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Public lighting systems consist in a complex of different technical systems: lighting, electrical, mechanical and electronic. The presence of electrical components and power lines exposed to atmospheric stresses and accessible to all citizens determines a situation of electrical risk that must be managed during the entire life cycle of the system: design, installation and maintenance, in order to guarantee the highest level of safety for all. The paper suggests energy and safety criteria useful for the optimized design of the system and to improve its maintainability. The prospected energy performance of the system can be considered as an important design criterion. The adoption of a class II insulation system needs special requirements for the check of its performance during the life. The paper suggests the adoption of a special smart panel with a special component useful to make the periodic insulation verification.

The paper concerns the analysis and simulation of the behavior of the total ground potential around the grounding systems of the installation-on-pole (PTP and disconnector) and MV/LV substations in order to define and quantify the best possible safety distances in terms of “acceptable risk” around the grounding systems. The analysis was conducted by adopting the Maxwell method for the analytical simulation of the grounding systems. By the analysis of the databases of the main Italian distribution system operator, each one with over than 300,000 data about the Italian grounding systems, the paper proposes a macroscopic result to define an “acceptable risk zone” by taking into consideration a weighted average value for the fault current and a medium value for the ground resistivity.

The modularization of industrial plants concerns the decomposition of the system into multiple subsystems that are built in yards located in different areas of the world and then assembled on the construction site. This design philosophy allows to reduce construction costs and schedule. Unconventional plant solutions can make the most of this system concept also in the electrical sector. In this paper, an alternative architecture for the electrical distribution is proposed. The suggested scheme allows the reduction of the number of equipment and the weight of the system resulting an optimal solution for a modularized system. The results are achieved by decreasing the required installed power and the weight of the used copper for the cables.

This paper investigates a general description of a hybrid energy hub (HEH) including multiple energy carriers, such as electricity, hydrogen gas, and heating. The real hybrid energy hub model is based on a conceptual approach for the inclusion of distributed resources. Couplings between the different energy carriers are regarded explicitly, enabling investigations in power and energy flow. The model consists in a smart microgrid with multiple and hybrid energy sources, storages and loads, including electric vehicles charging stations and hydrogen, completely controlled and monitored by a supervisory control and data acquisition platform (SCADA). All the components communicate by an open protocol to the main control for management, analysis and diagnostic. The completely open and flexible structure makes this platform ideal for the conception, simulation and experimental development of innovative systems in the field of microgrids and hybrid energy systems.

In this article, a cost-based mathematical optimization is used to evaluate the optimal amount of imported power from the public main grid to a private microgrid (MG), that is the “LAMBDA lab MG” testbed placed at the Sapienza University of Rome. In this regard, this article considers five tests based on using different sources, including a photovoltaic (PV) array, an emergency generator set, a fuel cell, and the main grid, for load satisfaction. The “LAMBDA lab” can be considered as a “multisource multioutput energy hub” with three optional sources and both electrical and heat demands in output. This article considers PV production and load demand as indeterministic parameters and evaluates the problem under uncertainties. As a result, a stochastic programming model is defined, and a powerful optimization function is used to reach the optimal power received from the main grid. Besides, information gap decision theory is used to model the robustness of the problem against uncertainties associated with renewable generation units (PV system) and electricity loads applied on a real case for the first time. In the result section, the contribution of each source in electrical and heat load demands is presented in addition to the cost of each test by evaluating the effect of demand response of 15%. Finally, a comparison between the stochastic programming method and IGDT has been accomplished.

The concept of energy communities is promising to empower alternative ways of organizing and governing energy systems in the next future. Energy communities will provide to end-users democratic, open access to the grid, and collective self-consumption. They will encourage decentralization and promote distributed renewable energy sources applications. Energy communities are widely recognized to be a fundamental step for a sustainable energy transition. The authors present an innovative power-sharing model that can be easily implemented in new and existing multi-apartment buildings. It allows end-users to collect into a democratic energy community and enjoy beneficial ecological effects and economic benefits.

This paper investigates the feasibility of a recently proposed building energy community scheme where the energy of a single rooftop photovoltaic system is shared by costumers with a open and democratic participation. A Simulink/Matlab model is developed where we focus on the implementation and control aspects of all the relevant components, e.g., voltage source inverters for ac grid connection, dc/dc converter with maximum power point tracking strategy, inverters control for energy sharing among end-user. Preliminary results confirm the efficiency and flexibility of the proposed scheme.

The new concept of renewable energy communities introduced by the Revised European Directive on the promotion of renewable sources (2018/2001) has opened new possibilities for microgrids. In fact, it permits to enhance the value of the energy produced by renewable sources sharing it inside an “energy community” and to increase the social welfare. In the present paper, the authors investigated about the actual legislation framework on energy communities at European and Italian level, highlighting regulatory problems and barriers that are delaying their constitutions. The authors propose a “power sharing model” (PSM) useful for energy communities and based on the sharing of renewables and other energy services. PSM is suitable both at building level and for larger communities. PSM has been analyzed through a case study that regards the preliminary study of a smart microgrid that should be realized in Campobasso, Italy, to connect buildings of the public administration. This scenario was investigated through a simulation conducted in Simulink environment were the control strategy was implemented, and the results were compared to a traditional configuration for renewable sources integration.

The operation of Photovoltaic (PV) system mainly rely on appropriate modeling of solar cells and optimum approximation of parameters associated with them. Recently, various hybrid, numerical and analytical techniques were proposed to extract optimal parameters of PV cell. This paper presents an efficient approach, A Simulated Annealing Inertia Weight Particle Swarm Optimization (SAIW-PSO) for optimal estimation of PV parameters for double and single diode models. In addition, fitness indicator is guided using the Newton Raphson Method (NRM) that supports SAIW -PSO to explore the optimal solution. The premature convergence problem of typical PSO is resolved by the proposed framework. The strength of proposed approach is validated under standard test conditions (STC) on RTC France Silicon Solar cell. The SAIW-PSO is capable to explore optimum solution in smaller number of iterations and less computation time. The obtained results clearly depict that the proposed framework is fast, efficient and much accurate for PV cells parameters approximation.

The paper proposes an innovative system of supervision and data acquisition, oriented to fire safety through a dynamic risk analysis, called SCADRA (Supervisory Control and Dynamic Risk Analysis). SCADRA achieves operation and management benefits for safety, functionality and energy optimization, by means of dynamic control and monitoring measures. A “Smart Tunnel” can be defined as a model where technical systems are designed and installed in an advanced way, by using digital components and sensors. SCADRA has been developed to offer a complete tool (human machine interface HMI) for real time monitoring of tunnel safety by tunnel operators, integrated with the innovative dynamic risk analysis. SCADRA offers compensatory and/or supplementary safety measures for emergency management and supports fire rescue teams that are operating in tunnel in which some requirements couldn't be realized.

The evolution of the building automation and control systems (BACS) systems presents the challenge of defining new concepts for a clear and unambiguous definition of functionalities. While for traditional electrical systems it is possible to unequivocally infer functionalities from wiring diagrams and component characteristics, in BACS systems this may not be so immediate. A comprehensive description of the functionalities of such systems may require additional descriptors, so as to also consider logical connections among devices, as well as their configurations. Designers of BACS systems must therefore become familiar with software that may be used to properly express the logic functionalities of the system, and be able to provide system integrators with pertinent details for the hardware settings. In BACS, a logical layer (setting and addressing) is superimposed on a physical layer (wiring). The logical layer determines the functionality of the system. Software should allow the implementation of networks parameters with any communication standards (e.g. KNX, proprietary systems, etc.) and be transparent to the designer. This paper critically reviews the state-of-the-art in BACS, and examines major parameters that may be universally applicable to both KNX systems, as well as to proprietary systems with gateway (e.g., Xiaomi, Google Home, etc.). BACS is one of the most important enabling technologies for the creation of microgrids for smart buildings and energy communities.

The paper shows a case study of high efficiency lighting system realized in a library room at the University of Rome, Italy. The paper describes the lighting and control systems and highlights the impact on the energy performance. The adoption of LED modules and building automation approach permitted to obtain high level of performance both for lighting comfort and for energy performance. The library was divided in different zones. In each zone the optimal control was adopted. The energy results demonstrate that LED renovation coupled with electronic controls permit to obtain high values both of energy savings and performance.

The home and building automation systems evolution, creates the necessity to define new formalities for the clear and univocal description of their functionalities. To describe the operation of such a system, it is necessary therefore to add a further level that keeps in mind the logical connections among devices and their configurations. The addition of this level makes unambiguous the description of the plant functionalities. From the current state of the art it arises the demand of creating a software that allows the home automation system designer to exclusively focus on the logical functionalities of the system, furnishing to the system integrator the general details for the hardware settings. Particularly, the new network implementation details (KNX system, proprietary systems, etc.) will be completely transparent to the designer. The objective is to get a project documentation that is possible to adapt both for KNX home automation systems and for proprietary systems managed by a gateway (Xiaomi or Google Home).

This paper presents a strategy to avoid peak demand rising and energy management due to existing cranes at container terminals (CT). The new generation of the Ship to Shore (STS) cranes installed at the port of Long Beach (POLB) are equipped with the capabilities to absorb up to 90% of the regenerative energy (RE). Hence, a percent of RE is fed into the dc-bus in an STS Crane and deliver to the Ultracapacitor (UC) bank energy storage system (ESS). As an effective method, UC sizing is able to do the local peak shaving in each STS Crane and then with the remaining percent of the RE by the duty cycle coordination for the STS group Cranes the overall peak power minimization in point of delivery has been reviewed based on PSO algorithm. Results in MATLAB shows the two proposed methods can reduce the peak power demand and increase the percentage of the utilization energy factor (UEF) in STS cranes.

The technological innovation of systems in tunnels allows to reach high levels not only in energy efficiency but also in safety, where the legislation requires safety measures based on systematic considerations of all aspects of the system (infrastructure, operations, users, vehicles).In many existent tunnels, some structural safety measures could be implemented only through technical solutions with a disproportionate cost because of difficulties due to old infrastructures, unfavorable orographic situation or tunnels in sequence in wich simultaneously road works could cause a paralysis of traffic with unbearable economic and social costs. Therefore, a new layout of the SCADA system, able to perform a Dynamic Risk Analysis (DRA), has been developed to achieve immediate and effective benefits through the implementation of operational measures in Smart Tunnels in which advanced systems and sensors are installed. DRA can be associated with Energy Management Analysis (EMA) in order to perfectly fits within the "Industry 4.0" new European approach: through low costs it is possible to know real time what happens inside the tunnel, the environmental conditions, traffic data and system status (Smart Production), to apply operational measures in order to ensure the safety required (Smart Services) and to operate in energy saving mode whenever possible (Smart Energy).

Buildings with mixed residential and commercial units show relevant power peak that are further increased by shifting from gas-driven systems to an electric source. The proposed solution is to organize a microgrid for such type of buildings, aggregating different users with a common electric distribution system with a single connection to the grid, a local common generation, and a common heating/cooling system (electric driven). This approach upgrades a group of independent small users with rigid loads and chaotic behavior to a large user with a flexible and controlled profile. A central building automation control system managing all built-in technical systems and smart appliances may control the load, minute by minute, shifting in time shiftable and controllable loads, and merging different kinds of loads, obtaining a flatter diagram. The authors consider the suggested approach convenient to realize a demand side management (DSM) for residential/commercial buildings. distribution system operator (DSM) exploits the flexibility of smart appliances and the thermal inertia of the structure, by imposing local and central set points of heating and cooling systems, according to actual global net load and generation at a given moment. In this paper, main aspects of the proposed control system are presented and simulations for a given case study with a local photovoltaic system generation are provided. Results show that this approach may lead to a power peak reduction up to 20% even in the unfavorable case of combining commercial and residential units. Moreover, full self-consumption of locally generated energy from renewable energy systems may be achieved.

Considering the highest power demand by Ship to Shore (STS) cranes in pier E at the port of Long Beach, designing a proper control system can harness the peak load increasing. In this paper, tw o strategies have been used for the peak load shaving. First, demand side management (DSM) in order to peak power demand minimization by duty cycle coordination between STS cranes based on PSO algorithm and in the second part utilization of Flywheel Energy Storage System (FESS) to make a power balance between generation and demand side. Results in MATLAB related to reference data shows the proposed method can reduce the peak power demand in the STS group cranes and provide a proper power balance between generation and demand.

Residential and non-residential buildings are responsible for approximately 40% of energy consumption and CO2 emissions in the EU. Considering that almost 75% of the building stock in EU is energy inefficient, the European energy policy promotes the improvement of the energy performance of existing buildings by introducing the innovative model of nearly zero energy building (nZEB). In the nZEB model, local energy sources (generation, storage and load management), building automation (BACS) and electronic monitoring of technical building systems (TBS) play a fundamental role. In electric systems, smart grids are a key feature of future energy scenarios, with the overarching goal of better aligning energy generation and demand. The challenge is the role of the users. The nZEB model with its “smart microgrid” can represent an effective driver according to the new policies of user's aggregation. In this framework demand side management (DSM) strategies can be implemented. The paper presents an innovative approach to use BACS present in nZEBS not only to increase the efficiency of TBS but also to operate an energy storage by heating systems for DSM strategies.

This paper introduces a characterization of grounding systems (GSs) and defines their condition of “conventionally safe” and “intrinsically safe.” A single GS and a set of GSs are intrinsically safe if they guarantee touch/step voltages permanently permissible for an assigned ground fault value. A new definition of global grounding systems (GGSs) is proposed, revising that offered by the Standards IEC 61936-1/EN 50522. A safety criterion, useful for urban and industrial areas with reduced accessibility, allows identifying the safety zone of influence, and the intrinsically safe condition of a single GS and of a GGS, constituted by a set of interconnected single GSs.

Contrary to many expectations, the development of smart (mini-)grids is slow, notwithstanding drastic improvements in innovative technologies, and the reasons for this are not strictly technical. The problem lies in regulatory barriers. Moreover, the current business models accommodate utilities more so than customers. Net metering is a key enabling factor for smart (mini-)grids. This article addresses the economic benefits of net metering for residential customers. Energy demands for individual apartments and common areas are calculated using the daily energy-consumption behavior of occupants for typical days of each month of the year. Photovoltaic (PV ) generation is estimated for a residential building in Italy. The proposed net-metering scheme is applied on the aggregate energy demand of a selected building. The current energy billing without modifications is compared to the case in which net-metering tariffs are applied to the billing. Results show that noticeable savings can be obtained in the net-metering case.

International Standards define a Global Earthing System as an earthing net created interconnecting local Earthing Systems (generally through the shield of MV cables and/or bare buried conductors). In Italy, the regulatory authority for electricity and gas requires distributors to guarantee the electrical continuity of LV neutral conductor. This requirement has led to the standard practice of realizing “reinforcement groundings” along the LV neutral conductor path and at users’ delivery cabinet. Moreover, in urban high-load scenarios (prime candidates to be part of a Global Earthing System), it is common that LV distribution scheme creates, through neutral conductors, an effective connection between grounding systems of MV/LV substations, modifying Global Earthing System consistency. The aim of this paper is to evaluate the effect, in terms of electrical safety, of the aforementioned LV neutral distribution scheme when an MV-side fault to ground occurs. For this purpose, simulations are carried out on a realistic urban test case and suitable evaluation indexes are proposed.

In the modern power system, characterization of customer's demand plays a vital role for Demand Side Management. Demand flexibility information, extracted from the aggregate demand behaviour of customers, presents more comprehensive picture for the aggregator or system operator. There is an existence of diverse flexible time slots during a day in different time periods. Due to the diverse energy consumption behaviour of the residential customers, extraction of flexibility and its associated potential time durations is a challenging task. To extract flexibility information from aggregate residential customers, a flexibility indicator is formulated in this paper. Information presented gives an indication about flexible time slots in terms of numerical value that is useful for a system operator or an aggregator for demand side flexibility assessment and this will lead to design and initiate DSM programs.

This paper presents an output power smoothing method by a coordinate control of machine side converter and grid side converter for permanent magnet synchronous generator (PMSG) based wind energy conversion system (WECS). The WECS adopts medium voltage source converter with AC-DC-AC configuration. The output power fluctuations are compensated using direct torque control based maximum power point controller and voltage oriented control. The DC link voltage is controlled using grid side controller and the maximum power is extracted using the machine side controller of the wind turbine. The proposed controller provides effective solution for grid integration and constant power flow from the generator system to grid system. Simulation results are presented and analysed the performance of the control strategies implemented in the system.

The paper describes a measurement campaign conducted at the Engineering Department of Astronautics, Electrical and Energetic, Sapienza University of Rome. Starting from measurement campaign, in the context of building an urban microgrid, a PV plant and a energy storage system has been proposed. The measurements were conducted in two relevant period of the year in order to know the power consumption of the facility. The knowledge of total energy demand by electrical loads allows the identification of most efficient strategies for energy utilization by using the PV production and energy storage.

It is well known that the control of energy consumptions in a building or in an organization enables to improve the energy performance (EP). The measurement plan defines the procedure for the design, deployment, utilization, maintenance and improvement of a distributed measurement and monitoring system (DMS). A DMS is able to measure and analyze the EP of the organization according to factors that influence the operation of the site. The paper suggests a method of assessment of a DMS based on different criteria. The paper focused on the criterion of the Level of Coverage. The authors suggest the definition of a Level of Coverage Numeric Indicator (LoCNI) that evaluates the capacity of the DMS to track consumptions by zones and by uses.

Buildings with mixed residential and commercial units show relevant power peak that re further enhanced by shifting to electric source of nowadays gas-driven systems. The proposed solution is to organize a microgrid for such kind of buildings, aggregating different users with a common electric distribution system with a unique connection to the grid, a local common generation and a common heating/cooling system (electric-driven). This approach upgrades a group of independent several small users with rigid loads and chaotic behavior, to a large user with a flexible and controlled profile. A central building automation control system (BACS) managing all built-in technical systems and smart appliances may control load minute by minute, shifting in time plannable and controllable ones merging different kinds of load, obtaining a flatter diagram. The authors consider the suggested approach convenient to realize demand side management (DSM) for residential/commercial buildings. DSM exploits the flexibility of smart appliances and the thermal inertia of the structure, by imposing local and central set-points of heating and cooling systems according to the actual global net load and generation at a given moment. In the present paper, main aspects of the proposed control system are presented and simulations for a given case study with local PV generation are provided. Results show that this approach may lead to power peak reduction up to 20% even in the unfavorable case of combining commercial and residential units. Moreover, full self-consumption of locally generated energy from RES may be achieved.

Total transfer capability analysis of power system is currently a critical issue in both planning & operating of systems. These issues mainly occur due to increase in area and interchanges among utilities. To reduce the flows in heavily loaded lines, Flexible Alternating Current Transmission System (FACTS) devices is used, this results in increased transfer capability, improve stability of the network, low system losses, and fulfill contractual required by controlling the power flows in the network. To achieve parameters FACTS devices are placed optimally and is done with the help of reduction of total system reactive power loss sensitivity indices analysis method and real power flow performance index sensitivity indices analysis method. Thyristor-Control-Series-Capacitor (TCSC) is used as a FACTS device in the proposed sensitivity analysis method. To decide priority of line for placing TCSC, soft computing technique "Fuzzy logic method" is employed. The performance evaluation of proposed sensitivity analysis methods is done using electrical IEEE-5 bus system. The sensitivity indices are programmed using Matrix Laboratory.

Distributed Generation (DG) brought new challenges for protection engineers since standard relay settings of traditional system may no longer function correctly under the new conditions of DG. The extreme case is coordination loss between primary and backup relays. The directional overcurrent relay (DOCR) which is the most implemented protection device in the electrical network also suffers performance degradation in presence of DG. Therefore, the paper proposes the mitigation of DG impact on DOCR coordination employing adaptive protection scheme (APS) using differential evolution algorithm (DE). The impacts of DG prior and after the application of APS are presented and a new mitigation scheme is proposed.

This paper introduces a characterization of a single Grounding System (GS) or a set of interconnected GSs, according to their safety level and defines their condition of “conventionally safe” and “intrinsically safe”. GSs or a set of them are intrinsically safe, if they guarantee safe touch/step voltages permanently permissible for an assigned ground fault value. It is proposed a new definition of Global Grounding Systems (GGSs) revising that offered by the Standards IEC 61936-1/EN 50522. The paper suggests a safety criterion, useful for urban and industrial areas with reduced accessibility, that allows to identify the safety zone of influence and the intrinsically safe condition of a single GS and of a GGS, constituted by a set of interconnected single GSs.

The adequacy of a Grounding System (GS) to the safety conditions has to be periodically tested by measurements. The test methods and techniques used to verify the electrical characteristics of the GS include the measurements of step and touch voltages. The goal of the test is to verify that touch voltage and step voltage remain below a safe value in all the zones of the installation. The measurements can present some operational difficulties. The purpose of this paper is to present the procedure, step-by-step, of a practical method of measuring touch/step voltages in grounding systems located in urban or industrial areas with reduced accessibility. The suggested method uses auxiliary current electrodes located at short distances. This paper demonstrates by test measurements done in a real case that the method provides conservative results.

Lightning discharges are able to damage electric and electronic devices that usually have a low protection level and are influenced also by current or voltage pulses with a relatively low energy, such as those induced by lightning currents. Home automation systems contain electronic parts and hence are more vulnerable than normal electric systems. The risk of damage can be assessed by using the procedure described in the standard series IEC 62305. Then, protection measures can be characterized, if necessary, in order to reduce the value of the economic loss to an acceptable level.

The present paper presents the preliminary results of the ongoing Italian METERGLOB project on the contribution given by the exposed conductive parts to a Global Grounding System. One of the expected results of METERGLOB is to carry out guidelines for the identification of a Global Grounding System. These guidelines must be defined on the basis of the definitions and methods present in the current international standards on grounding and safety. In the paper some definitions and elements to be taken into account for the identification of a Global Grounding System are given.

The current attention to energy management leads to the necessity to tack new challenges for a best integration of renewable energies, mobility systems and new technologies for the energy efficiency, creating several micro grids with an active interaction with the main energy distribution networks. The integration of more energy systems seems to be the key of the future development and at present it is mainly applied to industrial systems, where Virtual Power Plants (VPPs) are very promising instruments for promoting an effective integration. Since the built environment is one of the biggest consumers of primary energy worldwide and considering the complexity of some residential and tertiary users, the paper proposes the application of the basic principles of the VPP to the building environment introducing new functions typical of the urban context. The paper shows how an optimization algorithms, traditionally used in the industrial sector to schedule and operate a cluster of energy resources, can be successfully adapted also to residential and tertiary frameworks, proposing the aggregation of several energy sub-systems (SS), generally operated as independent, in a single one named Sustainable Energy Microsystem (SEM).