Peer-to-peer sharing has become increasingly popular in recent years. Many digital platforms exist that allow individuals to use others’ belongings part-time. These platforms explicitly mention their green credentials, as the environmental benefits of such sharing initiatives are often taken for granted. However, there is a recent empirical literature showing evidence of the contrary. We propose a theoretical framework to analyze the economic and environmental implications of peer-to-peer sharing. We present a stylized model where a monopolist supplies a product that is suitable for rent on a sharing platform. Interestingly, we find that the existence of such a platform is typically beneficial for the monopolist, especially in the long run, when she can optimally anticipate the effects of her decisions on the sharing market. Such a scenario may not be beneficial for consumers, especially for those who rent the good rather than buy it. Moreover, the existence of the sharing platform induces higher use and (under some likely conditions) larger production levels and shorter product lifespans. The combination of these three aspects contributes to a worse environmental impact with sharing, which provides a theoretical rationale for the aforementioned empirical studies.

中文翻译：

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点对点共享的战略定价、寿命选择和环境影响

近年来，点对点共享变得越来越流行。许多数字平台允许个人兼职使用他人的物品。这些平台明确提及其绿色资质，因为此类共享举措的环境效益通常被认为是理所当然的。然而，最近的实证文献显示了相反的证据。我们提出了一个理论框架来分析点对点共享的经济和环境影响。我们提出了一个程式化的模型，其中垄断者提供适合在共享平台上出租的产品。有趣的是，我们发现这样一个平台的存在通常对垄断者有利，特别是从长远来看，当她可以最佳地预测其决策对共享市场的影响时。这种情况可能对消费者不利，特别是对那些租用商品而不是购买商品的人来说。此外，共享平台的存在会导致更高的使用率和（在某些可能的条件下）更高的生产水平和更短的产品寿命。这三个方面的结合导致了共享对环境的影响更加严重，这为上述实证研究提供了理论依据。