Thanks to a number of theoretical lectures, the student has the opportunity of learning the basic principles of energetic, exergetic and second law analysis of energy conversion processes as well as the main components utilized in the energy storage devices. Those lectures will also help students to have a coherent vision of the matter and make an aware use of design tools that are discussed during the course. We expect students to acquire the ability of estimating energetic and exergetic performance of both reversible and irreversible energy conversion and storage systems. Such an ability is essential for helping students in strengthening their problem-solving attitude. Regarding the electricity transport and distribution, the students will acquire the knowledge on the structure of the electrical system. The students will be able to handle the fundamental variables of the electrical system (voltage, current and power, both active and reactive), recognize the main components of the electrical system (lines, transformers, converters and protection devices), and evaluating the performance of the last-mile electrical chain (transformer, line and load), also in the presence of power factor correction. All this will be pursued by: 1) case study discussion; 2) experiments in the laboratory (depends on availability during current year); 3) analysis and design of energy conversion and storage problems selected in collaboration with the lecturers.

Basic knowledge on thermodynamics, thermokinetics and chemistry. Complex numbers. Fundamentals of electrical circuits. Fundamentals of magnetic circuits. In any case, important know-how will be reminded and discussed in the introductory part of the course as detailed below.

The course topics can be categorized in the following five sections. For each section, the foreseen amount of dedicated time is also specified: Introductory part and reminders (10% of the total time): Introduction to the course and brief review of basic notions useful to the comprehension of physical phenomena underpinning energy conversion, transport and storage. Brief review of some of the most important relationships in applied thermodynamics. Brief review of the main heat transfer mechanisms, design of heat exchangers with and without fins. Basic reminders on chemical kinetics. Reminders of basic electrical quantities (voltage, current, active and reactive power). Use of Direct Current and Alternating current (single-phase and three-phase) in electrical applications. Calculation examples. Fundamentals of energy conversion (25% of the total time) Basic equations describing heat and mass transfer phenomena in continuum media with special focus on the conservation of mass, momentum, energy and entropy. Discussion on the integral equations for analyzing both closed and open energy conversion systems. Technical formulation of integral equations. Physical meaning of irreversibility. Correct calculation of irreversibility by practical formulas. Exergy balance in energy conversion systems. Exergy and internal exergy for simple material models (ideal gas and incompressible substances). The theorem of Gouy-Stodola. Physical meaning of exergy. Efficiency according to the second principle. Examples of exergy analysis. Exergy diagrams. Thermodynamic diagrams. Examples of applications. Fundamentals of energy transport (25% of the total time) Structure of the power system: production, transport, distribution and utilization. Voltage levels in the power system. Modeling of the electrical lines: PI-model and its simplification according to the voltage level. Voltage drop and power factor correction. Efficiency of the line. Structure and principle of operation of single-phase and three-phase transformers. Open-circuit and short-circuit test on the transformer. Equivalent circuit. Efficiency of the transformer. Structure and principle of operation of power converters. Short circuit currents (three phase, single-phase, phase-to-phase faults). Circuit-breakers in High Voltage, Medium Voltage and Low Voltage circuits. Examples of applications. Fundamentals of energy storage (25% of the total time) Introduction to the importance of energy storage. Overview on the most common and mature mechanical energy storage technologies: compressed air and pumped hydro-storage plants. Flywheels. Energy storage in gaseous springs. Gravity energy storage technologies. Fundamentals of lumped parameter modelling of different energy storage systems. Fundamentals of electro-chemical energy storage systems. The issue of deep cycling, depth of discharge, battery capacity and other main figures of merit of storage systems. Overview on the three forms of thermal energy storage. Materials and plant layout for sensible heat storage. First and second law efficiencies. Simplified energy and exergy analysis of stratified sensible heat storage. Classification of the most common materials for latent heat storage applications (organic, inorganic and eutectic). The choice of the optimal PCM material from the exergetic perspective. Discussion of ideal and real sorption thermal energy storage cycles. Simplified models for describing sorption phenomena (Dubinin-Astakhov and Langmuir). Numerical examples of sorption heat storage systems. Laboratories activities (15% of the total time) In addition to the above theoretical lectures, the following activities are foreseen. • Dedicated hands-on sessions on lumped parameter modeling of energy storage systems in Matlab and Simulink environment. • Detailed technical tour of the facilities at the Energy Center Lab. Starting from the thermal plant whose components are: open geothermal heat pump with groundwater well, connection to the urban district heating network, solar thermal collectors, sensible heat storage volumes. Other test beds may concern micro wind turbines, a photovoltaic solar system with an installed power of about 50 kW, a geothermal heat pump that exchanges heat with the ground, a solar concentrator, electrical storage systems with lithium ion batteries, sensible heat and latent heat thermal storage systems. A special focus will be placed on some of the systems mentioned, for which calculation/design exercises will also be carried out. • Visit to one of the MV/LV substations of Politecnico di Torino. The students will have the possibility to see all the components described during the lecture in a real layout, which will be helpful in the subject understanding.

- Notes provided by the lecturers - I. Dincer, M.A. Rosen, "Thermal Energy Storage Systems and Applications", John Wiley & Sons, 2nd Edition, 2011; - R. Schloegl (ed), Chemical Energy Storage, De Gruyter, 2013; - A. Bejan, "Advanced Engineering Thermodynamic", John Wiley & Sons, 1997; - A. Bejan, A.D. Kraus (Editors), "Heat Transfer Handbook", John Wiley & Sons, 2003; - Callen, H. B. Thermodynamics and an Introduction to Thermostatistics, 1998 - M. Ceraolo, D. Poli, Fundamentals of Electric Power Engineering, Wiley & IEEE, 2014.

Lecture slides; Lecture notes; Exercises; Video lectures (current year);

Exam: Compulsory oral exam;

The exam lasts around 30 minutes and consists of an oral discussion with the Exam Commission. The student will be asked 3 questions: One on the energy conversion part, the other on the energy transport and the last on the energy storage (or alternatively on energy generation by renewable sources). Each answer will be graded up to 11 points. The total score is given by the sum of the three parts. The minimum score to pass the exam is 18. Students exceeding 31 points will pass the exam “cum laude”. During the exam, it is possible to use pens, papers and calculators for sketching and as a support for the answers. No teaching material can be consulted during the examination. The exam aims at assessing that the expected learning outcomes as detailed above have been achieved and more specifically to which level the student: • Has understood the most important fundamental aspects of the course topics on energy conversion, transport and storage technologies; • Is capable to deal with practical aspects and ability in analyzing performance of energy conversion, transmission and storage technologies on specific cases.

In addition to the message sent by the online system, students with disabilities or Specific Learning Disorders (SLD) are invited to directly inform the professor in charge of the course about the special arrangements for the exam that have been agreed with the Special Needs Unit. The professor has to be informed at least one week before the beginning of the examination session in order to provide students with the most suitable arrangements for each specific type of exam.