- The question “What is energy?” is difficult to answer in a simple, intuitive way, although energy can be rigorously defined in theoretical physics.
- In the words of Richard Phillips Feynman, “It is important to realize that in physics today, we have no knowledge what energy is. We do not have a picture that energy comes in little blobs of a definite amount.
- However, energy is the capacity of a physical system to do the work. It comes in many forms, such as kinetic energy, potential energy and many others. It is denoted by E and measured in N-m.
- Energy resources are indispensable for any companionship, be it one dependent on subsistence farming or an industrialized area. A resource is a source or supply from which benefit is realized.
- There are many different sources of energy, some well-known such as coal or petroleum, other less so, such as tides or the heat inside the earth.
- Understanding energy resources involve considering all types of energy source from various scientific and technological perspectives, with a focus on the uses, limitations and implications of using energy that is available to man.
1.2 CLASSIFICATION OF ENERGY RESOURCES
Energy sources can be classified as follows:
Based on traditional use
Conventional: Resources which are being traditionally utilized for many decades and were in common need around the oil crisis of 1973, are named conventional energy resources. E.g.: fossil fuels, nuclear and hydro resources.
Non-conventional: Resources which are taken into account for a large scale use after the oil crisis of 1973, are named non-conventional energy resources. E.g.: Solar, wind, biomass, etc.
Based on availability
Non-renewable: Resources which are limited and do not get replenished after their consumption are named non-renewable. E.g.: fossil fuels, nuclear resources, etc.
Renewable: Resources which are renewed by nature again and again and their stock is not affected by the rate of their consumption are named renewable. E.g.: Solar, wind, biomass, hydro, geothermal, tidal, etc.