Sunday, September 29, 2019

Nuclear: Unending Toxic Legacy

                                                                                           written 22 September 2019
                                                                                            posted 29 September 2019
            The American destruction of Hiroshima and Nagasaki introduced the devastating power of nuclear energy.  Despite ending the war, the unprecedented use of such force on civilians was a public relations problem.  So, America created "Atoms For Peace", generate electricity with nuclear energy, promising "power too cheap to meter".  The first commercial nuclear reactor went online in 1957. Today there are 98 reactors in America and a global total of 488, producing about 10% of the planet's electricity. 
            But nuclear power has never been too cheap to meter.  Reactors are expensive to build, running over budget and behind construction schedule.  The relatively small number constructed precludes the advantages of mass production. Unforeseen problems produced design changes and costs overruns.
            Compared to efficient gas fired plants or renewable energy, a nuclear plant is not cost effective.  The investment bank Lazard calculated the following operating costs per mega-watt hour: nuclear at $97-$136, combined cycle gas at $52-$78, grid scale thin film solar at $50-$60, and wind at $32-$77.  Renewable costs are going down as manufacturing scales up, and reactor costs are increasing.  Utilities are shutting down existing reactors before the end of their design life, with few orders for new reactors, because nuclear is a free market failure.
            But nuclear boosters never give up.  The current promise is that nuclear is "green" energy, and can help deal with the climate problem.  But this is as misleading as the promise of free electricity, even though some important environmentalists support this path.  While it is true that a nuclear plant produces no CO2 during normal operation, it is important to look at the whole life cycle of a plant.  This includes the energy to produce the fuel, build the plant, and dismantle it at the end of life.
            A recent IPCC life cycle study reported nuclear was better than solar on carbon emitted.  The study calculated grams of carbon released per kilowatt-hour over the life of the equipment: natural gas at 469g, solar PV at 46g, nuclear at 16g, and wind at 12g.  Not included was the carbon cost of decommissioning a reactor, or disposing of radioactive waste, problems unique to nuclear power.  This omission is understandable because there is little experience with either issue.  
            Of the 150 reactors that have shut down, only 19 have been completely decommissioned, with just 10 returned to "greenfield" condition, free of all radiation contamination.  Most of the decommissioned reactors were relatively small compared to the 1,000MW units in general use.  Decommissioning is expensive, costing almost $1B for large units, and can take decades, because reactors are not designed to be dismantled, and everything is radioactive, not recyclable, requiring special disposal.  Entombment in place is cheaper than dismantling, but leaves a toxic legacy for centuries.  The International Atomic Energy Agency estimates $1T to entomb the entire fission industry.  
            Decommissioning a damaged reactor is more expensive and time consuming, because of the increased radioactivity.  Fukushima is estimated to cost $100B and take 4-5 decades, which are optimistic guesses. Chernobyl blew up 30 years ago.  Despite the $20B already invested, the second containment effort is about to fail. 
            Nuclear power requires fuel rods be reprocessed, creating quantities of highly radioactive waste, which can be diverted into nuclear weapons.  Only time can destroy radioactivity, and secure geologic sequestration is the only strategy developed so far.  Despite 70 years of nuclear production there are few high-level waste depositories in operation, leaving most of the burden stored at reactors or fuel reprocessing sites.  The last proposal for the Yucca Mountain repository in Nevada included air conditioning for a century in order accommodate more material, with uncalculated carbon emissions.  
            This waste is the grossest example of externalized costs, where a few take the immediate profits, and leave the costs to everyone else.  The nuclear industry has consistently minimized concerns about the health impact of radioactive material, allowing unaccounted dispersion of this contamination.  Some is toxic for over 100,000 years, burdening thousands of future generations.  
            Climate change is a huge challenge, a symptom of our disregard for the connected whole.  Radioactive contamination is another symptom of that disregard.  It is morally repugnant to avoid carbon by creating this toxic legacy.  "Green" is a healthy and sustainable future: nuclear power is neither.