The different types of energy the world uses
Oil supplies around 34% of the world’s energy needs. It is often referred to as fossil fuel because the oil is extracted from built-up organic material and fossil remains that, over time, breaks down into hydrocarbons. Oil is mostly used as transportation fuel but is also found in many other products like fertilizers, makeup, paints and fabrics.
Australia has approximately 0.3% of the world’s oil reserves, located mostly in the Carnarvon (Western Australia) and Gippsland (Victoria) basins. The 10 major countries producing oil include Saudi Arabia, Canada, Iran, Iraq, Kuwait, United Arab Emirates, Venezuela, Russia, Libya and Nigeria.
Natural gas is now the third largest global energy source and accounts for around 21% of energy consumption worldwide. Considered a fossil fuel, natural gas is formed in the earth when gases are released from decaying organisms trapped under pressure over millions of years. Natural gas can be found in oil fields, natural gas fields and coal beds and is one of the world’s cleanest, safest and most useful sources of energy.
Approximately 92% of Australia’s natural gas reserves are located in Western Australia, in the Carnarvon, Browse and Bonaparte basins. They attributed close to 2% of global gas reserves in 2008. The major sectors consuming natural gas include manufacturing, electricity generation, mining and the residential market (used for water heating, cooking and heating the home).
Coal is now one of the world’s largest sources of energy. Global coal consumption grew by 7.6% in 2010, with Asia Pacific countries accounting for 79.7% of the increase. Coal is a combustible sedimentary rock found in layers under the earth known as coal seams or coal beds.
Brown coal (or lignite) is the lowest grade of coal and is softer due to its water content. Its heating value is around one quarter of black coal. Brown coal is not always brown and actually varies in colour from yellow to dark brown. Brown coal is primarily used in electricity generation. It is burned to heat water, producing steam to run the power turbines.
China is the world’s largest consumer and producer of brown coal. Australia has approximately 8.5% of the world’s brown coal reserves.
Black coal is the highest grade of coal and includes sub-bituminous and bituminous coal, through to shiny black anthracite. Graphite is technically the hardest form of coal; however, it does not easily ignite and is used in pencils and lubricants, rather than in energy production. Not only is black coal used to generate electricity, it is extensively used in primary industries, such as cement manufacturing and steel production.
Australia has about 7% of the world’s economically recoverable black coal and ranks fifth behind USA (31%), Russia (22%), China (14%) and India (8%). Coal accounts for around three quarters of Australia’s electricity generation, with coal-fired power stations located in every mainland state.
Plutonium is a rare earth element found in trace amounts in the Earth’s crust. It is radioactive and has a silvery colour, but degrades to a dull grey, olive or yellow when it oxidises. The plutonium available today is manufactured synthetically and is found only in trace amounts within uranium deposits and is extracted by burning the uranium. Plutonium is responsible for producing over one third of the energy required to run the world’s nuclear power plants.
Approximately 11% of the world’s energy needs are supplied via nuclear energy. There are 436 nuclear power reactors operating in 31 countries. France, Japan and the United States combined account for 56.5% of nuclear generated electricity. 80% of France’s nuclear reactors provide electrical energy and the United States is the world’s largest nuclear energy producer although its electrical output is only 19%.
Nuclear energy is achieved through nuclear fission. The nuclei of atoms are split, causing energy to be released. Uranium rods are used as the fuel because the uranium nuclei are easily split when neutrons are “shot” at them. Once the uranium nucleus splits, multiple neutrons are released and they are further split into more uranium nuclei causing a chain reaction.
Australia has the second largest uranium reserves in the world but does not have any nuclear power stations.
Coal To Liquids
Coal can also be converted into a liquid fuel like diesel or gasoline through direct or indirect liquefaction. Liquid coal can become a petroleum substitute and be used in the transportation industry. It is used as alternative liquid fuels like methanol and dimethyl ether (DME); it is also used in lubricants, synthetic waxes and chemical feed stock.
South Africa has been producing liquid coal since 1955. More plants are being opened across the world and China is notably creating the two biggest liquid coal plants in the world. Large coal reserves are found in the United States, China, India, Russia, Ukraine, Germany, Poland, South Africa and Australia, with most countries starting new coal to liquid projects.
Oil shale is produced from sedimentary rocks containing kerogen which is an organic precursor to oil that release petroleum –like liquids through pyrolysis, hydrogenation or thermal dissolution. Today oil shale is used to produce oil, and be used as an energy source in both thermal and electrical power plants. Other uses include being used in cement, bricks, fertilizers, soil additives and glass.
Oil shale resources are found in many countries however there is no economical method for extracting oil from the oil shale rocks. The lack of commercial practicalities has inhibited the development of better technologies to reduce the cost of extraction.
The United States has the largest oil shale reserves and the largest producers are China, Estonia, Brazil and Australia.
Coal Seam Gas
Coal forms over millions of years, storing large quantities of a methane-rich gas and coal seam gas (CSG). CSG is often referred to as “unconventional gas” or “sweet gas” because of a lack of hydrogen sulphide, this gas is extracted from the underground coal deposits. The methane lines the inside pores of the coal and is also found in the cleats and seams; the gas is held in place by water pressure.
Coal seam gas has become a very important source of energy and especially within Australia where it supplies over 60% of the total gas market in Queensland. Gas is used to supply some of our electricity needs like running our lights, appliances and hot water.
There are large reserves of coal bed methane in Canada and the United States but Australia is the main producer of coal seam gas with 18 mining operations currently being used.