2.2 ENERGY SOURCES NON-RENEWABLE ENERGY SOURCES Energy is essential to life and all living organisms. Energy choices and decisions impact the Earth’s natural systems, so it is essential that we choose between non-renewable and renewable energy sources carefully. The true cost of energy is more than just money; there are important economic, political and social factors and consequences to consider as well. Fossil fuels cannot naturally replenish themselves, are limited in supply and cannot be used sustainably. There are three major types of non-renewable sources: oil, natural gas and coal, which are collectively called . Fossil fuels were formed within the Earth from dead plants and animals 400 million years ago, hence the name "fossil fuels". They are found in underground layers of rock and sediment. Pressure and heat worked together to transform the plant and animal remains into crude oil (also known as petroleum), coal, and natural gas. Non-renewable energy sources fossil fuels Oil is a liquid fuel which can be refined to produce products such as petrol, diesel and various other forms of petrochemicals . The most common method of extraction is and the global production is at the rate of several million a day. Crude oil 1 drilling barrels DO What kind of products does the petrochemical industry produce from refining crude oil? 1 Natural gas consists mostly of methane and is found near oil deposits below the Earth's surface. Natural gas can be pumped out through the same used for extracting crude oil. It is burned to produce electricity, to cook and to heat buildings. It is also used as fuel for natural gas vehicles. Natural gas 1 wells MORE Russia is home to the world's largest natural gas reserves, around 19% of the world’s total reserves, in Siberia. 1 Coal is extracted from the Earth by . When burned, it releases greenhouse gases. About two-thirds of the coal mined is burned in power stations to produce electricity. Coal mining Impact on the environment Burning fossil fuels results in the production of carbon dioxide and other greenhouse gases which cause global warming. The risk of and is very high and when such accidents happen they cause terrible damage to the environment too. oil spills gas leaks Economic and social aspects While almost every country in the world depends on oil, only a few countries produce it. The six top five oil-producing countries are: Saudi Arabia, Russia, the United States, Iran and China. At the current rate of consumption, it is estimated that oil reserves will run out within the next century. This is considered the which makes us move from oil and utilise renewable resources. turning point