The US Department of Energy (DOE) announced a US$1.6bn investment in the cement sector this week. The funding was part of a total of US$6bn for 33 projects in over 20 states to decarbonise energy-intensive industries also including chemicals and refining, iron and steel, aluminium and metals, food and beverages, glass, process heat applications and pulp and paper. The DOE was keen to link the money to “the President’s Bipartisan Infrastructure Law and Inflation Reduction Act.” Politics is never far away it seems! The projects are part of the Industrial Demonstrations Program, managed by DOE’s Office of Clean Energy Demonstrations (OCED).

Table 1: Summary of US Department of Energy funding announced on March 2024 to decarbonise cement and concrete production

Table 1 above shows the main approaches each of the projects aim to use. The two most expensive ones involve carbon capture and sequestration (CCS) at Heidelberg Materials US’ Mitchell cement plant in Indiana and National Cement’s Lebec plant in California respectively. In a complimentary press release Chris Ward, the CEO of Heidelberg Materials North America, said “This substantial federal funding investment will help create the first full-scale deployment of carbon capture and storage on a cement plant in the US.” The proposed CCS unit at the plant will capture around 2Mt/yr of CO₂ from 2030. If Ward’s forecast is accurate (and no one beats them to it), then Heidelberg Materials will likely have set up the first full-scale CCS units at cement plants in both North America and Europe. This will be a significant achievement. The National Cement project, by contrast, is a mixed bag of approaches to decarbonising cement production that follows the multi-lever approach advocated for in many of the industry net-zero roadmaps. It intends to use agricultural by-products such as pistachio shells, as alternatives fuels to lower the fuel-based emissions, calcined clay to lower the clinker factor and CCS to capture the remaining 950,000t/yr of CO₂ emissions.

The other projects either involve using calcined clay or substituting limestone with calcium silicate. The Summit Materials proposal is noteworthy because it aims to build four clay calcination units in locations in Maryland, Georgia and Texas. None of these appear to be near Summit’s (or Cementos Argos’) cement plants. This suggests that the company may be intending to use calcined clay in ready-mixed concrete production. The Roanoke Cement Company calcined clay project will be baseEuropead at its cement plant in Troutville, Virginia.

The remaining two grant recipients, Brimstone and Sublime Systems, will both test the companies’ different methods of manufacturing cement by using calcium silicate instead of limestone. Brimstone’s method produces ordinary Portland cement (OPC) and supplementary cementitious materials (SCM). The company said in July 2023 that its OPC met the ASTM C150 standards. However, the company has released less information about its actual process. Sublime Systems’ uses an electrolysis approach to create its ASTM C1157-compliant cement. It calls this ‘ambient temperature electrochemical calcination.’

Investment on the same scale of the DOE has also been happening in Europe. In July 2023, for example, the European Commission announced an investment of Euro3.6bn in clean tech projects to be funded from the proceeds of the European Union emissions trading scheme (ETS). This was the third call for large-scale projects following previous announcements of recipients in 2021 and 2022. Euro1.6bn of the third call funding went towards cement and refining projects including five cement and lime projects in Belgium, Croatia, Germany and Greece. The money granted for each of these schemes was in the region of Euro115 - 235m.

Both the US and Europe are throwing serious finance at the cement industry to try and kickstart the various pathways towards net zero. They are also doing it in different ways, with the US aiming to boost its economy by onshoring sustainable industry, and Europe hoping to fund its approach via carbon taxation. Government-driven decarbonisation investment for cement in other large countries and regions around the world appears to be lagging behind the US and Europe but these may spring up as net zero targets are set, roadmaps drawn up and government policy formulated. These places could also benefit from watching what works and does not work elsewhere first. Back in the US and Europe the next tricky part of this process will be bridging the gap between government subsidy and commercial viability.