In recent times, there has been a significant shift from centralized energy systems to decentralized ones. These systems aim to satisfy local energy needs using renewable resources within the community. This approach leads to decreased complexity and costs, improved efficiency, and enhanced local resilience and supports energy independence, thereby advancing the transition toward zero carbon emissions. Community energy plays a pivotal role globally, particularly in European countries, driven by citizen engagement in generating power from renewable sources. The European Union, known for its focus on social innovation and citizen participation, recognizes the essential role of energy communities in its latest energy strategy. The concept for creating local energy communities or community-based energy projects has gained worldwide attention, demonstrating the economic, environmental, and efficiency benefits for using renewable energy sources. However, there is a noticeable gap in research covering all the updated aspects of renewable energy communities. This article provides an in-depth review of energy communities, especially renewable energy communities, exploring their concepts, scope, benefits, and key activities. It also sheds light on their progress by presenting results and analyses. Some countries have shown significant advancement, others are in the initial stages, and a few have partially adopted REC implementation according to the Renewable Energy Directive II. Additionally, it discusses the main challenges and potential recommendations to enhance the growth of renewable energy communities. This work is a valuable resource, emphasizing the importance of citizen involvement and offering insights into various aspects of community energy for sustainable energy transition. It also provides practical insights and valuable information for policymakers, researchers, industry professionals, and community members who are keen on promoting sustainable, community-driven energy systems.

The Renewable Energy Community (REC) in Europe promotes renewable energy sources (RESs), offering social, economic, and environmental benefits. This new entity could alter consumer energy relationships, requiring self-consumption, energy sharing, and full utilization of RESs. Modernizing energy systems within the REC requires addressing self-consumption, energy sharing, demand response, and energy management system initiatives. The paper discusses the role of decentralized energy systems, the scenarios of the REC concept and key aspects, and activities involving energy generation, energy consumption, energy storage systems, energy sharing, and EV technologies. Moreover, the present work highlights the research gap in the existing literature and the necessity of addressing the technological elements. It also highlights that there is no uniform architecture or model for the REC, like in the case of microgrids. Additionally, the present work emphasizes the role and importance of technological elements in RECs, suggesting future recommendations for EMS, DSM, data monitoring and analytics, communication systems, and the software or tools to ensure reliability, efficiency, economic, and environmental measures. The authors also highlight the crucial role of policymakers and relevant policies, which could help in implementing these technological elements and show the importance of the RECs for a sustainable energy shift and transition.

In recent years, the production of renewable energy has increased continuously to reduce fossil fuel consumption and CO₂ emissions and to increase energy efficiency. The challenge of industries is to integrate renewable energy systems into the existing power system of manufacturing industries. In the energy flexibility approach, the manufacturing energy demand is aligned with renewable energy availability, to improve the use of the renewable energy source. This paper aims to investigate a manufacturing system supplied by a photovoltaic plant coupled with a battery storage system. A basic storage model has been developed and implemented to pursue this issue. The model is applied in the simplified case of a manufacturing system composed of a cutting numerical control machine, which can adapt the cutting speed to align the power needed to the power supplied by the photovoltaic plant. However, the model can be extended to realistic production cases characterized by complex systems as long as the time evolution of energy consumptions are known in detail. The introduction of battery storage allows reducing the cutting speed fluctuations, improving the cutting life derived from the fatigue effect. This solution reduces the costs of the machine and improves the forecasting of the means needed for the manufacturing system. Finally, a detailed analysis of greenhouse gas reduction is discussed.