This paper introduces endogenous and directed technical change in a growth model with environmental constraints. A unique final good is produced by combining inputs from two sectors. One of these sectors uses "dirty" machines and thus creates environmental degradation. Research can be directed...

Can directed technical change be used to combat climate change? We construct new firm-level panel data on auto industry innovation distinguishing between “dirty” (internal combustion engine) and “clean” (e.g. electric and hybrid) patents across 80 countries over several decades. We show...