Carlo Alberto Nucci

Urban areas account for over 70% of greenhouse gas emissions and are therefore central to the European Union’s goal of climate neutrality by 2030. This paper examines energy communities as enabling mechanisms for the urban energy transition, focusing on their capacity to integrate renewable generation, strengthen local engagement, and improve system-level performance. Framed within the EU’s Climate Neutral and Smart Cities Mission, energy communities are interpreted through the lenses of connectivity, circularity, and the regenerative economy, as they link prosumers through digitally coordinated, decentralized energy exchanges that promote local energy reuse and value regeneration. While not a standalone solution, energy communities illustrate a systemic approach that complements broader electrification, smart grid, and governance strategies. Specifically, we present a day-ahead scheduling model applied to a real medium-voltage distribution network in Modena, Italy. This model minimizes energy procurement costs, derives internal transaction prices using shadow prices, and shows how storage and local generation enhance economic and operational performance. We also quantify how community size and energy exchange rules affect efficiency. The results show that energy communities – when embedded in broader electrification and smart grid strategies – can play a catalytic role in building resilient, interconnected, and regenerative urban energy systems.

The paper proposes the implementation of a controlled DC microgrid to supply DC loads in a plating industry. The plating loads, typically from chromium-based surface coating processes, are characterized by low voltage (10-20 V) and high currents (5-10 kA). To adopt renewable sources, the supplying 600 V-DC microgrid is powered by a photovoltaic (PV) system and a Battery Energy Storage (BES) system. Main aim of the work is to develop a smart strategy to reduce energy consumption, while lowering electricity costs, and minimizing the current ripple affecting the loads. Since PV systems cannot provide a continuous power supply, the system also includes an interface with the external AC grid by a bidirectional DC/AC converter. This hybrid converter allows to feed back the PV energy excess to the grid, still ensuring electricity supply when needed. The paper wants to provide a technical-economic overview, from the sizing of PV and BES systems to the voltage control system, including an Energy Management System (EMS). In particular, the study is aimed at determining the optimal PV system size and BES capacity size to maximize the Net Present Value (NPV) of investments-originated savings. Industrial electricity load profiles, PV generation data derived from 18 years of average hourly irradiation, and three years of electricity price profiles are adopted as optimization inputs. Particularly, the BES power is optimized over a one-year period to minimize grid energy exchange, with annual cost curves to maximize the NPV. Finally, with the same MILP approach as sizing, an EMS with real-time control is proposed in the optimization of microgrid devices, while the DC voltage control system is discussed in detail with tests performed on a Hardware In the Loop (HIL) platform in some scenarios among equilibrium conditions. The paper aims to make a contribution to the development of energy management strategies for reducing procurement costs in industries that make extensive use of DC current, suggesting the entire process, from the optimal calculation of the sizing of the components, to the daily management of the microgrid with optimized scheduling of the EMS, including the control system.

The increasing penetration of renewable energy introduces significant challenges to grid stability and economic performance due to the intermittent and non-dispatchable nature of solar and wind generation. These fluctuations contribute to grid congestion, frequency control issues, and price volatility, reducing revenue predictability for renewable producers. It is then clear that the challenge of energy transition can be addressed by making the introduction of renewable sources into the electricity grid sustainable. Battery Energy Storage Systems (BESSs) have emerged as a flexibility resource providing time-shifting, frequency and voltage support, congestion management, and energy arbitrage. In response, several Transmission System Operators (TSOs), such as Terna in Italy in cooperation with photovoltaic (PV) and wind power producers, have initiated flexibility projects. However, these projects are limited and should be accompanied by liberalization measures that allow BESSs to be economically sustainable only under market conditions. This study evaluates the techno-economic feasibility of utility-scale BESSs either integrated into large PV/wind farms or stand-alone for providing grid flexibility services and profit increase for the producers. Both market conditions and TSO incentives will be considered. A two-step mixed integer linear (MILP) optimization approach is employed: first, an optimization schedules BESS charge and discharge operations based on historical generation and market data; second, the Net Present Value (NPV) is maximized to determine optimal system sizing and profit. The model is validated through real case studies and sensitivity analyses including BESS degradation, market volatility, and regulatory factors. The developed model is ultimately applied to compare the study cases, and the analysis shows that, under specific conditions, the arbitrage of a stand-alone BESS can be as profitable as the incentives offered by TSOs.

Rrenewable energy is crucial for achieving carbon neutrality, particularly in cities, which play a pivotal role in energy consumption and greenhouse gas (GHG) emissions. Europe’s Mission Climate Neutral and Smart Cities initiative targets 100 cities to achieve climate neutrality by 2030, setting a model for broader adoption by 2050. Key strategies include improving energy efficiency, deploying renewable energy sources and energy storage systems, and electrifying end-use sectors, while also considering the diversification of primary energy sources and technologies. This article emphasizes the potential of energy communities within the evolving European directive framework. These communities enable electricity consumers, producers, and prosumers to exchange energy directly, fostering collaboration and local renewable generation. National adaptations of this framework vary due to differences in legislative and regulatory traditions. Social considerations, particularly user engagement in managing benefits and participating in local energy markets, are briefly discussed, along with privacy issues.

The contribution discusses the goal of achieving global climate neutrality, focusing on the activities of cities, energy production, and consumption. Europe is committed to supporting a hundred selected cities in reaching climate neutrality by 2030 through the Mission Climate Neutral and Smart Cities. This commitment combines climate neutrality with the concept of smart cities, promoting innovation and setting an example for other cities to achieve climate neutrality by 2050. For the hundred cities, Europe envisions the use of financial tools, regulatory interventions, and a Climate City Contract, along with funds from the national recovery and resilience plans, which are expected to be suitably coordinated. Due to the continued high consumption of fossil fuels, and of their inevitable use in the coming – hopefully few - decades, efforts must be made to improve the efficiency of existing power plants and utilize less polluting fossil fuel sources. The use of renewable sources, particularly solar, wind, and hydroelectric power, becomes increasingly imperative. Gradual electrification of sectors emerges as a key strategy for the energy transition, considering the natural integration of these sources into the power grid. The use of hydrogen as an energy carrier and storage source, as well as ongoing research in nuclear energy, are additional essential elements contributing to the implementation of a diversified energy strategy deemed necessary. The widespread adoption of information and communication technologies (ICT) and smart sector integration are also fundamental components of the energy transition. Renewable energy communities of prosumers, promoted by the European directives RED II and IEM of the Clean Energy Package, could potentially generate 20% of the energy consumed in cities by 2030, further emphasizing the importance of the electrical system and smart grids in this context.

Renewable energy has a crucial role in facing climate change. One promising strategy is the creation of energy communities that require active involvement from a bottom-up perspective. Their implementation is difficult, as they currently rely on local policies, community readiness, and technological availability. The objective of this paper is to provide a qualitative overview of energy community concepts and strategies at the European level. The aim is to identify common approaches that are framing the development of energy communities, and to understand the most successful steps leading to their creation and growth. To achieve this objective, a threefold methodology is provided: (1) an updated review on policies dealing with energy communities at the European and Italian level; (2) a qualitative overview of European-funded projects under the Horizon 2020 work program; and (3) a qualitative overview of some of the most successful existing energy communities in Europe. The results outline a series of considerations and lessons learned that are useful for implementing this transition pathway in a real case, which is also presented in the paper. The conclusions will identify some future directions of this research, particularly in relation to the results coming from the implementation of actions in the real case.

The state estimation of distribution networks has long been considered a challenging task for the reduced availability of real-time measures with respect to the transmission network case. This issue is expected to be improved by the deployment of modern smart meters that can be polled at relatively short time intervals. On the other hand, the management of the information coming from many heterogeneous meters still poses major issues. If low-voltage distribution systems are of interest, a three-phase formulation should be employed for the state estimation due to the typical load imbalance. Moreover, smart meter data may not be perfectly synchronized. This paper presents the implementation of a three-phase state estimation algorithm of a real portion of a low-voltage distribution network with distributed generation equipped with smart meters. The paper compares the typical state estimation algorithm that implements the weighted least squares method with an algorithm based on an iterated Kalman filter. The influence of nonsynchronicity of measurements and of delays in communication and processing is analyzed for both approaches.