If the built environment is the grocery store, then in a world full of climate change worries, “embodied carbon” is the nutrition label.
Carbon dioxide is the salt, sugar and fat on the label.
Manufacturing road asphalt, concrete, reinforcing steel and bricks creates large amounts of the greenhouse gas. Now a pioneering Colorado law will require the building trades to slap labels on everything they produce, detailing how much carbon was “embodied” in the making.
And in the future, major material buyers, including the Colorado Department of Transportation or the state architect, must start comparing those carbon nutrition labels when buying for road building and other big projects. Conservation groups and industry leaders say Colorado joined California at the front of the embodied carbon movement when it passed House Bill 1303 this year, and many more states will now follow.
Backers of the law say the labels, or “environmental product declarations,” will be another key factor in cutting greenhouse gas emissions in Colorado and worldwide. The clean energy think tank RMI says building emissions make up at least 39% of the global greenhouse total, and that the carbon created in producing the materials for those buildings is at least 25% of that.
The high figure makes road tar, cement and bricks a big target for the next wave of regulation.
Cement-making worldwide produces as much greenhouse gas as the third-largest emitting nation in the world, said Colorado Rep. Tracey Bernett, a Longmont Democrat and one of the sponsors of the embodied carbon bill. “We have an opportunity to really make a difference in terms of reducing greenhouse gas emissions, and leading the nation and the world.”
RMI’s research claims manufacturers could cut the carbon input of many of the most commonly used building materials by 24% to 46% without raising prices by more than 1%. Cement kilns could use more renewable energy, sequester carbon, or even lower the portion of cement in concrete; petroleum producers could cut emissions in drilling and refining asphalt products.
The manufacturers say they are on board with the law and are preparing the benchmark studies required in the early phases of the law. They add that they’ve already made important strides reforming how they make materials to sharply cut greenhouse emissions.
Building materials already greener?
By sheer volume, asphalt is the biggest recycled product in the United States, said Tom Peterson, executive director of the Colorado Asphalt Pavement Association.
“I’ve grown up in the industry literally since I was a little kid, and the plants, the production facilities, of a generation ago are not what they are today,” Peterson said. “Our industry is proud of the fact that over the last 30 years production has gone up 250% At the same time, emissions have dropped 97%.”
Bill supporters give similar credit to Colorado industrial leaders, and said that should help the state in future years when it has to start seeking materials with the best carbon scores. The Evraz steel plant in Pueblo, for example, uses recycled steel as its base production material, and the high energy needs of the plant are increasingly met by enormous solar farms cropping up around the site.
The large cement-making plant in Florence that makes the binder for concrete, LafargeHolcim, is also considered a leader in carbon capture technology for the energy-intense process of baking cement in kilns. Carbon dioxide produced by the kilns can be sold to the oil and gas industry, which injects it underground to boost field production, or sequestered underground to keep it from the atmosphere.
State highway officials said they are not only ready to begin asking bidders for their benchmark carbon scores in July 2022, as the bill required — they may start sooner.
“We’re trying to beat that out of the blocks, and at least get some projects out this winter so we can expose ourselves and the contractors to the information that we want to look for,” said Craig Wieden, CDOT’s materials and geotechnical branch manager.
The faster time frame may have been news to the asphalt association, where members often prefer technical consultation with CDOT over broad policymaking in the legislature.
“One of the reasons for being deliberate in your time frame is to ensure that you’re collaborating with the affected industry,” Peterson said. Still, he added, the asphalt makers are glad the new law set up the first few years as data collecting and benchmarking before CDOT has to start making policy choices on how it purchases carbon-based goods.
Benchmarking becomes policy in 2025
The law charges CDOT with setting benchmarks for now, and then with creating policies to lower the carbon footprint of the purchased goods as much as possible, starting in 2025.
Where the comparison to groceries may fall apart is by geology and geography. Certainly in the asphalt industry, fossil fuels are a base element in the making and have not been replaced by workable alternatives. (Asphalt is a semi-solid form of petroleum.)
Moreover, highway contractors often build makeshift production plants right where they are working. Conservation groups, regulators and industry are still working out which carbon is considered in the material scores: Only the carbon used for a finished product? Or do you add in the carbon it takes to transport the goods and put it in place at a construction site?
The answers will also affect the difference in carbon scoring and price between purely local materials and those transported over great distance from other states.
“That’s the million-dollar question at this point,” Wieden said.
Bernett said Colorado supporters of the bill are fielding calls from multiple states, conservation groups and regulators. Seven states introduced proposals to track or cut embodied carbon in 2021, according to Meghan Lewis, a researcher at the University of Washington and part of the Carbon Leadership Forum. Colorado’s was the second to pass, after California, Lewis said, “with Colorado’s having a more comprehensive materials list.”
The time set aside for data gathering and benchmarking, Bernett said, also gives supporters the chance to bolster their claims that Colorado can improve the way it builds big things while modernizing industry and creating new green jobs in the most advanced companies.
“We can make huge progress without any increase in cost to Colorado,” Bernett said. “It’s just changing the way we’re thinking.”