Environmental Regulations in Private and Mixed Duopolies: Emission Taxes versus Green R&D Subsidies

Abstract

In the presence of R&D spillovers, we compare environmental regulations between an emission taxes and green R&D subsidies in private and mixed duopoly markets. We show that the green R&D subsidy is better (worse) than the emission tax when the green R&D cost is low (high) irrespective of the R&D spillovers, whereas the existence of a public firm encourages the government to adopt the subsidy policy. We then show that the optimal policy choice depends on the level of the R&D cost and the degree of R&D spillovers. In particular, when the R&D cost is high and the spillover rate is (not) weak, the government should choose the emission tax and (not) privatize the public firm. However, when the R&D cost is low, such a privatization policy is not desirable to society irrespective of the R&D spillovers