Abstract
Renewable energy communities (REC) are an increasingly interesting solution for all energy market stakeholders. In RECs consumers and producers come together to form energy cooperatives with a strong incorporation of renewables in order to make the market and energy trading more advantageous for both sides. This growing trend has been followed by several studies aimed at understanding which are the best models for energy sharing within the community. This paper proposes different models of energy sharing within the community and evaluates their efficiency. Energy sharing can be based on constant coefficients or variable coefficients based on the net consumption of the self-consumers. This study proposes a new methodology based on a hybrid model. The results show the advantages and challenges of the individual energy-sharing models, showing that up to 41% of the energy imports from the grid can be reduced.

Abstract
The increasing number of vehicle to grid (V2G) charging stations connected to the electrical grid changes the characteristics of electrical distribution grids. Active power electronics introduces additional capacitance and inductance to the electrical grid and affects the frequency dependent grid impedance. This study shows the impact of a V2G charging station to the frequency dependent grid impedance up to 500 kHz. The LCL filter, the DC link capacitor and inductors cause parallel and series resonances. Resonance frequencies appear in a wide frequency range starting from 500 Hz up to 30 kHz. It is shown that the V2G charger can represent a source of supraharmonic emissions and the importance to consider supraharmonic emissions and the frequency dependent grid impedance to determine the impact of V2G chargers (active power electronics) to the electrical grid is outlined.

Abstract
This work addresses the wind farm (WF) optimization layout considering several substations. It is given a set of wind turbines jointly with a set of substations, and the goal is to obtain the optimal design to minimize the infrastructure cost and the cost of electrical energy losses during the wind farm lifetime. The turbine set is partitioned into subsets to assign to each substation. The cable type and the connections to collect wind turbine-produced energy, forwarding to the corresponding substation, are selected in each subset. The technique proposed uses a genetic algorithm (GA) and an integer linear programming (ILP) model simultaneously. The GA creates a partition in the turbine set and assigns each of the obtained subsets to a substation to optimize a fitness function that corresponds to the minimum total cost of the WF layout. The fitness function evaluation requires solving an ILP model for each substation to determine the optimal cable connection layout. This methodology is applied to four onshore WFs. The obtained results show that the solution performance of the proposed approach reaches up to 0.17% of economic savings when compared to the clustering with ILP approach (an exact approach).

Abstract

Abstract
This paper studies the suitability of the novel Light Quasi-Peak (Light-QP) measurement method to assess the high-frequency disturbances generated by the vehicle-to-grid (V2G) technology, by comparing the performance of the new method with respect to the standardized CISPR 16-1-1 method. For this purpose, the quasi-peak (QP) outputs obtained by both methods are compared, a statistical study of the differences in the spectral results is performed and the computational requirements of the two methods are evaluated. This paper demonstrates that the novel Light-QP method is a lighter technique to assess the QP amplitude of the conducted disturbances, as it requires 10 times less Fourier transforms and at least less than 90 % storage to process a 3 s length measurement. Furthermore, the QP outputs provided by the Light-QP method are comparable to the outputs of a digital implementation of the CISPR 16, since the differences in results are within the uncertainty limits defined in IEC 61000-4-30 standard for power-quality instruments in the CISPR Band A. The Light-QP method could be essential for the detection of the V2G disturbances in low-voltage grid, since it can be easily implemented in inexpensive power quality measurement instruments. The Light-QP method was presented in the IEC SC77 A WG9 for its possible inclusion in the next edition of IEC 61000-4-30 standard. © 2023 IEEE.

Abstract
The environmental protection and energy conservation concerns have spurred the development of new solutions in the automotive industry. This has led to the popularity of electric vehicles (EV) and Plugin hybrid electric vehicles (PHEV). On the other hand, this surge in popularity has created a challenge for the development of various new technologies and services, such as charging technology systems and stations. However, unidirectional charging offers hardware simplicity and easier interconnection and enable a G2V model, while bidirectional charging solutions enables G2V and V2G solutions, which can help stabilize AC power by utilizing the energy stored in the battery. This paper presents an EV battery charging system that uses a compact and straightforward bidirectional converter. The system can draw power from either traditional electrical sources or sustainable energy sources like photovoltaic modules, with the option of using lithium rechargeable batteries and supercapacitors as an Energy Storage System (ESS). Several Simulink simulations were conducted to investigate battery behavior under different power sources, and the results show the good effectiveness of the developed system, allowing it to be used in more comprehensive studies in the field of EV charging. © 2023 IEEE.