31410 - Energetics

Course contents

Definition of measurement units for energy consumption: toe, tec, oil barrel. Brief Italian history of energy. Energy consumption in the world and in Italy. Analysis of the Enea Report.

Recall of thermodynamics: basic definitions, first law, energy, second law, impossibility of perpetual motion of the second type.

Fundamental relationship and Gibbs equation for the open system. Definition of chemical potentials. Chemical potential of a perfect gas. Euler's equation. Stoichiometric coefficients and chemical equilibrium condition.

Adiabatic availability function. Keenan's availability function. Flow availability.  Exergy. Flow exergy. Exergy balance equation for a closed  system and for an open system.

Definition of exergetic efficiency of a motor cycle, a refrigeration cycle and a heat pump. Definition of the exergetic efficiency of the pump, compressor, boiler, heat exchanger. Exercises.

Presentation of the electricity market. Structure of the electric bill. Presentation of the natural gas market. White and green certificates. Role of Energy Manager and Esperto in Gestione dell'Energia.

Elements of economic analysis. Definition of simple pay back, discounted pay back, net present value, internal rate of return. Energy, exergetic, environmental and economic analysis applied to some examples, for the replacement of a boiler and a water heater.

Solar energy. Recalls of thermal radiation and general introduction to solar energy.

Solar energy. Analysis of low temperature systems. Flat solar collectors and their efficiency. Energy and economic comparison of a natural gas boiler and a solar collector.

Biomass energy. Classification of biomass and plants. Thermochemical process. Biochemical processes. Biogas production. Production of biodisels and oils.

Wind energy. Dynamics of air masses: baric gradient and Coriolis forces. Geostrophic wind. Centrifugal force. Cyclones and anticyclones. Frictional force in the field of parallel plane isobars. Vertical temperature distribution. Pressure field in the troposphere. Air density field in the troposphere. Characterization of the wind site: probability density of Weibull for wind speed. Calculation of average velocity and variance according to the Weibull probability distribution. Calculation of the median speed. Calculation of K and with the analytical method, the method of experimental correlations, the method of minimum square waste, the method of least squares with respect to the cumulative frequency. Calculation of wind power. Power coefficient. Determination of maximum transferable power. Betz limit. Power curve of an aerogenerator. Examples of wind machines. Economic evaluation of the unit cost of electricity per kWh.

 

 

Readings/Bibliography

readings given by the teacher

Teaching methods

Lectures and exercises in classroom.

Assessment methods

The assessment aimed to verify knowledge and skills acquired by the student in relation to all the contents illustrated above. The assessment consists of a written exam, which includes a theory question and an exercise. During the examination, the use of books or bibliography/readings is not allowed. An oral examination can be requested by he student, after a positive mark in the written one.

Office hours

See the website of Eugenia Rossi di Schio