The International Energy Agency, for instance, has compiled a number of “golden rules” for exploiting natural gas in a sustainable way, such as treating water responsibly and surveying the geology of the drilling area (IEA, 2012). Figure 5.2 illustrates the breakdown of the investment needs. For instance, the USD 1.4 billion needed for renewable energy is a fraction of the USD 14 to 18 billion needed for the energy sector overall during the same period. Also, while energy efficiency requires up to USD 150 million in investments, it could lead to important financial savings as well.