On the interactive effects of climate policies: Insights from a stock-flow consistent model

Climate policies such as carbon tax and green finance policy are critical measures to promote low-carbon transition worldwide. These policies are, however, likely to interact with each other and create unintentional consequences. This paper adopts a stock-flow consistent model to theoretically explore the effects of policy interactions. Specifically, commercial banks, as the key credit creators and critical players in providing source of finance, are included. Based on the numerical simulations of the dynamic model, we find that both carbon tax and green finance policies render positive impacts on low-carbon transition. In addition, green credit incentives, if imposed simultaneously with carbon tax, can enhance the positive effects. Although low-carbon transition could generate higher net government revenues, our results show that banking sector tends to expose to higher financial risks when firms’ debt-equity ratio rises. Further analysis shows that subsidies on green loans can support green transition and bring positive consequences to debt rollover and social welfare, indicating the needs for active government intervention to improve policy effectiveness. The framework proposed in this paper provides a useful way to understand policy dilemmas in pursuing low-carbon transition and give important implications to form optimal policy mix.