First law of thermodynamics reveals that energy can be created only by spending the available energy to convert the existing matter into more available energy. The second law informs us that the economic process is responsible for losing energy at every step. All engines waste almost 50 per cent of the energy present within the fuel whether the engine is diesel or heat.
According to net energy principle, any energy source that consumes more energy than the amount it produces is called sink. To lift a 15 kilogram of oil to five meters almost 735 joules of energy is required, where the amount of energy required for lifting increase with increasing depth. When easily accessible and concentrated reserves of oil are exploited in the beginning than more energy is need to discover and to recover more reserves of oil.
Oil produces in shale, containing high level of organic material. After its formation, the oil moves upward in spongy basin rocks of limestone or sandstone where it is trapped by a solid rock. To remove gas and oil, well are bored into these reservoirs or basins. Due to favorable conditions, tectonic plate borders have about 70 per cent of oil fields.
There is more than one stage in the recovery of oil. In first stage oil is sucked out of the basin under normal pressure of the reserve. This stage can extract about 25 per cent of the oil in the reservoir. In second stage hot water is forced into the well to push up the remaining oil where it can be collected. In case oil is still there, a third method is used in which nitrogen gas and carbon dioxide sent into the well along with steam to pump oil. The process of refinement involves the boiling of crude and by the virtue of fractional distillation removing gases. The use of oil is not only limited to the energy formation, it also involves in providing basic product for several industrial chemicals like plastic.
To convert oil into electricity three technologies are implied: Conventional Steam, Combustion Turbines and Combined Cycle Technology. In Conventional Steam method oil is simply burn to generate heat which converts water into steam. The steam later on runs turbines to generate electricity. Combustion Turbine burns oil under high pressure which results into the generation of hot gases that are used to directly run the turbine to produce electricity. In the third method oil is burnt in the Combustion Turbine to generate gases that spin the turbine. These gases are then projected into the chamber where water is kept. On turning water into steam, the steam is used to make electricity. So the method employs two steps to make the most of oil combustion.
Middle east traps about 50 per cent of the total oil of the world where remaining reserves are in North America. Most of these reserves are already used while the number of discovering new reservoirs is very slow. It is estimated that the remaining oil will be exploited in another 30 years if new reserves are not discovered.
In fossil fuels, oil is preferred over coal because it is environment friendly and emit about 50 per cent less sulfur dioxide (SO2).it can however trigger several environmental issues. Although less than coal, but the consumption of oil involves the discharge of a variety of pollutants like carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxide (NO) and sulfur dioxide (SO2). These pollutants create fog, and contribute in green house effect. The green house effect is responsible for continually raising the temperature of earth which will one day make this planet unfit for habitation. Many significant oil reserves are under sea and their drilling offer several threats of accidents in which oil can spill into the ocean to damage the marine population. Transportation of oil often leads to its spilling into water. In 2002, a major oil slip happened in Spain. Those oil reservoirs that situates in wilderness offer trouble to the habitants of forest by their machinery.
Oil is an abundant source of non-renewable energy which is preferred due to its liquid form. The heating value of oil is very high. The extraction of oil can be carried on by using old technologies. Oil drilling is threatening for the environment where the reserves of oil are limited and once exploited will be useless.
A fossil fuel takes millions of year before it comes into its usable form. It is pertinent to note that the consumption of oil is 65 billion barrels per day in the world. The consumption will increase up to 99 barrels per day by 2015. Despite of whatever petroleum geologist claim one thing is for sure that human beings have come across new sources of energy to keep up their day to day life. One day all the oil reserves will be exploited, till than if we will not be able to discover new oil beds then we will be surely king of new resources of energy