Although there are numerous different sources of energy available, more than three-quarters of the energy utilized in developed countries comes from oil, gas and coal. These fuels are loaded in carbon and hydrogen. They burn in air to form CO2 and water, a process that releases heat energy.
Fossil fuels were formed millions of years back from the remains of plants and animals. There’s a limited supply of these fuels and now they are being used up at a far faster rate than they are being formed. Soon they’re going to run out.
Oil is created under the sea from the remains of marine life. The oil formation process is similar to that of coal. The remains become buried under layers of sediment, and the ensuing high pressure and temperature make them turn into a black liquid with a high carbon content. Frequently gas forms in the same place as the oil. The liquid oil moves towards the surface and becomes besieged under layers of impermeable rock. The pressure builds up as more liquid moves upwards.
Though oil is created under the sea, plenty of the world’s oil fields are located on land. This is a consequence of changes in sea levels and movements in the Earth that have ‘uplifted ‘ rocks, making them lie above water.
The oil and gas is reached by drilling wells, frequently several kilometres long, thru the overlying rock. When the drill breaks through the rock above the oil, pressure is released, and the oil spurts out of the well. To stop this from taking place, engineers place special valves at the very top of the well. When there isn’t really enough pressure to push oil to the surface, water or gas can be pumped into the well to push the oil out. The crude oil that comes out of the ground has to be taken to refineries to be processed before it can be utiliized.
Oil companies are now searching for new oil and gas fields in some of the planet’s most inhospitable places, such as the frozen ice fields of Siberia and Alaska and the Arctic Ocean. Once all the oil fields are exhausted, the energy companies may turn their attention to oil shales. These are rocks that have oil inside them. However , removing oil from rock is terribly costly and produces a large amount of waste.
It is continuing to become clear that using green renewable power sources, for example solar power, must become a priority before oil runs out and the environment is irrepairable.
Sarah Green is an environmental campaigner, activist, and strong supporter of home made energy. In her spare time, she reports on DIY green energy plans and kits.