## 2 Research Topics Represented in This Special Issue
### Plants Based on Photovoltaic (PV) Panels and Battery Energy Storages  
[PERSON] and [PERSON] [3] proposed a solution to eliminate the adverse effects of uncontrolled electric vehicle charging, for hybrid electric vehicle charging stations coupled with the small-scale PV fields and battery energy storages. Their method, allowing one to perform a detailed calculation of renewable energy share coming from energy stored in the battery, is based on a multicriterion optimization of the charging/discharging schedule of the battery and electric vehicle charging level. They aim at reducing the charging costs and battery degradation, and at maximizing the solar renewable energy source. Adapting their method for a suitable case study, the results show that in the case of maximizing only the electric vehicle charging energy originating from renewable sources, the solar plant produces 86.7% of the required energy. [PERSON] et al. [4] developed a mathematical model to find the optimal portfolio for an energy community, considering the energy demand and the local source availability. The solution of the optimization problem, the Shapley value, was used, as a known method able to allocate costs and profits of shared infrastructures as well as to distribute benefits among community members. The model was applied to a real case study, related to the low-voltage grid of Chiou, part of the village of Porossan in the municipality of Aosta. The resulting optimal energy community configuration is based on two PV power plants and one hydroelectric plant, including 14.4 kWp of PV generators and 20 kW of hydroelectric generators, respectively. This configuration was economically viable from the point of view of the investors, with a profitability index of 1.36, and, at the same time, it is aligned with the social purposes of the renewable energy community. [PERSON] et al. [5] assessed the impact of electric vehicles on the design and effectiveness of electric distribution grids with distributed generation. The aim of the work is the analysis of the technical limitations of the current networks and how transformers and lines will be able to address the increasing use of electric vehicles. The critical issues were observed, with special attention paid to urban networks rather than rural ones. Thus, future significant investments are required to achieve the full availability of high-powered charging stations. The authors state that the increasing power demand from electric vehicles represents a critical issue for the grid, mainly because their highest demand occurs during the typical consumption peaks of residential customers. Electric demand-side management strategies, considering a change in the behavior and use of electricity of customers, were proposed. [PERSON] et al. [6] presented an economic assessment of solar-powered residential battery energy storage systems on Madeira to understand if energy storage devices under the current legislation and energy tariffs are profitable. In this work, the data of one year-long solar PV production and electricity demand measurements, considering two different battery control strategies, are used. The obtained results confirm the current highlights of other similar studies, i.e., that the storages for self-consumption only are not profitable until the average price of energy storage devices becomes lower than 256 \(\mathrm{\upmu}\)/\(\mathrm{kWh}\) (including the inverter price). [PERSON] et al. [7] propose a novel droop control strategy for setting a dead band value that varies with time in order to address the voltage problem against disturbance in a transmission system connected with a utility-scale PV system. Simulation results showed that an adaptative dead band, rather than a fixed one, is able to perform a flexible system operation against disturbance.