However, the last years have also seen a number of important shifts, such as the rise in shale gas production, especially in the United States, the decrease in nuclear energy after Fukushima, as well as a slight increase in modern renewable energy (PBL Netherlands Environmental Assessment Agency, 2013). Essentially, this would require making the power and transport sector carbon-free worldwide by mid-century, in view of the limitations associated with replacing industrial processes based on fossil fuels. Todays C02 emitting devices and infrastructures alone imply cumulative emissions of about 496 gigatons (Gt) of C02 from 2010 and 2060, leading to atmospheric concentrations of about 430 ppmv (Davis, Caldeira, and Matthews, 2010).