c organism like bacteria, we find that energy is needed to be in motion. So how did everything gets the energy?
If we take a look on the thermodynamics which deals with the study of energy, we found 1st law of thermodynamics which states “Energy can neither be created nor destroyed but it can be transferred from one form to another form.” This shows that everything in motion is somehow taking in energy as fuel and converting it into its desired work. So energy can be classified on the basis of its sources from which it is converted to another form. One of the type of energy is obtained from those sources which are extinct able and will be vanished in future. Examples include fossil fuel energy i.e. from petrol, Natural gas or Coal. Second type is of our interest, which is the renewable or green energy which is simply energy obtained from sources that do not have a finite end or those that can be recycled. We can call them natural sources e.g. Solar, Wind and water. These are the examples that we consider most of the time when we hear “renewable energy” but these are not the only ones.
We use energy in everything and every day of our life. Our electronic devices need electric power, our streetlights need the same thing for lightening, and our vehicles require gasoline or diesel. We fuel our homes with domestic oil, propane or electricity from a natural or local grid for lightening, heating and for powering our devices. The place we work use computers, phone networks, security systems and servers, as do our shopping malls, parking lots, sports stadiums, cars, airplanes and so on. All of these things require power from fuel.
Total World Energy Consumption by Source
If we take a look on the overall energy consumption of the world we came to know that are at the top with 80.6% consumption and renewable energy is at the second 16.7%. But according to a report by International energy agency, the increase of amount of electricity produced form renewable sources increased and they predict that that figure will hit 26% by 2020. More long term forecast models predict that use will triple between 2012 and 2040, with a greater amount should the planet hit 2 degree of warming. Those increasing trends shows that people are now more concerned about green energy sources.
The first reason that why those trends are increasing and should be increased, for the utilization of green energy is that the fossil fuels are limited. As the world’s population is increasing, our rate of fossil fuel consumption in also increasing. Geologists and others whose job it is to locate and access these fossil fuels inside the earth are finding it more and more challenging to locate and extract new oil sources. Many argue that fossil fuels will eventually run out so we should prepare our self and promote the alternate source of energy extraction.
Second and the most serious cause is the carbon emissions and the climate changes that we have seen in the last decades. Most continents have recorded record high temperatures in summer and record low temperatures in winter, increased frequency of typhoons and hurricanes, record dry spells, drought and flooding.
Next reason is the economic stability as renewable energy offers a constant and sustained supply and energy prices are low and likely to remain stable and hence economy will be stable as a result. Most of the states are now switched to green energy sources because of cheaper energy production rates e.g. Idaho produces a large amount of energy from geothermal sources. Another example is Texas where energy produced from wind power is noticeably cheaper for the state’s citizen.
Environmental damage is another reason to consider for the green energy. As fossil fuel supply gets harder to acquire, and prospectors search for new pockets of oil and have to drill longer and deeper to acquire it, there has been conflict between environmental groups and industry  and between governments and both groups  when local wildlife and environmentally sensitive areas are in danger. Oil, gas and coal drilling and mining have high levels of pollution that are pumped into local environments and the wider atmosphere, so while protestors attempt to prevent the building of pipelines or new prospecting in virgin areas and wilderness, it is as much about public health as it is about conservation.
The concept of peak oil in the 1950s began a new drive towards renewable energy sources. Solar, Hydro and other were seized upon by both environmentalists and industrialists. They were both equally concerned about the exponential growth in human population, in oil consumption, and realized that it is a finite resource and will run out  regardless of the size of supply today. A growing environmental movement, the development of environmental sciences and a push against pollution meant that more than ever before, renewable energy became not just a scientific innovation for the future, but a necessity.