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NEWS: IN 2016/17 LECTURES WILL BE ALSO AVAILABLE IN VIDEO
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The course is devoted to present both the Photovoltaic and Wind power systems, within the electric Renewable Energy sources, and the methods to correctly design the main components, to evaluate the energy production with the economic analysis of investment.

At the end of the course students should know the main technologies about the photovoltaic plants and wind turbines, and should be able to correctly design the main components of these power systems.

Basic knowledge about Physics, Electric circuits and Mechanics.

PHOTOVOLTAIC POWER SYSTEMS
Solar energy characterization: background. Models of solar radiation for average and clear sky: use of "ad hoc" software.Structure of the semiconductors: energy bands; doping; p-n junction and electric field; electron – hole pairs; losses in the energy conversion. Spectral response and efficiency of the main technologies: single, multi-crystalline and amorphous silicon, Cadmium Telluride, Copper-Indium- Diselenide. Surface covering per installed kilowatt. Equivalent circuit of the solar cell, I-V and P-V characteristics at variable irradiance. Focus on an application problem: series/parallel connection of cells; I-V curve mismatch and shading effect; hot spots and breakdown; bypass and blocking diodes. Datasheets of the commercial PV modules, thermal coefficients of the electrical quantities. Calculation of the electrical parameters of the PV modules in ambient conditions different from the STC by datasheet of the manufacturers.
DC-AC converters for the grid connection: Maximum Power Point Tracking (MPPT); active/reactive power control; interface protections; protections against over-current and direct/indirect contacts. Sizing of the components in a PV plant. Optimal coupling PV array/inverter: checking of power/voltage/current. Plant schemes; costs of installed power and produced energy. Conventional calculation of energy production: loss sources in the productivity, technical/economic analysis by the Net Present Value (NPV). Automatic Data Acquisition System, experimental results on operating PV plants, typical testing procedure. Pros and cons of Photovoltaics. Calculation of the energy production in a PV system. Energy balance on yearly basis in grid connected PV systems

WIND ENERGY INSTALLATIONS
Characterization of the wind: speed and direction; power density; surface roughness; statistic distributions. Structure of a wind turbine: blades, hub, gearbox, electric generator, tower. Operating Principle of a wind turbine: lift and drag in a blade; pitch and yaw regulations; adjustment toward stall/feather. Equivalent circuits of induction and synchronous machines and power curve vs. wind speed. A solution for variable speed wind turbines: the doubly-fed induction generator. Calculation of energy production for a wind turbine. Wind park effect in a wind farm.
Wind farms: interference among wind turbines, wind park effect. Environmental impact of wind turbines: noise. Power size, diffusion of wind installations in the world. Schemes, cost of installation and energy. Advantages and drawbacks.

The course covers two main topics: photovoltaic and wind power systems.
Before starting these two main topics, the basic concepts of electrical circuit theory are recalled in the first two weeks (9 h for both DC and AC circuits).
The photovoltaic technology is explained during the following eight weeks: lectures cover 24 h, while practical exercises and laboratories of power electronics (diode, solar cell, transistor as a power switch, and single-phase inverter) cover 12 h.
The last four weeks are dedicated to study the wind turbine technologies, both fixed-speed one and variable-speed one: lectures cover 10 h and practical exercises cover 5 h.

Documents provided in the web portal,
M. Patel, Wind and Solar Power Systems, 2006, CRC Press, USA.

Written exam with theoretical question and numerical exercise. Oral exam only above 25/30.