HKNIC - Non - renewable energy
tc


Non - renewable energy
There are several available energy sources for producing electricity, which may be classified as non-renewable and renewable.

Non-renewable energy
Non-renewable energy sources include fossil fuels and nuclear energy. Fossil fuels such as coal and oil are all carbon based. They take millions of years to create and are now being used up far more quickly than they are being replenished. Materials that can be used for nuclear power, such as uranium, were created even earlier during the formation of galaxies. None of these fuels is renewable, even though they are abundant. Their abundance allows them to be consumed on a large scale. A power generating unit using fossil fuel or nuclear energy has a typical capacity ranging from several hundred megawatts (MW) to over 1,000 MW. A dozen or so of these units are enough to supply the electricity needs of Hong Kong.
Coal is the fossillised remains of vegetation that formed typically several hundred million years ago when they were covered by overlaying layers of sediment. The amount of carbon in the coal increases with time under the of weight of the rock formation pressing down from above and the heat rising up from the core of the earth. Lignite or "brown coal" is a low-grade fuel between peat and coal, having typically less than 40% carbon content. Bituminous coal or "soft coal" is a dense black substance formed after further compaction, with a typical carbon content of 65%. Anthracite or "hard coal" is black and shiny, with a carbon content over 95%.
Petroleum is a mixture of several liquid hydrocarbon substances formed from the oil of ancient microscopic marine plant and animal matters that have accumulated under sediments in porous rock formations. It is sometimes simply known as “crude oil”, while oil is an all-encompassing name for petroleum and its refined products such as gasoline and kerosene.
Natural gas is a combustible hydrocarbon gas often formed together with petroleum and sharing the same porous rock formation. It mainly comprises the gas methane.
Nuclear energy is derived from the breaking up (fission) or merging (fusion) of the atomic nuclei of matter. Uranium is a metallic mineral capable of fission and is the most commonly used fuel in nuclear power stations.