Rob Niven began to study concrete’s carbon problem as an engineering student at McGill University in Montreal in the early 2000s. Then, the British Columbia native put the ideas he’d developed into action.

Niven formed CarbonCure Technologies, which since 2008 has attracted multiple rounds of venture capital. From its headquarters near Halifax, Nova Scotia, the company has grown a network of nearly 150 concrete plants that use the CarbonCure process to inject carbon dioxide into their concrete mixes and products. The method supplants some of the carbon-intensive cement that usually goes into concrete mixes, sequesters carbon dioxide from other industrial sources, and at the same time strengthens the end-product.

Among other accolades, CarbonCure is one of 10 finalists for the NRG COSIA Carbon XPRIZE, a $20 million competition for ideas that convert CO2 into products. Niven himself has been showered with recognition as one of Canada’s leading technology entrepreneurs.

We took a closer look at CarbonCure after Thomas Concrete’s use of the technology in construction of the Kendeda Building for Innovative Sustainable Buildings. I wrote more extensively about the product itself and its use in the Kendeda Building here.

In the process, however, I had the opportunity to ask Niven via email about CarbonCure’s journey and where he expects the company to go from here. One thing is clear: Niven views his company’s current process — which incrementally reduces embodied carbon in concrete — as just a start; his team is working on methods for more ambitious reductions in the future.

(An editorial note: “Tons” in this this Q&A refer to English tons; “tonnes” refer to metric tonnes, which are about 10 percent larger. Also, questions and answers have been lightly edited for clarity and length.)

Your customer base seems to be growing quite rapidly. What motivates your current customers? In general, what’s driving the market transformation in this very traditional industry?

There are several interconnected things that drive CarbonCure’s customers. While most business leaders want to do the right thing, concrete producers choose to work with CarbonCure mainly because we help them solve their customers’ biggest challenges. Developers and designers are faced with mounting pressure to lower the embodied carbon of buildings. Since we’re on track to double the world’s entire building stock by 2060, we cannot afford to build at the same resource and CO₂ intensity as we are today.

Considering that concrete is by far the most abundant building material, it makes sense that concrete will be the first industry that needs to adapt. By working with CarbonCure, our customers are able to fulfill this demand in the market. We make the transition easy by integrating into existing supply chains, regulatory frameworks and plant production methods without imposing any capital expenditure or new net costs. Frankly, producers that don’t adapt to these market trends will face a competitive disadvantage.

While the potential volume of carbon mitigated by CarbonCure is enormous, it currently reduces concrete’s embodied carbon by only a fraction. Correct me if I’m wrong: Isn’t it about 5 percent? What’s the most viable longterm approach toward reducing concrete-related emissions further?

We are pursuing a 500 megatonne-per-year pathway for CO2 emission reductions. We plan to achieve this figure by:

1. Geographic expansion into new markets beyond [North America].
2. Expanding our portfolio of technologies with other CO2 utilization solutions which beneficially reuse CO2 at a concrete producer site AND contribute to their improved profitability. Current technologies in development can reduce 100kg CO2/ ton of concrete (well beyond the 5 percent). Moreover, they provide circular economy co-benefits of reduced water, waste water, resource use and solid waste.

Our approach of being unrelenting on customer profitability AND CO2 reductions is harder but necessary to scale up to 500 megatonnes There are many other solutions that are being proposed which overstate the CO2 impacts, yet the technology is not commercially viable and/or has fundamental scientific limitations. 

How closely are you following and working with such efforts to measure life-cycle carbon as the Embodied Construction Carbon Calculator tool at University of Washington?

CarbonCure is working very closely with the University of Washington’s Carbon Leadership Forum and is actively involved in the creation of the Embodied Carbon in Construction Calculator (EC3) tool. CarbonCure is a sponsor of the Carbon Leadership Forum and our director of sustainability, Christie Gamble, is a board member. We are very excited for the launch of the tool in the fall of 2019. Our hope is that this tool becomes embedded in the standard construction design practice.

A segment of owners, designers and builders concerned about embodied carbon is moving increasingly toward mass timber. What do you say to them? And might this move toward inherently low-embodied-carbon materials, such as timber, limit demand for concrete in a meaningful way?

CarbonCure works with the concrete and cement industry to reduce the carbon footprint of concrete. We recognize that architects and engineers have the expertise to choose the best building materials for each respective project, and we encourage them to consider the full life-cycle impacts of materials when making these decisions if they are not already doing so.

Comparing building materials in isolation and in one instance of time is not an effective way to evaluate their environmental impacts; rather a life-cycle analysis is needed to truly determine the size of each material’s embodied carbon footprint. Life-cycle analyses show that concrete is actually a low-impact material with a smaller amount of embodied carbon and embodied energy than materials such as timber and steel. (see this graph). Concrete is a significant portion of nearly all buildings and the most widely used material in the world for a reason: It has unrivaled strength, longevity and durability.

We encourage owners and architects to also consider these aspects of concrete when making building material considerations. New tools like Skanska’s new Embodied Carbon Calculator for Construction (EC3) are also making it easier than ever to consider the entire project’s impact and building material selection.

Note: For more research on the sustainable aspects of concrete, I recommend checking out the MIT Concrete Sustainability Hub.

Between ready-mix and concrete products, which is proving to be your busiest market?

CarbonCure is on a pathway to reduce 500 megatonnes of CO₂ annually by helping to lower the embodied carbon footprint of the built environment. To achieve this goal we are developing new clean technologies, serving all concrete segments and entering new global markets. Our roots are in concrete products. However, most of our growth lately has been in ready-mix concrete due to its relatively larger size. In total we are working with nearly 150 producers across Canada, US and Singapore. Stay tuned for news on new markets!

Concrete isn’t just used in buildings. Can CarbonCure can added to concrete applied in other areas, such as infrastructure?

The Hawaii Department of Transportation relied on CarbonCure concrete producer Island Ready-Mix to provide a more sustainable, lower-carbon concrete for the paving of a roadway in Honolulu (the Kapolei Interchange). As you know, all levels of government are struggling to find immediately scalable climate solutions while working within limited budgets. This was a perfect example of how we were able to rapidly support state and city climate targets without impacting budgets.

The HDOT endorsed CarbonCure as an effective way to reduce the carbon footprint of road construction, and had a demonstration pour alongside traditional concrete to determine the specifications for the use of carbonated concrete for future road projects. The successful demonstration saved 1,500 pounds of carbon emissions, which is equivalent to offsetting the emissions from 1,600 miles of highway driving.

This project was special since state and municipal governments and the concrete industry worked together to fast track the adoption of CO₂ mineralization in concrete. Government provided a clear direction for industry by introducing state legislature in Hawaii that would require “all state building construction that uses concrete to use post-industrial carbon dioxide mineralized concrete unless use of these materials will increase costs or delay construction.” In May 2019 the Honolulu City Council also passed a resolution requesting city administration to “consider post-industrial carbon dioxide mineralized concrete for use in all City and County of Honolulu capital improvement projects utilizing concrete where the utilization of carbon dioxide mineralized concrete does not significantly increase the costs of or significantly delay the project.”

Hawaii has created a new scalable model for governments to meet their climate targets without impacting budgets or public safety. We’re already seeing many other governments worldwide adopt the Hawaii model in their own local markets.

To what extent will regulation or incentives encouraging carbon sequestration expand your market? Does the promise (and need) for sequestration play a role in your strategy?

CarbonCure’s business model does not require regulatory changes or incentives. However, the Global CO₂ Initiative estimated that the CO₂ sequestration market for concrete will be an annual $400 billion market opportunity with 1.4 gigaton CO₂ emission reductions by 2030 with the right policies implemented. Organic adoption of carbon sequestration technology in concrete is unlikely to be fast enough to meet the urgent demands of climate change.

In my view, procurement and climate policies must be aligned if we are serious about meeting our targets. We’ve seen private companies and governments like LinkedIn and Hawaii find this balance and protect public interests by ensuring that CO₂ mineralized concrete is preferentially purchased as long as quality and price are not negatively impacted.

PHOTO AT TOP: Rob Niven stands before a CarbonCure tank that stores carbon dioxide at a concrete plant. Photo courtesy of CarbonCure.