The world of energy

18 May 2018

The world lives on energy. Every instant of life requires energy- whether to breathe or to perform vital biological functions for sustaining life or to perform external activities that build civilisations. The prehistoric man used manual effort or manual energy to perform tasks for sustaining life- such as hunting or food gathering. Somewhere he discovered fire and learnt to harness it to provide light and energy for secondary activities such as providing warmth or cooking food. Simultaneously he also discovered primitive tools for hunting, digging etc. Till the medieval ages, man used biofuels such as firewood for most of his energy needs.

The Industrial revolution revolutionised energy use by harnessing the power from primary fuels to utilise it for different end use such as motive power, heat pumps and electricity generation. European powers ruled the world as they utilised the primary energy sources many times more efficiently for industry, warfare and transportation. The industrial revolution was speeded up by the increased use of energy- dense fossil fuels such as coal, oil and gas. Today fossil fuels form a major portion of the world’s energy use and the world’s geopolitics is dictated by the race to control fossil fuel production sites. Especially, mineral oil is considered to be the most useful form of primary energy- due to its high energy density and ease of handling, transportation and storage. Almost all of the modern world’s transportation- be it land, sea or air is fuelled by mineral oil- petrol or diesel. Another major development was that of the electricity grid that brought useful energy into people’s homes and which replaced all kinds of manual tasks earlier performed by human effort. It is also a very clean form of energy without harmful fumes or residues that are formed by the use of firewood. A bulk of world’s electricity is produced from coal and natural gas.

Among fossil fuels, gas is the cleanest form of energy and therefore very useful for domestic cooking use than the use of firewood.  

Human being also harnessed the potential energy of stored water on a height to convert it into kinetic energy of its flow to generate electricity. This hydro- power generates about 17% of world’s electricity today.

The discovery of semiconductors led to a revolution and man started using electrical impulses to do intellectual activities such as calculation- a replica of human brain function. Today, the world of electronics and telecommunication dominates every aspect of human civilisation. This has added to the requirement of electrical energy many times over the industrial age.

The second world war saw the development of nuclear power- the most energy dense of all power sources and also the cleanest. The energy from the atom can power the entire world many times over with minimal Green house gas emissions.

In the recent past, human being has developed alternate sources of power such as power from the flow of wind, tides and waves. Man has also harnessed the power from sunlight to generate electricity – utilsing the Photovoltaic effect- which has shown great promise as a major energy source for the future.

Recently, a technology to extract mineral oil called ‘ fracking’ is being developed in the United States which is said to provide access to such large deposits of mineral oil that the United States need not depend on other countries area for its oil requirement.

Scientists are also on the constant look out to increase energy efficiency in generation and usage.

Needless to say, quest of human beings is to gain energy security- availability of useful form of energy and also the primary energy required to produce the useful energy.