Environmental Performance Assessment of Concrete Mix Designs for Sustainable Concrete Production in Panama

The environmental performance of concrete depends on both production processes and mix design efficiency. This study evaluates the environmental performance of 74 local concrete mix designs and a concrete production plant using key environmental performance indicators proposed for Panama, based on a previous consultation with the local industry. The CO2 equivalent intensity of the mix designs, which accounts for compressive strength, ranged from 7.37 to 18.10 kg CO2eq m−3/MPa, with substantial variability among designs of comparable strength. Only 22% of the designs incorporated local alternative raw materials, mainly natural pozzolan or fly ash, which contrasts with international trends; natural pozzolan shows the greatest potential, as the availability of local fly ash is currently limited. At the plant level, direct emissions from diesel use ranged from 9.94 to 19.04 kg CO2eq/m3, while electricity consumption exceeded the reference considered and water consumption exceeded it in the months of highest demand; both were higher during the rainy season. Optimizing the mix designs to reduce their binder content is a priority, followed by reducing diesel consumption, while increasing the use of natural pozzolan and improving water and electricity efficiency require further investigation. The proposed indicators provide a practical screening tool, rather than a complete life cycle assessment, for comparing concrete formulations and monitoring plant performance.