This paper analyzes the effect of environmental policies on the direction of energy innovation across
countries over the period 1990-2012. Our novelty is to use threshold regression models to allow for
discontinuities in policy effectiveness depending on a country's relative competencies in renewable and
fossil fuel technologies. We show that the dynamic incentives of environmental policies become effective
just above the median level of relative competencies. In this critical second regime, market-based policies
are moderately effective in promoting renewable innovation, while commandand-control policies depress
fossil based innovation. Finally, market-based policies are more effective to consolidate a green
comparative advantage in the last regime. We illustrate how our approach can be used for policy design in
laggard countries