An article in the December issue of Scientific American describes some new technologies that have developed that will make conventional nuclear power plants safer and more environmentally sound than what we currently have. This is a timely article since there has been a call for more widespread use of nuclear power in the national energy plan that has been pushed through by the Bush administration and Congress.
In this day and age of terrorism (possibility of dirty bombs and sabotage of nuclear power plants), oil dependency from the Mideast, and tons of spent nuclear fuel that is dangerous, toxic waste that will be around for millennia, it is no wonder that one’s reaction to more nuclear plants is one of disbelief and fear. There is no question that nuclear power is an attractive energy source because there is little in the way of gaseous emissions that can cause illness and contribute to global climate change as we get from conventional gas and coal burning power plants. There is a supply of uranium that will last long after our oil and gas reserves are spent (if we maximize its use), and it is an efficient energy source. It has been the public and political fear factor after Three-Mile Island and Chernobyl that has prevented the U.S. from building new plants over the past thirty years.
However, I read with much interest the new technologies that may allow the re-birth of this industry in the next decade. The first innovation involves using a high-temperature method (pyrometallurgical processing) of recycling normal reactor waste products from fission reactions into new forms that can then themselves be burned in a modified type of reactor called an advanced fast-neutron reactor. The trouble with present-day thermal, slow-neutron reactors is that, while efficient in terms of electricity generation, they cannot minimize the output of radioactive waste. In addition, something I wasn’t aware of, when reactor technicians remove and replace the uranium fuel in reactors, only 5% by weight of the ore has actually been used in energy production. The remaining 95% is unused uranium-235 or waste products, including transuranic elements. With other nations increasing their numbers of nuclear reactors, and likely the U.S. will start building more within the next ten years, the world’s uranium supply may only last fifty years. A new way of harnessing the electricity potential of uranium ore needs to be employed if nuclear power from fission is a viable long-term alternative energy source.
The fast-neutron reactor, though, in conjunction with new recycling methods used on nuclear waste products, have been shown to solve many of the traditional problems with nuclear power. Fast reactors (which have been around since the late 1960s) already exist in France, Japan, Russia, the U.K. and two plants in the U.S. Using full recycling on wastes from thermal reactors, for instance, can lead to about a 1% amount of wasted energy potential from uranium ore, versus the 95% wasted energy potential we now have. The relatively small amount of waste products only contain trace amounts of transuranic elements such as plutonium (needed for weapons) and americium; these are some of the wastes that currently are troublesome since their half-lives are tens of thousands of years or more, depending on the isotope, and the question is what to do with all that toxic waste. The storage issue as well as black-markets selling weapons materials to rogue nations or terrorist organizations requires us to minimize the amounts available, meaning the new recycling methods may help significantly reduce the problem. What little waste is left from fast reactors typically is a problem for 500 years, still a long time, but much better than tens of thousands of years and much smaller quantities to store in a facility like the proposed Yucca Mountain site. A third consideration is the lack of greenhouse emissions from nuclear facilities, which means such reactors would not contribute to global warming.
While there would still be a waste issue with fast reactor and recycling technologies, they would be minimized for fission-based reactors. Weapons materials would not be produced in any significant amounts, toxic waste would only be produced in small amounts which would need to be stored for far shorter periods of time than what wastes we now have, and there would be no climate change contributions. The global uranium supply lifetime would be extended well beyond what it would be with thermal reactors, and far beyond what is projected for oil and gas reserves. These new technologies seem to make fission-based nuclear power much more attractive than only a few years ago, and may be worth pursuing. While I would want much more research before doing this on a large scale, it seems as if the fast reactors that already exist are working well, and large-scale recycling facilities would need to be built in unison.
Of course, this is not the only option for power production. Wind power is the fastest growing type of energy production, and I would like to see significant increases into funding for the R&D of new solar technologies (these need to be made more efficient for widespread use, and new storage techniques need to be developed for cloud days/nights). There are good possibilities with geothermal power as well as harnessing the endless energy of ocean waves, the tides, and ocean currents. Then, of course, there is the possibility of hydrogen-based power, such as fuel cells.
Either way, nuclear power will almost certainly be a part of future energy strategies for the U.S. and numerous nations around the world, as planning for the end of the oil era must begin now. This is not the sort of thing we can wait for because every aspect of our society now revolves around energy, and economic disaster (as well as potential environmental and security disasters) awaits those who do not have viable plans and massive amounts of new energy infrastructure developed over the next few decades. We must get serious now about our energy use and sources of energy production because of the enormous amount of infrastructure construction that will be needed.
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