ericgrimsrud

While the use of nuclear reactors for energy generation has a spotty history and remains controversial today, I believe that we should greatly increase our investments in this area.  Just one of my reasons for this was allegedly expressed by the gangster Willy Sutten – when asked by a reporter why he robbed banks, his answer was reported to be “because that’s where they keep the money!”

Similarly, it is within the atoms, not molecules, where serious quantities of energy are stored and it is through the controlled nuclear  transformations  that can be made to occur in modern reactors that that energy can be reliably and safely released.  “Ya but”, I can already hear many of you saying.  So in order to get past some of those negative reactions instantly aroused whenever the word “nuclear” is used, let’s consider some of the actual history of the nuclear reactor developments that began in the USA in the 1940’s.

In describing that history, it is useful to divide the nuclear reactors thereby built or envisioned into four classes. Class I plants were based on relatively primitive graphite-pile reaction cores – first developed during the Second World War for the purpose of making the fissionable nuclide, Plutonium-239, that was used in two of the three atomic bombs first developed in 1945. The nuclear reactor that exploded at Chernobyl in the Russian Ukraine in 1986 was a distinctly outdated and primitive Class I reactor.

The Class II reactors were also developed in the mid-twentieth century and include most of those in use today. They are based on much safer and more controllable water-based reaction cores. The reactors that were recently overwhelmed by the tsunami that hit Fukushima, Japan, in 2011 were 30 to 40-year-old Class II reactors.

The few new reactors that are being built today are Class III reactors. They are based on the same principles as Class II reactors but include new technologies for increased safety, control and longer useful lifetimes.

Class IV reactors are still in their development stage and various versions of them are expected to come on board gradually in the next several decades. They are generally based on the use of a liquid metal (such as sodium at high temperature) as the core moderator. These “fast-flux” reactors, as they are called, are capable of “burning” all of the heavy elements put into their core. For example, naturally-occurring uranium contains less than 1% of its isotope 235 and this isotope, only, undergoes nuclear fission in conventional reactors of the types I, II, and III. In a class IV reactor, uranium-238 which constitutes over 99% of natural uranium is converted to other heavy nuclides which then also undergo nuclear fission. In this way, all of the uranium added to a Class IV reactor is burned. Note also that the Earth contains an almost inexhaustible supply of uranium-238 and other heavy elements that can be used in Class IV reactors. Even the massive amounts of waste products accumulated from our prior use of the older reactors can be used as fuel for Class IV reactors.

Another great advantage of Class IV reactors is that their radioactive wastes are much easier to deal with. They produce far fewer radioactive wastes and these consist only of elements in the middle of the periodic table with radioactive half-lives much shorter than the waste products of the conventional reactors.

In retrospect, it was clearly a mistake for the USA to discontinue its research and development in the area of nuclear power plants some 30 or more years ago.  But we did not know then as well as we do now the problem that would be posed by our continued dependence on fossil fuels. We do now know, however, that the problems posed by the use of fossil fuels are probably not solvable while those associated with nuclear fuels are solvable. So even though we have squandered several exceedingly important decades that might have been better used to address our current global warming problem, it seems to me that we should get back on the nuclear track ASAP.

It also seems pretty clear to me that the world’s future energy needs must be met by a combination of renewables, nuclear, and increased efficiencies while CO2 emissions are cut to near zero within the next couple decades – no matter what pain and sacrifice  might be required to make those cuts.  Anything less might very possibly render all other future endeavors of mankind pointless.  A new film called “Pandora’s Promise” will also presents the case for “green” nuclear power and will be aired on the evening of Nov. 7 on CNN (9 pm Eastern).  Please watch it.  After all, it is within the nuclei of the atoms that the bulk of our energy is stored.