Emission reduction technology sharing with environmental tax under multiple oligopolies

This study constructs a Cournot model with multiple enterprises considering the environmental tax, emission reduction technology research and development (R&D), and technology sharing. First, the solution of R&D and sharing boundaries of emission reduction technology are presented. Next, the effects of technology R&D, technology sharing, and environmental tax rates are analyzed. We also reveal the quantitative boundaries of enterprises participating in technology-sharing. The study finds that enterprise decision-making on emission reduction technology R&D and sharing is affected by factors such as the environmental tax rate, R&D cost, and technology sharing fee. Technology R&D and sharing can increase enterprise profits but reduce consumer surplus. Appropriate environmental tax policies contribute to the improvement of social welfare. Technology R&D helps reduce environmental damage and technology sharing can also achieve this under the influence of various factors such as environmental tax. Environmental tax rates affect consumers, enterprises, and social welfare. Consequently, an optimal tax rate is introduced that maximizes social welfare. Excessive environmental tax rates inevitably damage environmental and social welfare. An optimal number of shared enterprises exist in an enterprise’s competition process.