The climate change represents today the main topic in the international politics. The Paris climate change agreement will survive Donald Trump’s decision to pull out. It was not a surprise, but it is a shock to the deal so carefully woven together after years of effort only 18 months ago. There will not be immediate consequences for the planet, but the time available for effective action is already perilously short; even the threat of a backward step by the world’s second-largest emitter of greenhouse gases could carry serious consequences. The negotiators at COP21 in Paris took a decision to reshape the energy sector considering the unstainable trends in our actual scenario. Paris represent the opportunity to put forward a different vision of our energy future where the needs of the energy must avoid dangerously overheating of planet and secure an affordable future to the next generations. The agreement looked at the changes that would be required in the energy sector to limit the concentration of greenhouse gases in the atmosphere to around 450 parts per million (ppm)– the maximum estimated level that can be allowed to keep the global temperature rise to less than 2°C. The transition is already started and sees the main contributor to the emission of CO2 such coil and oil demand declines in the outlook and the other source of energy like gas and renewable energy have a growth. Naturally the politics has a great weight in this transition, meet the needs of growth of the country and secure the reduction of the total emission of greenhouse gas. One way to reduce the total emission is the energy efficiency. The efficiency needs to be at the heart of any strategy to guarantee secure, sustainable and inclusive economic growth. It is one of the most cost-effective ways to enhance security of energy supply, to boost businesses’ competitiveness and to reduce the environmental burden of the energy system. The cost of energy efficiency will dampers the increase of the energy consumption. The main actor in this transition are the consumers from one side and the major actors of the energy industries. Through the efficiency and the new technologies, the consumers will reduce the consumption, on the other side the major actor will try to provide the energy requested.