We often talk about fossil fuels as a type of negative energy, polluting, harmful to the environment.
Currently, fossil fuels are the most widely used energy source in the world. It is used to generate electrical energy but above all it is also used to generate mechanical energy (cars, thermal motors, etc.).
What are fossil fuels?
Fossil fuels are those fuels that come from a process of partial decomposition of organic matter.
Some fossil fuels originate from a process of transformation of millions of years of plants and plants (oil, coal and natural gas).
These are primary energy sources since they can be obtained directly without transformation.
Formation of fossil fuels
Fossil fuels are formed by a process of partial decomposition of the organic matter. This is a process of transformation of millions of years due to the pressure and temperature of sediment layers exerted on the organic matter.
They have been caused naturally by a process of fossilization in anoxia (lack of oxygen) environment: organic matter has not been degraded by microorganisms (which can not live), but remains in the form of more complex organic molecules, solid ( coal), liquid (oil) or gas (natural gas). The energy of these molecules is that is released used as fuel.
This process of millions of years is converting fossil fuels into a source of nonrenewable energy as it consumed much faster than not generated.
The importance of fossil fuels
Fossil fuels have a high calorific power that becomes a very important source of useful energy to generate thermal energy.
The use of fossil fuels has allowed the great economic and population growth linked to the industrial revolution of the nineteenth century. At present they are critical to our economy. In 2007 the combustion of coal, oil and natural gas accounted for 86.4% of global primary energy.
Implication of fossil fuels
Fossil fuels are highly unpopular by environmental groups. Its combustion generates lots of gases. These gases becomes a one of the major sources of air pollution because that will raise to increase the greenhouse effect and hence global warming.
Today, the use of fossil fuels pose a major problem of sustainability, both for environmental reasons and economic (the planet's resources are limited and will be exhausted one day).
Types of fossil fuels
Petrol is a mineral oil consisting of hydrocarbons contained in large bags to the upper strata of the earth's crust.
This fossil fuel, once refined, gives a lot of products used as a source of energy, especially in the automotive and heat engines. These products include gasoline, diesel, fuel, etc. They can also be used as raw material for the petrochemical industry.
Coal or coal is a sedimentary rock of black color, very rich in carbon and with varying amounts of other elements, mainly hydrogen, sulfur, oxygen and nitrogen.
Most of the coal was formed during the Carboniferous period (makes 359-299000000 years).
Natural gas is a fossil energy source, as are coal or oil. It consists of a mixture of hydrocarbon molecules formed by carbon atoms and hydrogen. Its heating value varies greatly depending on their composition, but the highest are between 8,500 and 10,200 kilocalories per cubic meter of gas.
This is the cleanest fossil fuel in terms of waste and air emissions, and more efficient for producing electricity in the fuel thermal plants with a total efficiency of 50.7% compared to 25.7% of fuel , 26.1% of uranium (nuclear power plant) and 26.8% carbon.
Natural gas can be used directly without first having to convert it into electricity. This feature allows you to have a much higher efficiency of 91.2%. Storage is cheaper and easier than coal and petroleum.
It began to be used from the 60s as a preferred fuel transport except where oil continues to predominate. Furthermore, it is also used as a raw material of numerous chemicals.
Last review: November 15, 2016