Carbon-negative concrete pavers used in the parking spaces and footpaths of an Amazon UK delivery station are based on technology developed by Montreal-based CarbiCrete, and could mark the beginning of a larger collaboration.

The project marks the first large-scale deployment of CarbiCrete's pavers, which cover almost 69,000 square feet at the delivery station in Stockton-on-Tees.

The pavers are manufactured without cement, replacing the carbon-intensive binding material with steel slag. The substitution means that for every tonne of concrete produced via CarbiCrete’s process, 150 kilograms of carbon dioxide is averted.

The project with Amazon UK has been “really big for us,” Yuri Mytko, chief marketing officer of CarbiCrete, said in an interview with Sustainable Biz Canada. “It helped us prioritize what products we were going to commercialize first.”

Cutting embodied carbon

Amazon sought out CarbiCrete's pavers as part of its effort to build the 116,250-square-foot delivery station in accordance with the UK Net Zero Carbon Buildings Standard and the Living Future Institute's Zero Carbon Certification.

Amazon UK was “the catalyst for our developing these specific products,” Mytko said, pushing CarbiCrete to prioritize development of the pavers after focusing primarily on masonry blocks.

Manufactured by CarbiCrete's Quebec-based partner Patio Drummond, the pavers came in three varieties: one designed for footpaths and walkways, another for vehicular traffic, and a lattice-shaped grid product.

Installation started in the late spring and finished in the fall, Mytko said. Despite the change in materials, CarbiCrete's pavers are indistinguishable from conventional concrete products. When Mytko visited the facility during construction and talked to the installers about its products, no one was “even aware that there was no cement in the product,” he said. “They handled and installed and cut identically to a cement-based paver.”

Without CarbiCrete's involvement, the parking spaces and footpaths likely would have been paved with conventional concrete pavers or asphalt, Mytko said. Using CarbiCrete's products instead resulted in 33 tonnes of carbon dioxide emissions being avoided.

'Catalysts and leaders' in reducing embodied carbon

Amazon UK’s search for a more sustainable replacement for asphalt is aligned with its goal to reduce embodied carbon.

For the Stockton-on-Tees delivery station, lower-carbon steel and mass timber were used to cut construction emissions by at least 20 per cent compared to the original building design. Complementing CarbiCrete’s contribution, Amazon UK piloted carbon-sequestering concrete and asphalt made by Paebbl Rebond and Low Carbon Materials, respectively.

Following the project with CarbiCrete, Amazon is exploring opportunities to deploy its products on more sites, Mytko said.

The partnership also gives CarbiCrete an opportunity to identify new markets and potential licensing partners. In such a relationship, CarbiCrete offers its technology and expertise to masonry and hardscape manufacturers under license. The manufacturers can then produce concrete products with negative carbon emissions.

While Amazon was a driving force behind the development of the pavers, Mytko said they will not be exclusive to the company. Amazon even insisted that anything made for them has to be usable by others, he added.

“They see themselves as catalysts and leaders in terms of low-embodied carbon construction,” Mytko said. “They made it very clear that they did not want bespoke product; they wanted products that could be used elsewhere."