Environment & Energy

Energy – Statistics Valentim M B Nunes

Unidade Departamental de Engenharias

Instituto Politécnico de Tomar, March, 2015

Energy

Thermoelectric Power Plant of Pego

Energy is a vital resource in any modern society: as the food the energy must be stored and transported in time and place is available to where it will be used.

Fossil and nuclear fuels, which store energy in the form of chemical or nuclear are the most common way of storing and transporting energy.

Engine room: boiler, turbine, condenser

Refrigeration Towers

Transmission lines (high voltage)

Renewable Energy

Castelo de Bode Dam

Renewable energy sources are of various types: wind turbines, wave energy, solar energy and hydro or mini hydro systems (dams) are some examples.

Stored water

Engine room

Transmission lines (high voltage)

3 units or groups of production, with nominal power of 392 MW.Combined cycle technology allows to achieve an energy conversion exceeding 57.5% of yield, witch compares very favorably with the 36% of a coal fired power station at Sines or Pego.

The Thermoelectric Power Plant of Ribatejo:

These modern units are quite complex, and are designed to achieve maximum thermal efficiency. But combustion of fossil fuels gives rise to solid and gaseous pollutants, such as COx, SOx, NOx, metal fumes, ashes, etc.. To remove these pollutants are required expensive equipment as "scrubbers", electrostatic precipitators, etc., which turns the price of electricity more expensive.

The Dam of Aguieira

Nuclear, Yes or not?Nuclear power plants use a steam cycle to produce mechanical energy, but the steam to power the turbine is generated by heat transfer from a hot fluid that passes through the nuclear reactor, or contact directly with reactor fuel. The main drawback of a nuclear power plant, which does not emit pollutants into the air, is the difficulty in ensuring that the immense generated radioactivity never escapes by accident.

Nuclear Power Plant of Almaraz - Spain

Over time …Agricultural societies: Solar Energy

1st Civilizations: hydropower

Growing of Europe: Canals/Dams/Mills(wind energy)

Modernity: Chemical/Mechanical energy

Industrial Revolution: Coal/vapor

XX Century : electricity, oil, nuclear

XXI Century: Thermonuclear controlled fusion?

Global Sources of Energy

1 Q = 1x1015 Btu = 1.055x1018 J = 2.9307x1011 kWh

Global consumption of electricityElectricity is a secondary form of energy generated from primary sources (fossil, nuclear, hydroelectric, geothermal and other renewable sources).

Final Energy

Global supply of energy

World fossil reserves

Fuel Reserves (Q)

Consumption (Q/y) - 1995

Growing/ year Lifetime/years

Lifetime with growing

Coal 24000 93 0.8% 258 140

Oil 9280 141 1.1% 66 50

Gas 6966 78 2.5% 90 50

* By exploring are the immense reserves of methane hydrates in the bottom of the ocean, but for which there is still no technology.

Energy consumption and production: overview

Final Energy Consumption

Energy Dependency

Production of electricity by renewable

Installed Power

International Comparison

Energy consumption in Portugal: transport, industry and domestic sector

Oil consumption

Natural Gas consumption

Electricity: Renewable vs non renewable

Evolution of prices

Price structure - 2014

Renewable

The total amount of electric power produced is corrected with the Producibility of Hydro Index (HPI) for the purposes of comparison with target set in the directive 2001/77/CE

Renewable

Problem 1.

The coal reserves are estimated at 24000 Q. What the total value in kJ? What is the lifetime of these reserves to the current consumption rate of 93 Q/year and if the consumption increase r = 0.5%, 0.8% or 1%/ year? The lifetime can be calculated via

where r is the rate of consumption growth, QT are the total reserves and Q0 is the current consumption.

1ln

0

1

Q

QrrT T

Problem 2.The table below shows the situation of the production of electrical energy from renewable sources by 2013. I) from the data estimate the production in 2020 from various sources; II) calculate these production and sources for each year and trace the scenario of evolution in Portugal.

Bibliographic references

Fay, J., Golomb, D.S., Energy and the Environment, Oxford University Press and Open University, Oxford, UK, 2004

http://www.minerva.uevora.pt/odimeteosol/energias.htm

http://www.dgge.pt