Environmental policies and productivity growth: Evidence across industries and firms

This paper investigates the impact of changes in environmental policy stringency on industry- and firm-level productivity growth in a panel of OECD countries. To test the strong version of the Porter Hypothesis (PH), we extend a neo-Schumpeterian productivity model to allow for effects of environmental policies. We use a new environmental policy stringency (EPS) index and let the effect of countries׳ environmental policies vary with the pollution intensity of the industry and with the countries' and firms' technological advancement. A tightening of environmental policy is associated with a short-term increase in industry-level productivity growth in the most technologically-advanced countries. This effect diminishes with the distance to the global productivity frontier, eventually becoming insignificant. For the average firm, no evidence of PH is found. However, the most productive firms see a temporary boost in productivity growth, while the less productive ones experience a productivity slowdown.