Looking at Jesse Ausubel's Nuclear Future

PopsciJesse Ausubel is the director of the Program for the Human Environment at the Rockefeller University in New York City. He shares some imaginative visions of a future where nuclear energy is the dominant form of power.

Simultaneously a technology-loving futurist and an ardent naturalist, Ausubel points out that a wind farm delivering the same energy as a 1,000-megawatt nuclear plant would cover 308 square miles; a solar plant, 58. Even organic farming, he suggests, is justifiable in the context of landscape preservation only if the per-acre yields equal those of conventional farming...

...Ausubel has spent most of his career modeling a future that assumes a population of about 10 billion—what many experts believe the world will bear over the next century—and reasoning backward from there to explain how such a world could be powered and fed, and how much land could be spared for nature.... instead of using policy to change how people will behave in the future, Ausubel prefers exploring technological responses to what he believes people are going to do regardless. His favorite defense of this laissez-faire approach is to explain that, absent any policy dictating that it should happen, energy consumption over the past 100 years has steadily “decarbonized.” That is, humankind has moved to fuel sources with progressively better ratios of carbon atoms to hydrogen atoms—wood at 10:1, coal at 2:1, oil at 1:2, natural gas at 1:4 and, eventually (in the future Ausubel envisions) 100 percent hydrogen.

...ENERGY: Within a few decades, after methane plants have replaced coal plants, according to Ausubel’s decarbonization model, the move is on to full nuclear. His plants would produce electricity during peak daytime hours and be used to dissociate water to make hydrogen by night. “With the nuclear industry making two products instead of just one,” he says, “the economics become more attractive.”

Where to get all the uranium for the hundreds of new nuclear plants that Ausubel’s world would require? Extracting it from oceans, he believes, could supply enough energy for 10,000 years or more. The low concentrations in seawater—about 3.3 parts per billion—make the extraction process difficult, but Japanese researchers have successfully mined uranium from ocean currents, although not yet at costs that would be economically feasible.

NUCLEAR WASTE: Ausubel cites Russian and British research into “self-sinking balls” of nuclear waste with shells most likely made of tungsten and heated by their radioactive contents to the point where, once disposed of in deep holes in the Earth’s crust, they would melt the surrounding lithosphere and bury themselves several miles deep. “Nuclear waste is hot and heavy,” he says. “The idea of self-sinking capsules takes the heat and gravity as positive attributes. The idea is quite straightforward.”

.... _Popsci

In reality, of course, most "nuclear waste" will have intrinsic value in important processes -- including helping to fuel newer generations of fission reactors. But there will be a small percentage of spent fuel which will need to be safely and reliably disposed of. Burying such waste deep in the Earth's interior would ultimately lead to long term dilution -- which is all that you really need to obtain to make it safe.