Danilo Sbordone

Technologies for smart grids: A brief review

In electrical power systems smart grid is widely recognized as the new solution that must be developed to manage distributed network tackling the increment of renewable energies. Through monitoring capability, data integration, effective communication, advanced analysis and system control the smart grid can meet the power demand as well as increase total efficiency and reduce consumption and costs. Many different technologies must converge to create a smart grid as a storage systems utilized as an energy buffer, telecommunication systems that can exchange data with sensors and actuators, advanced control systems that monitor the power grid and manage energy flows in real time. This paper reviews the state of the art of present application of these technologies in smart grids. The specific focus of the work is on telecommunication systems to have a monitoring through last smart metering application. The impacts and benefits of real time controls are investigated to improve the power efficiency, security and quality.

Efficient Energy Management in Smart Micro-Grids: ZERO Grid Impact Buildings

In a smart micro-grid (MG) each generator or load has to take part in the network management, joining in reactive power supply/voltage control, active power supply/frequency control, fault ride-through capability, and power quality control. This paper includes a new concept for building integration in MGs with zero grid-impact so improving the MG efficiency. These aims are shown to be achievable with an intelligent system, based on a dc/ac converter connected to the building point of coupling with the main grid. This system can provide active and reactive power services also including a dc link where storage, generation, and loads can be installed. The system employed for validation is a prototype available at ENEA Laboratories (Italian National Agency for New Technologies). A complete and versatile model in MATLAB/SIMULINK is also presented. The simulations results and the experimental test validation are included. The trial confirms the model goodness and the system usefulness in MG applications.

EV charging stations and modes: International standards

In recent years, Electric vehicles (EVs) are receiving significant attention as an environmental-sustainable and cost-effective substitute of vehicles with internal combustion engine, for the solution of the dependence from fossil fuels and for the saving of Green-House Gasses emission The present paper deals with an overview on different types of EVs charging stations and a comparison between the related European and American Standards. The work includes also a summary on possible types of Energy Storage Systems (ESSs), that are important for the integration of EVs fast charging stations of the last generation in smart grids. Finally a brief analysis on the possible electrical layout for the ESS integration in EVs charging system, proposed in literature, is reported.

A flexible Customer Power Device for energy management in a real Smart Micro-Grid

In the present paper an overview on Customer Power Devices (CPDs) for application in Smart Micro-Grid (MG) is reported. A particular attention is given to a real CPD equipped with an Energy Storage System, consisting in Lithium batteries, able to perform also functions of Distribution Static Compensators (D-STATCOM). Its typical layout, its main components and its possible functions are reported. A special focus is on its control modes and strategies for the energy management in a Smart MG and on its Battery Management System (BMS). The main figures of a real Smart MG, where the CDP is located, for active and reactive power service, are finally reported.

Reactive power control for an energy storage system

In last years, the power system operators are tackling many challenges for the renewable energies integration on the grid. Further, the expected increase of electrical demand due to the uncoordinated contemporary charging of a huge number of Electric Vehicles (EVs) can create chaotic phenomena with a negative impact especially on the distribution network. Help can be offered by the deployment of Smart Grid technologies, such as Smart Metering Systems (SMSs), Information and Communications Technology (ICT) and Energy Storage Systems (ESSs). In particular, in Micro-Grids, Battery ESSs (BESSs) can play a fundamental role and can become fundamental for the integration of EV fast charging stations and distributed generations. In this case the storage can have peak shaving, load shifting and power quality functions. The ESSs can provide ancillary services also on the grid as the reactive control to adjust the power factor. In the present paper, a monitoring control program to manage the reactive power of a real ESS in a Micro-Grid has been implemented. The system is a prototype, designed, implemented and now available at ENEA (Italian National Agency for New Technologies, Energy and Sustainable Economic Development) labs. A wide experimental activity has been performed on the prototype system in order to test this functionality for the integration in a bigger Smart Grid available at the same ENEA labs including the Micro-grid. The integration has been possible, thanks to the free ICT protocols used by the researchers and which are described here. The results of the experimental tests show that the system can have good performance to adjust the power factor in respect to the main distribution grid and an EV charging station.

D-STATCOM with energy storage system for application in Smart Micro-Grids

The paper focus is on the application of Distribution Static Compensators (D-STATCOM) in Smart Micro-Grid (MG). First of all, Smart Grids concept is introduced and the main definitions on the Smart MG are given. Afterwards, an overview on D-STATCOMs is reported, pointing out their layout, components and possible functions, in presence of energy storage system or not. Finally the problem of management of these devices for application in Smart MG is analysed, with a particular focus on the choice of the communication technologies for data exchange with an Energy Management System (EMS).

Energy savings in metro-transit systems: a comparison between operational Italian and Spanish lines

For transportation in large cities, new technologies that impact the operation of metro-transit systems are being developed. The energy efficiency in metro-transit systems is a key topic that is being studied in order to reduce both consumption and costs. A review on approaches to managing the energy recovered from train braking is reported. Then, energy performance indexes are presented. Their assessment is possible due to highly specialized simulation tools that have been developed at the University of Rome Sapienza and Comillas Pontifical University, Madrid. The indexes are used to perform a comparison between an operational metro-line in Spain and one in Italy. The results confirm their accuracy and significant improvements in energy efficiency and environmental effects are presented.

Sustainable Energy Microsystems for a Smart Grid

The paper deals with the proposal of a new architecture, called Sustainable Energy Microsystem (SEM), for a smart grid project in urban context. SEM includes energy sub-systems (SS) currently independent, such as high efficiency buildings, sustainable mobility systems (Electrical Vehicles and metro transit-systems), dispersed generation from renewables and Combined Heat and Power units. The present paper includes the description of the main SEM elements and some results of an energy analysis on each subsystem, showing the effective possibilities of integration, aimed to energy saving and environmental sustainability.

A comparison of two innovative customer power devices for Smart Micro-Grids

The paper presents a comparison of two prototypes of innovative Customer Power Devices designed for applications in Smart Micro-Grids. The devices are both equipped with Energy Storage Systems, consisting in Lithium batteries and have been assembled, independently, by the DIAEE of the University of Rome “La Sapienza” and the DEIM of the University of Palermo in collaboration with the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA). In the paper, the characteristics and the operating modes of the devices are examined and some consideration on their application in Low Voltage Smart Micro-Grids are provided.

Design of a fuzzy-based control system for energy saving and users comfort

Building automation systems (BAS) allow automated control of equipment and eventually control of indoor conditions. Indeed, BAS are becoming a powerful tool to improve the energy performance and occupant comfort, introducing the concept of “intelligent building”. At this regard, there is a need to build a knowledge base and to develop suitable algorithms for a smart management. Fuzzy logic is a valuable candidate for building robust algorithms. The aim of the present work is to demonstrate that a fuzzy logic approach is able to optimize the level of energy performance and comfort taking advantage of solar energy and BAS in an office space. In fact, solar energy can be used in the form of daylight and solar heat gain, benefiting both energy performance and psychophysical comfort, provided that dynamic façade elements and integrated multi criteria decision making methods are used. In this paper has been developed a virtual model of a smart office room (SOR), equipped with dynamic shading, lighting and air conditioning control system. Different scenarios were considered as follows: i) control versus no-control; ii) economy versus comfort mode; iii) summer versus winter scenario; iv) fluorescent versus LED lighting; v) dimming versus switching lighting control. The configured control model makes comfort mode energy performance similar to that of economy mode, thus demonstrating that the use of solar energy and BAS benefits energy saving and comfort as well. In addition, both economy comfort mode exhibited a better energy performance than non-controlled scenarios. In conclusion, the proposed model is a valuable tool to optimize comfort features and yet decreasing the energy demand.