In simple terms Renewable Energy, as its name implies, is energy that is renewable—it is naturally replenished and is the energy that is derived from nature itself like water, sunlight, wind etc.
Most of the energy used before the start of the Industrial Revolution was renewable energy. The beginning of the Industrial Revolution led to an increase in the demand for coal, and as a result, it replaced most of the “bio mass” used by humanity. With the discovery of oil, renewable energy was being rapidly replaced by non-renewable energy, as they were able to generate more energy at a lower cost.
However, even during the Industrial Revolution it was recognized that these energy sources were finite. Scientist started developing
and theorizing concepts of solar energy as early as the 1870s. With the invention of a solar-powered engine by French mathematician, August Mouchet, whose method of creating solar energy is used even today, the interest in solar energy grew in the following decades. The Scientific American, an influential science magazine, published over 50 articles on solar energy between 1880 and 1914.
Since early in the process of coal and oil mining, it was apparent that there would be a peak and a time when these resources would run out. In the 1950s the concept of peak oil and concern about the exponential growth in human population and, subsequent increase in oil consumption began a drive towards sustainable energy. The development in environmental sciences, growing environmental movements and push against pollution highlighted the need for a change in the way we produce energy. Technologies that used renewable sources is central to this energy transition.
In a report by International Energy Agency, the amount of energy produced from renewable sources increased from 13% in 2012 to 22% the following year. It was predicted that, by 2020, this figure would hit 26%.
The world is doing what it can in order to reduce GHG emission, limit global average temperature change and move towards sustainable development. The Paris Agreement, 2015 (or COP21) was a step towards an increased commitment to renewable sources of energy.