Tax or subsidy? An analysis of environmental policies in supply chains with retail competition

This paper investigates the impact of two environmental policies: emissions abatement subsidy and emissions tax, on a three-tier supply chain where the manufacturer distributes through competitive retailers and invests in emissions abatement manufacturing technology. The government pursues social welfare maximization, while the manufacturer and retailers are profit driven. We find that the subsidy policy offers the manufacturer greater incentives to abate pollution and yields higher profits for channel members; however, when emissions abatement is very costly and production emissions are highly damaging, the tax policy should be implemented, as the subsidy policy leads to lower social welfare and environmental performance. Interestingly, we show that the manufacturer has no incentive to improve emissions abatement efficiency if the environmental damage of its production is high under the subsidy policy or low under the tax policy. The manufacturer always welcomes more downstream entry under the subsidy policy but not necessarily under the tax policy; each retailer always fares worse with more competition. More competition enhances social welfare under the tax policy but not necessarily under the subsidy policy. Furthermore, caution should be exercised when adopting the subsidy policy, because a “hazard zone” exists where society suffers but does not under the tax policy.