Luigi Martirano

A smart lighting control to save energy

In Europe the amount of the electrical energy used in illuminating the interiors of medium and large buildings is considerable of about 40%. Energy saving actions could follow two basic directions: efficiency and effectiveness: efficiency, by new more performing equipment (lamps, control gear, etc.) and by utilization of improved lighting design practices (localised task lighting systems); effectiveness by improvements in lighting control systems to avoid energy waste and by adopting a technical building management system (maintenace and metering). By controlling the lighting in such a way that the lighting level is always accurately matched to the actual need allows to save on the energy costs and to improve the human comfort and efficiency. Establishing an integrated lighting control concept is a very important part of the lighting design process. Directly controlling and managing energy consumption it is possible to reach high effectiveness in energy management.

Lighting systems to save energy in educational classrooms

In educational buildings a significant component of the energy used is spent in illuminating the interior of the building. As the energy costs rise, increasing effort has gone into minimizing the energy consumption of lighting installations. This effort could follow three basic directions: new more efficient equipment (lamps, control gear, etc.), utilization of improved lighting design practices (localised task lighting systems), improvements in lighting control systems to avoid energy waste for unoccupied and daylight hours. By controlling the lighting in such a way that the lighting level is always accurately matched to the actual need allows to save on the energy costs and to improve the human comfort and efficiency. Establishing an integrated lighting control concept is a very important part of the lighting design process. The paper describes two different smart control systems designed according the same concept but with different components, for the lighting systems in two classrooms at the Engineering Faculty of the Universty of Rome Sapienza. The installations are realized according to a research project about the assessment of the impact of lighting control systems in electrical energy consumption and energy commitments. The results are useful to compare the two different control approaches (switching and dimming) and the two different kind of actions (with or without luminaries upgrade) in order to analyze costs, energy consumption and comfort. The two different control technologies are compared with respect to a third classroom without smart control, used as reference for evaluations.

Impact of building automation, controls and building management on energy performance of lighting systems

In a lighting system design to estimate the actual energy efficiency of lighting control systems is an important goal since an accurate evaluation could help and guide designers towards the most appropriate control system. This paper analyzes the methodology for calculating energy consumption for lighting systems and the impact of the Building Automation and Control Systems (BACS). It promotes a comprehensive ecodesign of lighting systems consisting in the adoption of the appropriate lighting components and the adaptive partitioned architecture of electrical distribution system and lighting system in general and independent local systems. It allows structurally to satisfy in each sub-area lighting and energy performances and to provide a basic efficient control system suitable for a manual or automatic regulation.

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.

Sustainable Energy Microsystem (SEM): preliminary energy analysis

The paper deals with innovative idea that is to move beyond the current concept of smart grid, proposing a new architecture, called Sustainable Energy Microsystem (SEM). The proposed design includes energy sub-systems currently independent: high efficiency buildings, sustainable mobility systems, dispersed generation from renewables and Combined Heat and Power units. In the paper, the authors show the main figures of the SEM and report the first results about the necessary preliminary energy analysis.

Ecodesign of Lighting Systems

This article analyzes the methodology for calculating the energy consumption of lighting systems and the impact of building automation and control system (BACSs). The article also promotes a comprehensive ecodesign (ED) of lighting systems, consisting of the adoption of appropriate lighting components and adaptive-partitioned architecture for electrical distribution systems and lighting systems in general and independent local systems.

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.

Daylight Impact on Energy Performance of Internal Lighting

Daylight in interior offers a considerable contribute of energy allowing to reduce the level of electric lighting. The key to design an integrated lighting system is the electric lighting control strategy. An optimal lighting system has to consider the different presence of daylight in the zones to arrange the most favorable luminaires layout. An automatic control system could be employed to switch or dim selected groups of luminaires. The paper suggests a criterion to evaluate the yearly daylight impact on energy performance of internal lighting according to daylight availability, the lighting system layout and the control system arranged. The evaluation is useful for designers to estimate the operation costs in reference to the initial costs.

Prospected Evolution for Low Voltage Customers: Ecodesign of the Electrical Distribution System

In the last years important improvements are developing in the European Union EU electrical systems: the process of electrical market liberalization, extended to all the customers, small and residential included, and a strong encouragement towards the energy saving and the installation of small renewable power sources. The actual distribution system for low voltage customers appears inadequate to comply with these improvements. The electricity market has to recognize the constitution of union of Customers Bunches. For an actual safety progress, a comparative analysis of international electrical approaches on distribution systems will promote an understanding of their similarities and differences and the design of new integrated common solutions. The authors suggest the ecodesign of the residential and commercial low voltage distribution for the next future that allows to accomplish the goals about safety, power quality, emergency systems, load shedding and energy management. The ecodesign requires imagination and intelligence that can reveal opportunities, expose risks and support strategic decision making.

Arc-fault protection of branch circuits, cords, and connected equipment

In electrical power systems, the fault frequently involves arcing and burning of wiring exposed to mechanical damage and other insulation stresses including wiring not fixed and connected by flexible cords and cables. IEC Standard 60364 ends the design of electric power systems at the outlets of branch circuits or at the fixed equipment. A complete design should include the connections of portable equipment and of extension cords (as requested by NFPA 70) that are exposed to arc faults and may cause fire and/or electric shock hazards. Since cords supplying Class II equipment are without a grounding protection conductor, the failure of the double insulation, caused by external damage, is unlikely to be easily detected as a ground fault. Protection must be provided to prevent the fault from extinguishing itself without being detected and remaining energized, thus presenting an electric shock hazard by direct contact with a live part, rendered accessible after local insulation failure. The authors highlight this worst case and suggest the protection achieved by wiring the circuits, particularly extension cords, with special power cables. Ground-fault forced cables (GFFCs) convert a line-to-line fault into a line-to-ground fault, that will be detected and protected by ordinary ground-fault protective devices. By adopting the GFFC type of cables internally to Class II equipment, the disconnecting protection could also be extended to equipment.