CarbonBuilt, a rapidly growing low-carbon concrete startup, announced on Wednesday that it has begun commercial production of its climate-friendly concrete, together with concrete masonry production partner Blair Block. The companies also have their first commercial customer lined up, marking a major step forward for the three-year-old startup.

Concrete is the most widely used construction material in the world, but efforts to decarbonize its production have been limited in scope until recently. Existing solutions range from either expensive carbon-negative technologies that are far from commercialization to lower-cost, readily available alternatives that deliver limited emissions reductions.

But CarbonBuilt claims its technology — which won the NRG COSIA Carbon XPRIZE in 2021 — is capable of reducing the amount of carbon dioxide emitted during the lifecycle of concrete by 70% to 100%, while costing the same to produce as traditional concrete.