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Why would anyone consider nuclear power for making electricity?

Robert Hayes Published: August 2, 2013

The capability for using nuclear technology to make electricity was demonstrated over 60 years ago.  Many people still fear anything with the word nuclear in it and may even think the word nuclear is not too different from being dangerous.  In truth, every atom in the universe has a nucleus and to discuss that part of an atom is literally a conversation regarding nuclear science.  If that science is to be utilized for anything such as medicine, manufacturing or even oil exploration, that nuclear science becomes nuclear technology.

Nuclear power when making electricity has a large number of advantages in terms of being environmentally friendly.  It does not generate green house gasses and has the highest ratio of energy output per manufacturing and construction energy required to install its capability*.  For example, to install solar panel capability, the amount of energy required to build, install and maintain the solar panels is around 5 times less than the energy which will be extracted from their use.  In other words you will get 5 times more energy out of the systems than was required to build and install them so if a commercial solar panel plant requires 10 MJ in energy to create, it will only produce 50 MJ in its lifetime on average.  With traditional nuclear power, you will extract more than 20 times more energy than was required to build and install the system.  Using the ultra low energy centrifuge enrichment process at URENCO (http://www.urenco.com/page/33/URENCO-USA.aspx), this number can increase to as well over 50.  Only hydro power (from damming up rivers) has a number as high as 50 for commercial power generation with wind energy falling behind that.

It may be surprising to hear that nuclear power generates relatively little waste.  This last aspect of nuclear power may be surprising because the waste issue for many is the only real drawback for utilizing nuclear power given there is no permanent geological disposal option currently available for spent nuclear fuel or high level waste.  Technically, the solution of geological disposal has already been demonstrated at facilities such as the WIPP (http://www.wipp.energy.gov/) although the path forward for this technology has historically been politically unviable.  This in spite of the fact that nuclear energy has been shown to be highly effective and in most instances extremely cost effective.

Consider the very familiar barrel of oil.  In a single barrel of oil, you have an approximate energy equivalent to 460 pounds of coal or 5680 standard cubic feet of natural gas.  In terms of heat energy output, this same energy could be created from just over 70 mg of Uranium-235 fissioning.  Equivalently 1 cubic centimeter of fissioning Uranium 235 is generates the same heat energy as over 250 barrels of oil and over 100,000 pounds of coal.  In other words, an extremely small amount of nuclear fuel is equivalent to a very large amount of fossil fuel in terms of energy content.  Note that when you burn the organic materials to make the heat needed to produce electricity in a steam cycle generator, you get a larger combined mass of greenhouse gasses and ash than the fuel mass you started with (due in part converting breathable oxygen into the greenhouse gasses through the combustion process).  With nuclear power, the spent fuel mass does not measurably increase at all but actually decreases due to conversion of mass into energy through the nuclear reactions (hence the relatively small amount of waste generated from nuclear power).  The real difference comes from the concentration of energy available with nuclear power.  Considering fissile Uranium, there is over 100 million times more energy available per reaction than in crude oil, natural gas or coal.  In addition, some coal has been found to have such a high naturally occurring radioactivity content (such as uranium, thorium, potassium and radium) that when this coal is burned to ash, the amount of radioactivity per megawatt extracted is higher for that coal than that generated from nuclear power.  This of course is due to both the substantially smaller mass of waste obtained from nuclear and the extremely concentrated amount of energy which can be extracted from fission.  Of course this only applies when you use those units of radioactivity per electrical energy generated.  Furthermore this coal ash will be distributed over a very large number of railroad cars of waste materials with the spent fuel being concentrated into only some 10′s of cubic meters of waste.  The case for nuclear power is truly compelling from a scientific point of view, politically it is often seems to be viewed quite poorly.

* Please see http://www.ans.org/pi/resources/brochures/docs/greening.pdf and references therein for further details.