The paper focuses on the day-ahead operational planning of a grid-connected local energy community (LEC) consisting of an internal low-voltage network and several prosumers including generation units, battery storage systems, and local loads. In order to preserve, as much as possible, the confidentiality of the features of prosumers' equipment and the production and load forecasts, the problem is addressed by designing a specific distributed procedure based on the alternating direction method of multipliers (ADMM). The distributed procedure calculates the scheduling of the available energy resources to limit the balancing action of the external grid and allocates the internal network losses to the various power transactions. Results obtained for various case studies are compared with those obtained by a centralized optimization approach. The results confirm that, in the considered LEC framework, each of the prosumers achieves a reduction in costs or increases revenues in case it participates to the LEC with respect to the case in which it can only transact with an external energy provider.

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.

This paper deals with a DC microgrid powered by a photovoltaic (PV) system, supported by a Battery Energy Storage System (BESS) to supply DC loads of specific industrial processes and tertiary applications. These microgrids are of interest for industries characterized by high energy consumption (energy-intensive). The relevant objective is to reduce energy import from the grid, lower energy procurement costs, and minimize current ripple affecting the DC loads. The system includes an interface with the AC grid through a bidirectional DC/AC converter in order to export surplus of PV energy to the grid and guarantee electricity supply when needed. It also integrates a charge controller to manage the BESS system using a dedicated energy management system (EMS). This study focuses on determining the optimal BESS capacity 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 used for the optimization inputs. BESS power is optimized over a one-year period to minimize grid energy exchange, with annual cost curves used to maximize the NPV. In addition, an optimization algorithm implemented in the EMS useful for the daily scheduling of the system is also proposed.

This study deals with the implementation of a DC microgrid powered by a photovoltaic (PV) system and a Battery Energy Storage (BES) system to supply DC loads in a plating industry. These loads, typically from chromium-based surface coating processes, are characterized by low voltage (10 – 20 ~ V) and high currents ($5-10 \text{kA}$). The objective of the study is to reduce energy consumption, lower electricity costs, and minimize current ripple affecting the loads. Since PV systems cannot provide a continuous energy supply, the system includes an interface with the AC grid through a bidirectional $\text{DC} / \text{AC}$ converter. This hybrid converter allows feeding excess PV energy back to the grid, still guaranteeing electricity supply when needed. The study focuses on 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 used for the optimization inputs. BES power is optimized over a one-year period to minimize grid energy exchange, with annual cost curves to maximize the NPV.

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.

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.