Renew Sports Cars was a small American specialty-car project associated with Bruce Dietzen, based in Key West, Florida, that emerged in the mid-2010s around a retro-styled roadster commonly nicknamed the “Cannabis Car.” Dietzen built the prototype by rebodying a Mazda Miata-based platform with molded panels made from industrial hemp fibers and plant core (“hurds”) bound in resin, presenting the result as an ultra-low-carbon-footprint sports car…