The God Species_ How the Planet Can Survive the Age of Humans - Mark Lynas [43]
Second on my list, and related, is the development of electric vehicles that are easy and quick to recharge and can travel several hundred kilometers without having to carry most of their weight in heavy battery packs. We need much more efficient and cheaper batteries that do not use rare earth minerals like neodymium, terbium, and dysprosium, currently essential components of electric cars but likely to grow scarcer in decades to come.81 Still looking at transportation, an even greater technical challenge will be to decarbonize aviation, or at least find a way to allow speedy international travel over oceans without heavy carbon emissions. As with cars and electricity, people are not going to give up flying long distances, so some solution must be found to tackle aircraft-generated carbon. One conceivable option is liquid biofuels (if truly sustainable sources on the scale needed can be found); another is hydrogen-burning jet engines. At the moment there is no clear answer, but the entirely implausible today may become obvious tomorrow: That is the job of RD&D.
Third for me would be the development at large scale of carbon capture and storage (CCS) technology, to strip CO2 out of power-station waste gases and pump it safely into saline aquifers or stable rock formations underground. There is a strong argument that countries like China that possess a large amount of coal are going to burn it anyway—so finding ways to stop the resulting carbon dioxide hitting the atmosphere has to be a big priority. Currently several test projects are up and running around the world, but despite the political attention given to “clean coal” none are running at the scale of a large power station. An additional reason to make CCS work is so that biomass power plants could be built that would actually be carbon-negative. The vegetation burned in them would have absorbed carbon from the atmosphere while the plants grew, so injecting the resulting carbon dioxide underground would strip this from the atmosphere. If deployed at a large enough scale in future decades (and assuming this did not overly affect land use and food production), this could be a useful tool for meeting the 350 ppm goal.
Fourth on my list but equally revolutionary in its potential is next-generation nuclear technology, which could improve substantially on the designs used in civil nuclear plants in the past. Particularly exciting is the Integral Fast Reactor (IFR) concept, for which a prototype was nearly completed at the U.S.’s Argonne National Laboratory in the early 1990s but was canceled for political reasons by the Clinton Administration. Because IFRs would be “fast breeder” reactors, they could utilize much more of the potential energy in uranium fission: In conventional reactors, only 1 percent of the fissionable energy is used from the natural uranium and the rest becomes waste. Another attractive potential for IFRs is for them to generate zero-carbon electricity by burning up stockpiles of existing long-lived nuclear waste, while producing waste themselves whose radioactivity declines back to that of the original uranium ore in just 200 years.82 Another option seriously worth exploring is thorium as a reactor fuel, as it is much more plentiful than uranium-235, produces less waste than conventional reactors, and does not yield anything that might be useful for nuclear weapons in the hands of rogue states.
Even if we stick with uranium, there is no conceivable shortage of fuel for IFRs. While there are real fears that limits on accessible reserves of conventionally used uranium-235 might put a ceiling on worldwide nuclear reactor deployment, IFRs can burn up so-called “depleted uranium,” or uranium-238, of