The Clean Energy package recognizes and offers a favorable regulatory framework for citizens and energy communities with renewable energy sources. However, various countries’ national regulations will be highly important for the successful development of energy communities in existing cities and surrounding areas. Energy communities represent a way in which citizens and local authorities can invest in clean energy sources and energy efficiency, with several benefits in addition to the financial ones, like strengthening the concept of community and individual contributions to reductions in the overall carbon footprint. In this paper, an overview of recent developments in financial incentives in energy communities, their organization, and typologies, as well as benefits shared among the participants, is performed. The overview reveals the potential of energy communities in contributing to the economic, energetic, and social development of cities towards sustainable and smart cities.

To accommodate the intermittent renewable energy sources in existing power systems, the expansion of networks, storage integration, back-up capacities and efforts for a flexible consumption are required, otherwise grid can be overloaded. The transmission expansion planning (TEP) has the purpose to ensure two important objectives: economic trade and engineering reliability. TEP can increase the competitiveness of the market participants, providing the reliability and safety of the power grid. In this paper, TEP problem is formulated for establishing the optimal decisions in a large real network with classical generators and high share of RES to minimize load-shedding costs and to facilitate energy exchange between consumers and producers. The analysis results were obtained considering the variation of investment budget for a certain number of new transmission lines.