Barcelona has started trialing a new asphalt that replaces limestone filler with biochar made from olive pits and wood waste. The project, backed by the city council and a consortium of companies and researchers, aims to cut CO2 emissions from asphalt production by up to 75 percent. Laboratory tests also show the material is more resistant to moisture, cracking, and temperature changes, which could mean longer lasting roads in urban environments. The pilot will run on real streets for at least a year starting in late 2026. Spain is the world's largest olive oil producer, so the raw material supply is abundant. If the trials succeed, the city could begin deploying the asphalt on full streets by 2027. The approach fits a broader push for circular economy methods in infrastructure, though real world durability under traffic and weather still needs to be proven.
