Despite the absence of a clear and binding set of targets taking into account every State's abilities, and although the Paris Agreement doesn't directly indicate the important role of renewable energy, the answer cannot be hide anymore. As explained in the book, the necessary and at the same time optimistic and promising method is the establishment of a legally binding framework for the obligatory increase of renewable energy share in every State. If we want a future that temperature remains below of a 2o C increase, and to achieve sustainable development it means that renewable energy sources must have a legal obligatory implementation system, which will be the base for a promising adjustment. Humanity has taken steps to realization of the Climate Change issue, and it's time to realize that the solution already exists and needs a necessary push at the present, in order to have a sustainable future.