Worldwide energy consumption is projected to double by mid-century. For the next several decades, the world will continue to depend heavily on fossil fuels, even as renewable resources are increasingly used. To reduce the climate-changing influence of fossil fuels, a significant fraction of the carbon dioxide they produce needs to be captured and stored away from the atmosphere. (For a discussion of proposed geoengineering measures see page 26.)
Nuclear energy, by contrast, produces no significant CO2, which makes it an appealing alternative to carbon-based fuels. But its radioactive waste materials have their own environmental and security implications. To sustain current levels of nuclear energy—and especially to increase production by a factor of 10 or more during the 21st century—it is necessary to store radioactive waste in underground repositories. Several countries, including the US, have programs under way to develop such repositories for nuclear waste as well as...
