Thermal Energy Storage

3 outubro 2019, 16:00 • Joao Manuel Nunes Alvarinhas Fareleira

Storage of sensible heat; storage materials; some examples in everyday life; traditional examples in industry of sensible energy storage systems: regenerators and systems for heat transfer between fluids and granular materials in beds, either fixed or moving. Heat transfer between a storage material and a heat transfer fluid (HTF). Latent heat storage. Phase change materials (PCM): advantages and difficulties associated to PCMs when compared to sensible heat storage materials. Discussion of the advantage of a small temperature variation of the material on energy charge and discharge. Analysis of a passive latent heat storage system, consisting of the discharge of a fixed bed of PCM particles, by a heat transfer fluid. Mention of Trombe walls as examples of sensible or latent heat storage from solar energy. Phase change materials (PCM): Advantages; difficulties in their use and solutions to improve their perfomance; general practical requirements for selection of PCMs.

Thermal Energy Storage

27 setembro 2019, 14:00 • Joao Manuel Nunes Alvarinhas Fareleira

Introduction to Thermal Energy Storage; sensible and latent heat storage; short-term and long-term thermal energy storage. Some basic concepts of Thermodynamics and Heat Transfer important for thermal energy storage. 0th and first laws of Thermodynamics. Sensible and latent internal energy. Heat transfer modes. Concept of thermal resistance to conduction and to convection. Effect of the thermal conductivity and of the heat transfer convection coefficient on the resistance. Association of resistances in steady-state conduction problems with convection at the boundaries. Resistance to the steady-state heat transfer rate between two fluids across a wall (slab). Brief notions of heat transfer by radiation; "Green house effect". Effect of the heat transfer area on the heat transfer rate. Discussion and resolution of an exercise on the effect of the size of the capsules containing energy storage materials and the area available to heat transfer by convection. Effect of temperature on the thermal conductivity of gases, liquids and solids. Storage of sensible heat; storage materials; some examples in everyday life; traditional examples in industry of sensible energy storage systems. Storage of sensible energy in buildings from solar energy: Trombe walls; characterisation; physical mechanisms.

This class was given by Prof. Maria Rosinda Ismael.

Why Energy Storage? Reasons to store energy throughout time

26 setembro 2019, 16:00 • Marta Ramilo Abrantes

Why Energy Storage? Reasons to store energy throughout time

Energy consumption by source

Wood

Coal

Petroleum

Natural Gas

Hydropower

Nuclear Electric Power

Other Renewable

The contribution of storage to the Energy Trilemma

Technologies for thermal and electrical storage (applications,maturity and current projects) 

World Energy Overview

20 setembro 2019, 14:00 • Marta Ramilo Abrantes

Definition of Energy

Available Energy Sources

Primary World Suply

World Consumption

Electricity Generation - diferences throughout the world

CO2 emissions

Challenges for the future of Energy

Future scenarios