This study seeks to examine the environmental and societal impacts of a carbon tax in Italy, where the policy has yet to be implemented but has been the subject of much debate. We use numerical simulations based on the EUROGREEN macro-system dynamic model (D’Alessandro et al., 2020) to evaluate the potential benefits and drawbacks of this policy from 2010 to 2050.

We employ a sequential scenario approach, starting with a baseline that incorporates Italy’s Integrated National Energy and Climate Plan (PNIEC), followed by the introduction of a gradually increasing carbon tax. Additionally, we test two hypotheses regarding the possible adaptive behaviors of consumers and producers in response to the policy. Our analysis evaluates the long-term impacts of the carbon tax on GDP, unemployment, public debt, carbon emissions, and income inequality, in pursuit of a ”quadruple-dividend” effect.

Our findings suggest that the carbon tax: ($i$) has a limited impact on reducing carbon emissions, with a difference of only 2% compared to the PNIEC by 2050, ($ii$) has the potential to mitigate regressive effects through the redistribution of its revenue to low-income households, resulting in an improvement of approximately 2 Gini-points compared to the PNIEC, and ($iii$) can achieve a quadruple-dividend effect only if consumers and industries adapt their behavior to the policy.

Our research argues that Italy could reap the benefits of a carbon tax, with the revenue being redistributed to low-income households, leading to a more equitable and sustainable energy transition. This can only be achieved by combining top-down policies with bottom-up initiatives and public interventions, making environmental taxation more acceptable to the general public.

这项研究旨在研究意大利碳税的环境和社会影响，该政策尚未实施，但一直是争论的主题。我们使用基于 EUROGREEN 宏观系统动态模型（D'Alessandro 等人，2020 年）的数值模拟来评估该政策从 2010 年到 2050 年的潜在利弊。

我们采用顺序情景方法，从包含意大利综合国家能源和气候计划 (PNIEC) 的基准开始，然后引入逐渐增加的碳税。此外，我们检验了关于消费者和生产者响应政策可能的适应性行为的两个假设。我们的分析评估了碳税对 GDP、失业、公共债务、碳排放和收入不平等的长期影响，以追求“四倍红利”效应。

我们的研究结果表明，碳税：($我$)对减少碳排放的影响有限，到2050年与PNIEC相比仅相差2%，($我我$) 有可能通过将其收入重新分配给低收入家庭来减轻倒退效应，从而与 PNIEC 相比提高约 2 个基尼点数，并且 ($我我我$) 只有消费者和行业调整他们的行为以适应政策，才能实现四倍红利的效果。

我们的研究认为，意大利可以从征收碳税中获益，将收入重新分配给低收入家庭，从而实现更加公平和可持续的能源转型。这只能通过将自上而下的政策与自下而上的举措和公共干预相结合，使环境税更容易为公众接受来实现。