up to 43% compared to traditional concrete. GGBS, LC3, and fly ash offer the most CO2 reductions (in that order).
  • Concrete producers have the incentive to implement LC3, fly ash, GGBS, and portland-limestone cement because they increase plant operating incomes up to 21%.
  • All low carbon mix designs become largely favorable to traditional concrete when considering social costs of carbon and the cost of diverting expensive waste from landfills.
  • This industry may prove difficult to regulate due to the 8,500 US concrete batching plants, antitrust laws, and lack of available data.

The study expands on methodology; LCA results; cost-benefit results; mix design limitations, supply chains, and key takeaways; and policy recommendations. It is accompanied by an ArcGIS StoryMap that provides a quick snapshot of key findings and a Topic Report that expands on the market, green metrics, cost metrics, technologies, policy, company landscape, and researchers (available for purchase at SEP’s marketplace).

The report was developed in a collaborative effort between the UN SDSN and SEP.

The UN Sustainable Development Solutions Network (SDSN) mobilizes scientific and technical expertise from academia, civil society, and the private sector to support practical problem solving for sustainable development at local, national, and global scales. The SDSN has been operating since 2012 under the auspices of the UN Secretary-General. The SDSN is building national and regional networks of knowledge institutions, solution-focused thematic networks, and the SDG Academy, an online university for sustainable development.

Saoradh Enterprise Partners (SEP) is a venture capital and research firm focused on technologies for disruptive sustainability across the nine sectors that comprise the cleantech ecosystem. SEP’s approach is unique, leveraging its innovative market and technology research platform to identify sustainable technology opportunities in emerging cleantech hubs in the US for its investment funds and corporate clients. The SEP team partners with entrepreneurs, innovators such as universities and national labs, and leading corporations to build companies that disrupt valuable segments of supply chains for products that mitigate climate change and other environmental impacts.