school energy&environment

Hydrocarbons and climate change

Fossil fuels (oil, gas and coal) are, today, the most utilized sources worldwide for the production of energy. They account for over 80% of the energy consumption of the planet. Their combustion, however, involves the emission of large amounts of carbon dioxide (CO₂), whose increasing concentration in the atmosphere is considered the principal cause of climate change.
The need to satisfy the growing demand of energy on a global scale  and in particular the demand of the emerging countries, is balanced by the need to contrast the risks of an impact on the climate deriving from the increase in CO₂. In order to decrease CO₂ emissions, there are various ways. The first, which can be carried out in the short term and which can be implemented immediately is  energy efficiency, in other words use of technologies that enable the consumption of less energy for an equal amount of services offered. Another possible solution is to use the renewable energies, which at present still have a modest role. In fact biomasses and assimilated materials (wood  products, waste, etc.) account for 10% of the total energy requirement, hydroelectric energy accounts for 2% while the other renewable energy sources (solar, wind, geothermal, etc.) even though rapidly growing, satisfy only 1% of the world demand of energy. Also nuclear energy is a possible solution in order to contrast climate change as no CO₂ emissions are produced. Currently nuclear energy accounts for 6% of the world demand of energy, a share that is still not competitive when compared to the fossil fuels.
Comparing hydrocarbons  
Among the fossil fuels,  methane currently seems to be the one that will have a growing utilization in the near future, due to the fact it is relatively abundant and due to the fact that it is relatively “clean”. Its molecule consists of 4 atoms of hydrogen and one of carbon  (CH₄). When it burns this is the hydrocarbon that produces the smallest amount of carbon and for this reason it is less harmful for the environment. It produces CO₂ emissions that are 25% less than petrol, 16% less than liquid propane gas (LPG), 30% less than diesel oil and 70% less than coal. Its capacity to form ozone is 80% less than petrol, 50% less than diesel oil and LPG. Furthermore,  emissions from combustion do not contain carbon deposits, benzene and particulate matter PM10, unlike benzene and diesel oil. Among all the fossil fuels, methane is surely the most “ecological”. It is estimated that its use shall increase greatly in the near future.