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We must increase the understanding of fast nuclear reactors so there will not be such great opposition to their use for zero carbon energy.



We live every day with mild toxins (car exhaust, alcohol, etc.) and think nothing about them, because we understand them.  Education will let us treat nuclear reactors with similar understanding.

Fast neutron reactors can reduce greenhouse gas emissions because nuclear is a zero-carbon energy source.  At the same time as they are able to supply the large amount of energy needed to help the poor countries increase their standard of living they can also supply the energy needs of the rest of the energy-hungry world.  Besides providing this energy, fast nuclear reactors will be able to provide for a population increase of 20 million people every year.  Meeting the energy needs of the whole world is an extremely complex issue; it can divide us into those who realize that nuclear can provide abundant energy without greenhouse gas and those who are adamantly against anything nuclear.

A fast reactor uses higher energy neutrons to initiate fission of uranium, plutonium, and thorium.  The fast reactor can provide energy for the whole world without the problems many associate with nuclear power.  Two example kinds of fast reactors are known by the acronyms PRISM (Power Reactor Innovative Small Module) and IFR (Integral Fast Reactor;) both are in a grouping known as Generation IV reactors.  The IFR is a total system even including fuel reprocessing; that’s where the “Integral” part of the name comes from.  This reactor uses non-pressurized liquid sodium for cooling.  The fast reactor can use as fuel the "waste" from thermal reactors, the warheads from decommissioned nuclear weapons, and the many tons of depleted uranium (isotope U-238) left over from our uranium enrichment program; in addition it can use thorium (Th) after transmutation to U-233.

In order to reach the eventual goal, abundant energy with less greenhouse gas, additional actions will be required during the educational phase, which is this proposal: Funding, Design, Siting, Construction, and Putting in Service. 

Category of the action

Reducing emissions from electric power sector.

What actions do you propose?

Quoting Tim Elliott emphasizes education as the first goal: "Mitigating risk people don't understand is almost pointless."  Therefore, people must understand nuclear reactors before they will be receptive to even better reactors.  Instead of mitigating the already small risk, we would be getting them to  accept fast nuclear reactor energy generation through understanding.

There are at least three avenues that need to be pursued to help people understand the safety and capabilities of the fast nuclear reactor; these are: Congressional, Regulatory, and Public Opinion.   The third will cause a substantial drag on allowing the Congressional and Regulatory avenues to provide what is required.  Because they don't understand fast reactors, all three have thermal neutron reactor problems in mind whenever nuclear reactors of any kind are mentioned.  Therefore, the first required action is to increase the understanding of fast neutron reactors for all three avenues.  That is, negative perceptions have to be guided to a better understanding of the benefits and abundant energy fast nuclear reactors can provide while also reducing greenhouse gasses.  Note that the Congressional and Regulatory avenues can and should take action before Public Opinion becomes favorable; this is because some of the public is highly resistant to nuclear reactors to the point that nothing will change their opinion.

Even before the educational phase is completed, actions by Congress and Regulators will be required in order to reach the goal—abundant energy with less greenhouse gas:

--Funding.  Funding is probably the most important part of the Congressional avenue; funding was cut off in 1994 for political reasons and needs to be reestablished so that development and construction can proceed.  The public needs to understand that it was politics, not science, that caused funding to be cut.

--Design.  Much design and development has already been done, but a prototype system should be built and demonstrated.  The education phase and the design phase should be done simultaneously.

--Siting.  In many cases the fast reactor can replace the fossil-fueled heat source at existing generating plants in order to utilize the existing infrastructure—the generators, substations, transmission lines, and distribution network.  Of course many totally new sites will be needed world-wide in order to substantially increase the total generating capacity so electrical energy can be provided to those who are now underserved.

--Construction.  After a small amount of experience, the fast reactor design can be standardized to make manufacturing and permitting easier, faster, and less costly.  For areas that are remote or have smaller power demands, a totally shop-built reactor will be possible.

--Putting in service.  This will include fueling and startup.  Startup requires a small amount of fissile material (plutonium mixed with uranium-235) which can be obtained from other fast reactors.  After startup, the nuclear reaction will be self-sustaining.

The overview below is some of the information that can be used in the education phase.  It is directed to increasing the understanding of fast reactors so that Congress, Regulators, and the Public can better evaluate their benefits.  Some of the Public, enhanced by media hype, seems to be particularly resistant to understanding that fast reactors are the least dangerous and best solution to the energy hunger and climate change in our world.  This means that the media can be a tremendous help in the education phase and should, therefore, be one of the first groups involved so that they can become an ally.  As noted above, Congressional and Regulatory actions can and should be independent of Public Opinion.

There are several types of fast reactors, all of them having similar benefits.  I think the Integral Fast Reactor (IFR) is better, because its metallic fuel uses a reprocessing chemistry (pyroprocessing) that makes separation of plutonium (Pu) and uranium-235 (U-235) quite difficult; this greatly reduces the risk of proliferation.  (Most other designs use oxide fuel which uses chemistry (PUREX) that was specifically designed to separate Pu for use in weapons.)  Many people worry about proliferation caused by diverting reactor-generated plutonium to non-peaceful uses.  This cannot happen with the IFR, because the proposed and demonstrated reprocessing chemistry is unable to separate plutonium from the other fissile and fertile material; the mixture will go back into the IFR as fuel for extraction of the energy in it. 

The public also needs to understand how plutonium is made inside the reactor by transmutation.  Starting with the uranium fuel, the uranium-238 isotope absorbs a neutron and has two quick beta-minus decays to become neptunium-239 then plutonium-239.  Beta-minus decay is the changing of a neutron to a proton, thus increasing the atomic number, by ejecting an electron which is also known as a beta particle.  For those who are counting, beta-minus decay also ejects an antineutrino.

Fast neutron reactors can be called an “elegant” solution, because “All the pieces fit together” as Hans Bethe said when talking about the Integral Fast Reactor (IFR).  This is because the many components complement each other—they bring out the best features in the other components.  The fast reactor has a set of many desirable characteristics compared to the thermal reactors that are primarily used today. 

Carbon dioxide is one of the greenhouse gasses (GHGs.)  CO2 pollution is a huge world-wide problem, because it is a contributory cause of global warming which affects climate change.  Much of this CO2 comes from coal and natural gas-burning electric power plants.  In addition to the CO2 from both of these fuels, the coal-burning plants release large quantities of radioactive material into the environment: 5 tons of uranium and 7 tons of thorium every year for a 1000 MWe (mega watt electrical) power plant.  These elements are spread across the countryside by the wind.  Thus coal-burning plants release far more radioactivity into the environment than is permitted from nuclear reactors.  In addition to concerns about the radioactivity released by coal-burning plants, consider that they also release mercury, lead, beryllium, arsenic, thallium, and heavy metals.  This tells us that replacing coal-burning plants with nuclear plants will save lives and improve health in addition to putting less CO2 into the environment. 

The thermal reactor has problems with used fuel, which is often called “waste,” because it contains intensely radioactive isotopes that remain radioactive for a very long time.   This thermal reactor “waste” should actually be called “used fuel,” because it can be used again in fast reactors.  A thermal reactor uses less than 1% of the energy content of the uranium fuel before the buildup of fission products absorbs too many neutrons for the reaction to continue; but the IFR can take this used fuel, after reprocessing, and get additional energy from it by completing the burn-up to over 99%, thus increasing by a factor of about 100 the amount of energy we can get from a given amount of fuel.  This greatly extends the time that our present fuel stockpile will serve; mining will not be required for several hundreds of years. 

Again, for the benefit of the Public: the present thermal reactor “waste” does not have to be stored, but can become fuel for use in a fast reactor which will more efficiently extract energy from it while producing much less waste in both volume and radioactivity.  This, of course, means that the thermal reactor “waste” now in storage throughout the country and the world can be used as fast reactor fuel resulting in a gradual reduction in the amount of stored thermal reactor used fuel.

The IFR is a safe reactor—it will shut itself down if it overheats due to loss of pumped coolant flow.  Fuel melting due to loss of coolant flow is a big worry with the thermal reactors (an example is the Fukushima accident in Japan,) but the IFR will shut itself down with no automatic or manual intervention required (what is called “negative reactivity.”)  From an article by Mary Jo Rogers: “It is now safer working at a nuclear power plant than in a school setting;” this was written about thermal reactor safety; the IFR is even safer.

Residual heat remaining in the reactor core after shutdown is another big concern with thermal reactors, because of the possibility of steam explosions and melt downs.  With the IFR, cooling will continue by convection; in addition there is less heat stored in the IFR’s metallic fuel because it is more conductive than the oxide fuel used in thermal reactors; this allows the IFR to operate at a lower fuel temperature.  In addition, the liquid sodium coolant has a large heat capacity and a much higher boiling point; this means it can absorb more heat without a large temperature increase, and that there can be a much larger temperature increase before coolant boiling occurs. 

The liquid sodium coolant is not pressurized, which reduces the strength requirements for the primary containment vessel.  Of course less required strength means less material and less cost. Some people are concerned that liquid sodium has a violent reaction in the presence of water.  True, but through extensive industrial experience we have learned how to handle it safely.  In addition, because the sodium is not pressurized, any leaks are not serious.

The IFR does have waste, but it is a much smaller volume, and the radioactivity does not last nearly as long (scientists use the term “half life” to measure this.)  The required isolated storage time for thermal reactor used fuel is many hundreds of thousands of years, but the IFR waste needs to be stored only a few hundred years, because the highly radioactive and long half life components, known as transuranic actinides, which are the man-made elements beyond uranium in the periodic table, have been used to produce energy and thus are no longer included in the waste. 

If the thermal reactor used fuel is not stored on-site, it requires transportation to a central storage area or to a reprocessing facility (we now have neither).  The fast reactor used fuel can be reprocessed on-site, as in the IFR design, separating it into usable fuel and waste.  Or it can be transported to a central reprocessing facility.  However, the need for transportation of the waste is greatly reduced by the smaller volume, and perhaps can be eliminated entirely if the waste is stored on-site at the reprocessing facility. Transportation is of concern because the possibility of accidents upsets many people even though the shipping containers are designed to survive a severe accident. 

As mentioned above, there is concern that in switching to fast reactors we would abandon the infrastructure that has been built for the coal-burning generating facilities.  However, it is possible for the fast reactor to be the heat source to replace the coal-fired boiler but use the generating equipment, substations, and transmission lines already in existence.

The above focuses on some educational considerations that can be used to increase the understanding of fast nuclear reactors by Congress, Regulators, and the Public.  In order to reduce greenhouse gasses by replacing coal and natural gas generating plants, many actions need to be accomplished: funding, design, siting, construction, and then putting the fast reactors into service .  Several of these actions can be happening at the same time.  The implementation of all of these will be much smoother if everyone understands the benefits and reasons; thus the need for education. 

Of course some will want to know why renewable sources such as wind and solar energy are not recommended for the world’s power needs.  Besides the intermittency problem, there simply isn’t enough potential capacity to satisfy the world’s increasing hunger for electric power.

Who will take these actions?

Those taking action in the beginning will be those who realize the potential benefits of fast nuclear reactors.  The initial education efforts should be to the media, because they can become a tremendous help in guiding others to a better understanding of fast nuclear reactors.  "Others" will include, in the USA, Congress, Regulators, and rest of the Public (I am using the media as a subgroup of the Public.).  Of course Congress and the Regulators can and should take action independently of the Public, but their actions will be much easier if the Public understands and approves; that is, there will be less negative reaction from the Public. 

Where will these actions be taken?

The field of action has to be the entire planet Earth, because the affordable energy supply has to increase many fold while producing less greenhouse gas.  The USA will need more energy as time goes on; but, for third world countries, the increase in energy needs will be huge because they have so little now.  I am, of course, most aware of the lack of understanding of, and thus the vocal resistance to, nuclear energy in the USA; but the education efforts have to include the entire world, because climate change is and will be a world wide problem.

How much will emissions be reduced or sequestered vs. business as usual levels?

I cannot properly estimate the total worldwide reduction of greenhouse gasses, because it is such a complex endeavor, and because there would be too many assumptions.  But I can confidently state that energy produced by any nuclear reactor will produce zero greenhouse gas, because nuclear reactions are not a combustion process.  In particular, carbon dioxide will not be produced by fast nuclear reactors.  The more coal and natural gas fired electricity generating plants we can replace with fast nuclear plants, the more carbon dioxide can be eliminated; not to mention all the other pollutants released by coal fired generating plants.  Thus, greenhouse gas reduction at any future date will depend on how many fossil fuel burning plants can be replaced, and how many new plants can be non-fossil fuel.  If no action is taken, the worst case result will be severe flooding of coastal areas plus a drastic change in weather patterns and life as we know it.

What are other key benefits?

Most important is our goal of climate improvement, but of almost equal importance is making  electrical energy available where it currently is not accessible and where it does not meet the needs of society.  Thus energy availability, a byproduct of the reduction of greenhouse gasses, enables improvement of the standard of living primarily for the third world countries where it will have the greatest impact.  There will also be health benefits due to the elimination of coal-burning electrical energy plants.

What are the proposal’s costs?

The purpose of this proposal is to start and continue the process of educating Congress, Regulators, and the Public so that they understand fast nuclear reactors and their benefits to the world.  It was suggested above that the media is a vital part of the education of the Public; this is true because, once the media understands, they will provide a lot of free-to-us publicity on the subject which will help increase the understanding of the Public.  It might even be that knowledge and understanding of fast nuclear reactors will increase exponentially--to use one of today's fad words.  This naturally means that resistance will decrease exponentially.  This also means that costs will decrease, because negative public perceptions, which drive many costs, will be reduced.

Estimating the costs of this educational process is difficult, partly because so much free-to-us publicity will become available soon after the process is started.  I will guesstimate that the cost will be about $1 million.  Note that this is for the initial educational phase, and does not include design, permitting, and construction.  For these later phases, because the cost of first-of-kind is always much bigger, getting the first fast reactor built and in service will be quite expensive.  After the first, the cost will drop quickly as additional units are built, and designs are standardized.  Operational costs will likely be less than the current cost of electric power; also remember that the fuel is basically free since so much is already on hand, but it does have to be put into a usable form.

Time line

Reduction of the greenhouse gasses produced by generation of electricity by combustion of fossil fuels has been needed for years, so action on this proposal should be started as soon as possible, not phased in, because of the risks if we don't.  When we will see results is impossible to say due to the complexity of the task, but I will estimate five years.  Even after this proposal shows positive results, that is, when approvals for construction are obtained, it will take several years to finalize design, construct, and activate a fast nuclear reactor.

Related proposals

Almost everything on the planet Earth is interrelated.  The reduction of greenhouse gasses by drastically reducing the use of fossil fuels to generate electricity will, of course, bring about vigorous complaints by the coal and natural gas industries.  But there will be benefits that more than compensate.  As the greenhouse gasses are reduced by converting electricity generation to fast nuclear, the death rate from fossil fuel pollutants, mostly from coal, will be reduced.  The greater availability of electric power will allow the standard of living of third world countries to increase.  Less global warming will reduce the worries about flooding of low-lying lands.  Plus many effects that we cannot begin to imagine.


In addition to numerous clippings from magazines, newspapers, and websites; my main sources of information are two books:

--Plentiful Energy, the Story of the Integral Fast Reactor by Charles Till and Yoon Il Chang.

--Prescription for the Planet by Tom Blees.