Preamble Renewable energies are beneficial for the climate and for the future, mankind and our planet. They will become unavoidable for use in the future, due to the depletion of fossil fuels. However, several economic concerns have hampered their deployment on a global scale. The question of cost and profitability has made most governments hesitate to invest large sums in it. But things are changing rapidly. The price of renewable energies is falling and more and more studies show that investing in them is beneficial for the economy and for the health of humans and their environment. The International Renewable Energy Agency has published a report which argues that the proportion of renewable energy is doubled by 2030, which will have several positive effects: the gross world product would rise by around 1.1%, the level overall well-being (health, education, income, unemployment, etc.) could rise by 3% and 14 million new jobs would be created. These important additional effects would not occur if we decided to keep the same share of green energies as that of 2015. Generally speaking, energy is just a very good fuel for the economy. It encourages production, innovation and consumption. Its demand continues to increase in growing countries. It also happens that man has reached a climax: harnessing solar and wind power has become cheaper than fossil fuels and nuclear power. This happened quickly and may come as a surprise, but the fact is that the price of these energies, especially solar energy, keeps dropping fast. The cost of a solar panel, for example, in August 2016 was worth around 30% of its price in 2010. The graph below shows the evolution of the price. In the years to come, we can expect the cost of green energies to continue to fall, while the cost of fossil fuels is likely to increase due to their scarcity. Governments and consumers will therefore save more money thanks to renewables. Amor Abbassi