Concrete ways to decarbonize building materials

We can optimize policy design for jobs and the climate equitably

Carbon180
6 min readAug 19, 2021

by Mohammed Gueye, Carbon180 intern

As a Carbon180 intern and recent architecture graduate, I see a crucial window of opportunity for climate policy and the building materials industry. Manufacturing building materials — including the brick, concrete, and steel that surrounds us — requires extremely emissions intensive processes with complex, decentralized supply chains. With a few important steps, we can drastically reduce emissions associated with building materials while supporting workers in a transitioning economy. The release of the American Jobs Plan and the lasting socioeconomic consequences of the pandemic enforce the importance of near-term action.

Cement and concrete are particularly urgent when it comes to decarbonizing building materials. The cement industry as a whole generates about 8% of total global emissions. At the same time, the cement and concrete products sector of the US workforce was hit especially hard by the pandemic, losing 15,900 jobs from March to April 2020. Only about a fifth have returned.

There’s no doubt that low-carbon concrete and carbon-sequestering concrete products are necessary for a carbon-neutral society. Sequestering carbon in concrete itself — a charge led by companies like CarbonCure and Solidia — makes critical headway, but we must also consider how decarbonization policies and technologies impact jobs and people.

To meet the moment, we need decarbonization policies that both:

  • spur demand for low-carbon concrete and
  • analyze existing employment structures to safely transition concrete and cement plants to carbon-sequestering practices.

Reducing and removing emissions across a massive supply chain

Concrete is the most commonly used building material on the planet. Cement is the binding ingredient in concrete, created with raw materials that are blended and fired to create “clinker,” which is sold as “portland cement.” The US currently has 96 cement plants that create and grind clinker.

A staggering 90% of emissions along the concrete supply chain stem from the production of cement, but plants could cut those emissions in three key ways. Swapping out cement for lower-emissions alternatives in concrete recipes is one pathway (leading to a possible emissions reduction of 37%). Carbon capture and storage technologies can also sequester process and combustion emissions from cement production (an emissions reduction of 48%).

Lastly, other concrete inputs and products have the capacity to store carbon. Captured atmospheric CO2 can be used to mineralize aggregates before they’re introduced into the concrete mix and cure concrete products, sequestering the carbon within the concrete. The emissions benefits of these carbon utilization approaches is situationally dependent, but in combination with the above tactics, could make concrete production carbon negative.

Managing labor implications while decarbonizing

With emissions reduction efforts, we can expect to see parts of the concrete and cement supply chain shrink or grow because of changing supply, demand, and upfront costs for new carbon curing technology. Those changes will have workforce implications.

Nationally, the cement industry employs about 14,000 people. But the number of employees in each part of the industry varies. For example, there are slightly more workers producing ready-mix concrete (the material transported in the rotating cylinders you see on trucks) than other concrete products, such as cinder blocks or pavers. Consumption also differs. Demand for ready-mix concrete is significantly larger than other concrete products — a ratio of 7:1. As each part of the sector takes on decarbonizing efforts, we must carefully consider these ratios so as not to disrupt the supply chain or the workforce itself.

The upfront cost of implementing new technologies such as carbon curing chambers may, at first, be prohibitive for plants with a disproportionately high number of employees compared to the volume of cement sold. In other words, the sectors with the highest employment may be least financially equipped to decarbonize.

Policy changes for a more sustainable and equitable future

In order for policymakers to support labor, we need to design emissions standards and programs that are informed by workforce trends. Policy should reduce emissions but also improve workplace conditions and support a just transition. Because companies in some sectors employ more individuals relative to the cement they consume, new changes and technologies may have unforeseen impacts down the line if such programs are not piloted and closely monitored.

For example, the New York State Assembly recently passed the Low Embodied Carbon Concrete Leadership Act (LECCLA), which establishes an emissions-based procurement method for concrete. LECCLA initiates the complicated task of designing standards that will guide how the state accounts for carbon emissions in its concrete purchasing decisions.

As the sector reduces cement consumption with alternative materials, facilities downstream and their employees may be most affected. In New York, two integrated cement plants sell to manufacturers of ready-mix producers and concrete products including pipes, blocks, and bricks. These smaller establishments produce negligible emissions compared to cement plants, but they could be subject to price hikes of cement during decarbonization. Likewise, changes to the employment and supply chain structure of cement plants will have implications for distribution and manufacturing companies, which employed 4,456 people in March 2020 compared to 462 in the cement sector at large. In addition to these plants, New York sources half of its cement from out of state, so LECCLA may have unforeseen impacts on employment and interstate commerce in the coming years.

None of this should hinder an ambitious effort to decarbonize the sector, but a labor-conscious policy design will be necessary to maintain the economic value of the supply chain. By the numbers, we know that ready-mix concrete purchases make up a majority of cement sales nationally but a little over half of the sector’s employees, which suggests that there are opportunities to employ more people while using less cement (and therefore less carbon) as we decarbonize concrete and cement products.

Two federal policy changes can help ensure a more sustainable and equitable transition across the country:

1. Require Environmental Product Declarations (EPDs) for all cement and concrete products purchased by the US government

EPDs assess the environmental impact of a product’s life cycle. Directing the Department of Energy (DOE) to establish EPDs for all cement and concrete products purchased by the US government will help policymakers assess the environmental impact of different facilities and products and serve as a baseline for future regulations and incentives. In coordination with the Environmental Protection Agency (EPA) and the Government Services Administration (GSA), DOE should develop a standardized and streamlined framework for cement and concrete products. If required for government contract bids, a uniform EPD tool would provide more transparency to consumers, researchers, and companies. The data would offer insight into whether certain facilities or products are at risk of being uncompetitive for government contracts due to high prices, leading to potential declines in employment.

2. Establish regional pilot programs to assess employment and economic viability of policies related to the decarbonization of building materials

DOE recently pledged $99 million toward large-scale pilot projects that test the feasibility, design, and performance of carbon capture. The department should work with the Bureau of Labor Statistics to develop similar pilot programs that evaluate how emissions standards, procurement, and incentive programs might impact the workforce and economic viability of a region’s facilities. Comprehensive data on the supply chain distribution of employees is currently unavailable. Such insights will be vital to preventing job loss within the concrete and cement products sector as it’s decarbonized.

To get in touch with our policy team, shoot us a note at policy@carbon180.org.

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