Lecturer: Alessandro Croce   Roberto Preto   Giuseppe Venchi  

Course name: Renewable Energy Sources
Course code: 504274
Degree course: Ingegneria Elettrica
Disciplinary field of science: ING-IND/03,ING-IND/32
The course relates to:
University credits: ECTS 9
Course website: n.d.

Specific course objectives

The aim of the course is to give an overview, as complete as possible, about energy production from renewable sources. The course is composed of three modules, worth 3 CFUs each, that are: biomass energy systems, wind energy systems and photovoltaic energy systems. Each module will introduce the working principle of the corresponding system and will give the theoretical and practical knowledged required to design te plant. Norms and regulations will be also presented. Finally, the economy of building and running the plants is studied.

Course programme

Biomass energy systems
Biomass: definition and classification. Italian rules to reduce emissions of greenhouse gases. Availability biomass at global, European and Italian. Regional availability of biomass. Chain of woody biomass, and herbaceous seeds and fruits. Dies possible in Italy. Properties of biomass. Types. Lignocellulose. Starchy. Sugar. Oilseed crops. Municipal solid waste (MSW). Manure. Liquid biofuels. Liquid biofuels. Gaseous biofuels. Processes for biomass conversion. Types and global analyzes of conversion systems. Reactor parameters and process analysis. Types of reactors. Process parameters. Analysis of the process. Biochemical conversion. Anaerobic digestion. Fermentation. Oil extraction, refining and esterification. Immisione, mixing, cooling, and monitoring. Entry systems. Mixing Systems. Harmful substances. Conditioning cold. Conditioning hot. Monitoring systems. Heat generation. Fireplaces. Boilers. Thermal power stations. Electricity generation. Turbomachines. Fuel cells. Description and analysis of two different systems of generation from biomass. Anaerobic digestion plants. Gasification plant. The cogeneration. Analysis of costs and revenues. Exercise in parallel to the electrical systems in biomass. Incentive systems and withdrawal commercial electricity delivered to the grid. Elements of capital budgeting. Impiante biomass projects.

Wind Energy

• Introduction: history of wind energy, modern wind turbines, anatomy of a wind turbine, HAWT and VAHW, power coefficient
• Airfoils and general concept of aerodynamic: general overview, aerodynamic forces and coefficients, Buckingham's theorem, Reynolds and Mach numbers, airfoils, lift and drag.
• Aerodynamic of wind turbines: one-dimensional momentum theory, Betz limit, wake rotation, blade element momentum theory, blade shape for ideal rotor, aerodynamic of VAWT.
• Wind characteristics and resources.
• Wind turbine control: introduction and motivation, overview of wind turbine control systems, active and passive control system, yaw control.
• Wind turbine design and testing: sources of loading, ultimate and fatigue loads, design loads, international standards, modern wind turbine design procedure.

Photovoltaic plants

• What is solar energy and how to take advantage of it: the source and the available power, air mass, istruments to measure irradiation, fotoelectric effect, physical structure of the photovoltaic cell, various types of cells.
• Photovoltaic cells and modules: eletrical model of the cell, output power of the cell, modules, concentrated panels, standard test conditions, interconnections of cells and modules.
• Production of electric energy: principle schematics of a photovoltaic plant, production rate of the palnt, efficiency of the plant, producibility calculation, consumed power and power injected into the grid.
• The photovoltaic inverter: priciple, inverter for off-grid plants, block schematics of grid-connected inverters, synchronization with the grid, maximum power point tracking, anti islanding, peak efficiency and European efficiency, installation issues of the inverter.
• Photovoltaic plant design: general aspects, power dimensioning and choice of the panels, verification of the shadows, photovoltaic genrator and inverter voltages, plant topology, interface with the grid, grounding, cabling, protection devices.
• Econonomy: the Italian law "V Conto Energia", payback period.

Course entry requirements

Course structure and teaching

Lectures (hours/year in lecture theatre): 68
Practical class (hours/year in lecture theatre): 0
Practicals / Workshops (hours/year in lecture theatre): 0

Suggested reading materials

Slides or lecture notes will be made available for each modules.

Testing and exams

An oral test, during which a project produced by the student will be discussed, is foreseen for each module.