33964 - Environmental Impact of Energy Systems M

Learning outcomes

Objective of the course is the study of the environmental impact from energy system

Course contents

Module 1

 

Introduction

 

Environmental impact of power station cooling systems.

Water/air Condensing systems. Cooling tower. The plume. Water consumption. Concentration cycles.

PM emitted by cooling towers, Drift Rate. EPA and Reisman & Frisbie PM emission models.

 

Pollutants formation mechanisms. (NOx, SOx, PM, CO and HC). Effects of CO, HC, NOx, SOx, O3, PM in the atmosphere.

 

Combustion.

Definitions, ignition, flammability limits, rich and lean mixtures. Flame temperature.

Classification of combustion process: definition of premixed and non-premixed combustion, flame speed.

 

Gas turbine combustors.

Combustor pressure drop. Combustor architectures.

Methods for emission reduction in gas turbine combustors. NOx reduction with water/steam injection.

Design of low emission combustors: rich-lean and lean-lean combustors, Dry Low NOx combustors.

Post-combustion emission reduction techniques: SCR systems.

 

Steam power plants.

USC and conventional plants.

Coal fired power plants. Pulverized coal burners and emissions.

Flue gas abatement systems: Wet Scrubber (layout and working principle), Dry Scrubber (layout and working principle), electrostatic precipitator (layout and working principle), fabric filters (layout and working principle), cyclone, SNCR. Disposition of abatement systems in the flue gas line.

Pulverized coal power plants. Plant layout. fuel preparation, pulverized coal combustors.

 

Module 2

Chillers

Chiller cycles classification, single compression chillers (layout, p,h diagram, EER), double compression chillers (layout, p,h diagram, EER), working fluids and environmental impact (ozone depletion and greenhouse gases emissions, ODP, GWP, TEWI).

Geothermal energy

Main characteristics and suitable sites: hydrothermal, dry hot stones, molten rocks, pressurized geothermal systems for ground heat exploitation. Geothermal systems typologies: Steam water wells (ambient pressure discharge and condenser configurations), Dominant water wells (flash and binary cycles). Layout, thermodynamic diagrams, performance and environmental impact. Integrated systems geothermal energy – fossil fuels.

Geothermal heat pumps: operating principle (layout, components, thermodynamic diagram of the cycle). Ground coupled heat pumps (GCHPs), ground water heat pumps (GWHPs) and surface water heat pumps (SWHPs): layout, performance and applications.

Wind energy

Main characteristics and suitable sites; on-shore, off-shore plants, turbines typologies, wind power, power density, coefficient of power, Betz-Lancaster limit. Design criticisms, wind conditions analysis for the installation site. Environmental impact and focus on off-shore visual impact.

Solar energy

Main characteristics, irradiation outside and inside of the atmosphere, ground irradiation, energy conversion potentiality. Photovoltaic solar panels: operating principle and conversion efficiency, I-V curves, parallel and series connection, stand-alone and grid-connected plant configurations. Thermal solar panels: operating principle, typologies (evacuated tubes, plate), maximum temperature evaluation of a solar collector. Concentrated solar power.

Storage technologies

Renewable energy sources penetration and problems. Electrical energy storage (classification, characteristics, advantages and criticisms): pumped hydro storage, CAES, batteries, flywheel, hydrogen and syngas production, capacitors and super-conductors. Thermal energy storage (classification, characteristics, advantages and criticisms): sensible, latent and thermos-chemical heat storage. Focus on power to gas systems for synthetic natural gas production.

Hydraulic energy

Main characteristics and classification: hydroelectric reservoir plants and flow water hydro-plants, classification based on available head and achievable power. Pelton turbines: scheme and operating principle, velocity triangles, distributor outlet velocity and flow rate evaluation, Euler work, off-design and characteristic curves. Francis turbines: scheme and operating principle, velocity triangles, balance of the axial forces on the turbine rotor, Euler work, influence of the discharge duct in a Francis turbine and performance curve. Kaplan turbines: scheme and operating principle, velocity triangles from hub to tip, performance curve.

 

Readings/Bibliography

"Sistemi Energetici: Complementi" M. Bianchi, F. Melino, A. Peretto – Pitagora Editore

"Sistemi Energetici: Impatto Ambientale" M. Bianchi, A. De Pascale, A. Gambarotta, A. Peretto – Pitagora Editore

Teaching methods

The course consists of 6 credits (CFU) in a single module.

The module provides some lessons presenting numerical examples.

Assessment methods

The examination at the end of the course aims to assess the achievement of learning objectives, verifying the knowledge that the students have acquired about design aspects, structural, functional and management about the environmental impact from energy system
The final grade is defined by a single oral exam, testing the student's knowledge in all topics covered in the 6 CFU

Teaching tools

Teaching materials: teaching material presented in class will be made available to the student in electronic format via internet.

Office hours

See the website of Andrea De Pascale

See the website of Maria Alessandra Ancona