This paper evaluates the economic impact of Renewable Energy Communities (RECs) on the Italian wholesale power market. Combining a bottom-up engineering approach with a short-run economic impact assessment, the study begins by mapping existing and emerging RECs in Italy. We identify key characteristics of RECs, such as average installed capacity, institutional profiles of members, types of renewable systems used, and transmission across Italy's electricity market zones. This mapping yields representative REC configurations, which are employed within a bottom-up engineering model to generate energy injection and self-consumption profiles for different REC prosumer and producer categories (residential, public, small and medium enterprise, non-profit organization, and standalone installation), considering the different levels of solar irradiance in Italy based on latitude. These zonal results, aggregated on an hourly basis, inform the implementation of the synthetic counterfactual approach, which develops alternative scenarios (e.g., 5 GW target for REC-driven capacity set by Italian policy for 2027) to assess the impact of REC-driven injection and self-consumption on the Italian day-ahead power market. The findings suggest that REC deployment can increase equilibrium quantities during daylight in most of the time, while decreasing equilibrium quantities mostly during the cold months, as electrified heating drives greater self-consumption and offsets lower grid injections. Both positive and negative effects on equilibrium quantities suggest that REC deployment also has a potential to reduce wholesale electricity prices. Moreover, by reducing grid exchanges through higher self-consumption, REC proliferation can alleviate pressure on the distribution system.

翻译：本文评估了可再生能源社区对意大利批发电力市场的经济影响。研究结合自下而上的工程方法与短期经济影响评估，首先对意大利现有及新兴的可再生能源社区进行测绘。我们识别了可再生能源社区的关键特征，包括平均装机容量、成员的机构属性、采用的可再生能源系统类型，以及跨意大利电力市场区域的传输情况。通过测绘得到具有代表性的可再生能源社区配置，将其应用于自下而上的工程模型中，针对不同可再生能源产消者与生产者类别（居民、公共机构、中小企业、非营利组织及独立设施），结合意大利基于纬度的不同太阳辐照度水平，生成能源注入与自消纳曲线。这些按区域统计的结果以小时为单位进行聚合，为实施合成反事实方法提供依据。该方法通过构建替代情景（例如意大利政策为2027年设定的5吉瓦可再生能源社区驱动容量目标），评估可再生能源社区驱动的电力注入与自消纳对意大利日前电力市场的影响。研究结果表明，可再生能源社区的部署在多数时段可提高日间均衡电量，而在寒冷月份则主要降低均衡电量，这是因为电气化供暖导致自消纳增加，从而抵消了电网注入的减少。对均衡电量的正负双向影响均表明，可再生能源社区部署具有降低批发电价的潜力。此外，通过提升自消纳减少电网交互，可再生能源社区的普及能够缓解配电系统压力。