Renewable energy is the energy that is collected from renewable resources, which are naturally replenished on a human scale, such as sunlight, wind, rain, tides, waves and geothermal heat. Renewable energy often provides energy in four important areas: electricity generation, heating and cooling of air and water, transportation and rural (off-grid) energy services. Based on the 2016 REN21 report, renewable energy contributed 19.2% to the total energy consumption of human beings and 23.7% to its electricity generation in 2014 and 2015, respectively. This energy consumption is divided into 8.9% from traditional biomass, 4.2% as thermal energy (modern biomass, geothermal and solar), 3.9% for hydroelectric electricity and 2.2% for energy Wind, solar, geothermal and biomass. Global investments in renewable technologies amounted to more than US $ 286 billion in 2015, with countries such as China and the United States investing heavily in wind, hydroelectric, solar and biofuels. Globally, it is estimated that 7.7 million jobs are associated with the renewable energy industries, with solar PV being the largest renewable employer. As of 2015 worldwide, more than half of all new installed electrical capacity was renewable.
Renewable energy resources exist in broad geographic areas, in contrast to other energy sources, which are concentrated in a limited number of countries. The rapid deployment of renewable energy and energy efficiency is leading to significant energy security, mitigation of climate change and economic benefits. The results of a recent literature review concluded that as greenhouse gas emitters began to be responsible for damage resulting from GHG emissions, the high liability mitigation value would provide powerful incentives For the deployment of renewable energy technologies. In international public opinion polls there is strong support for the promotion of renewable sources such as solar energy and wind energy. At the national level, at least 30 nations around the world already have renewable energy providing more than 20 percent of the energy supply. National renewable energy markets are expected to continue to grow strongly in the next decade and beyond. Some places and at least two countries, Iceland and Norway generate all their electricity with renewable energy already, and many other countries have the goal of reaching 100% renewable energy in the future. For example, in Denmark the government decided to switch the total energy supply (electricity, mobility and heating / cooling) to 100% renewable energy by 2050.
While many renewable energy projects are large-scale, renewable technologies also adapt to rural and remote areas and to developing countries, where energy is often crucial to human development. UN Secretary-General Ban Ki-moon has said that renewable energy has the potential to elevate the poorest countries to new levels of prosperity. Since most renewable energies provide electricity, the deployment of renewable energy is often applied in conjunction with additional electrification, which has several benefits: Electricity can be converted to heat (where it is necessary to generate higher temperatures than fuels Fossils), can become mechanical energy with high efficiency And is clean at the point of consumption. In addition, electrification with renewable energy is much more efficient and therefore leads to a significant reduction in primary energy needs, since most renewable energies do not have a high-loss steam cycle (fossil energy plants Usually have losses of 40 to 65%.