Bill Totten's Weblog

Monday, December 20, 2004

The Energy Challenge 2004 - Nuclear

by Murray Duffin

http://www.energypulse.net (October 08 2004)


No aspect of the energy challenge is more polarized than that of nuclear energy. Both the pros and cons are very selective in presenting their arguments, and it is very difficult to get a balanced or objective view of the real trade-offs. While much of the opposition is emotional, deriving from fear of radiation, bombs, and Chernobyl, it is not unlikely that this polarization also arises from the fact that, at present, there may be as many real negatives as positives.

The Pros:

The main plusses presented in favor of nuclear are:

<> There is a limitless fuel supply.

<> It is non-polluting, particularly having no carbon dioxide emissions.

<> It has very high energy density, requiring the least fuel for the energy provided.

<> It is inexpensive, the produced electricity being cheaper than coal.

<> It contributes to our national security.

<> New technology will make it 100% fail safe.

<> It already provides 20% of our electricity.

<> Nuclear generated electricity costs only 2 cents per kilowatt hour.


When these claims are examined in detail we find that:

<> The fuel supply is only relatively limitless, and then only if we use fast reactors, and their development was suspended in the USA in 1994.

<> Mining the ore, refining it, and concentrating it to make it fissionable are very polluting processes. If the whole fuel cycle is considered, nuclear produces several times the carbon dioxide that wind energy does.

<> Concentrated ore is very rare, so huge volumes of waste are created in providing the fuel.

<> Curiously, because of the thin film technology (thousandths of an inch), solar photovoltaic has a higher energy density.

<> Costs quoted (1.8 cent to 2.2 cents per kilowatt hour) are operating (that is, marginal) cost only, that is, fuel, maintenance, and personnel, and omit R & D, plant amortization, end-of-life decommissioning, and ultimate spent fuel storage costs. <3> Fully costed, it is our most expensive electrical energy source, at 6-10 cents per kilowatt hour. New reactor designs are expected to come in under 5 cents per kilowatt hour.

<> 90% of the uranium is imported, which is not consistent with national security. (We do have large domestic reserves that are not in large-scale production.)

<> The new technology is still questioned under conditions like terrorist attack. Unlike other methods of generating electricity there is no totally fail-safe mode for radioactive material.

<> Nuclear-produced electricity is less than 3% of our total energy consumption.

<> Nuclear produced electricity cost of 2 cents per kilowatt hour ignores plant amortization cost.

A couple of the points are relatively true for us, because of the import share, that is, we get to export much of the pollution, and the main suppliers, Canada and Australia, are secure allies.


The Cons

The major negatives presented by its opponents are:

<> Spent fuel storage will always be a problem.

<> Radioactive uranium hexafluoride, left over from the concentrating process in large quantities, also has to be stored.

<> Uranium 235, which is fissionable without concentration, is not abundant.

<> Plutonium can be used to make bombs, and therefore vastly increases the security risk.

<> Plutonium is an extremely hazardous and deadly poison.

<> Nuclear reactors are inherently unsafe, and if we have a lot of them, another Chernobyl will be inevitable.


A careful examination of these claims reveals that:

<> Technological advances have greatly reduced the amount of spent fuel relative to early days, and there is promise for accelerator transmutation to further mitigate the storage problem. "Integral fast reactors", now forbidden, produce much less waste with a half-life of about 500 years versus more than 10,000 years for conventional light water reactors (LWRs).

<> U238 is relatively abundant and the technology to concentrate it for reactor fuel is mature.

<> Using "fast" reactors we do not need U235.

<> There are three isotopes of plutonium, and the mix produced by breeder reactors, without complex and expensive further processing, is not "weapons grade".

<> The "advanced fast reactor" consumes rather than producing plutonium.

<> Barring direct inhalation of particles (which are heavy), plutonium is about as poisonous as lead.

<> Modern reactors are safer than most things we do in life - much safer than flying, or mining coal, for example.


The Real Issues

On balance, probably the most telling issues are:

<> At the end of the day we are dealing with radioactive materials, which pose both short- and long-term risks, and which have to be stored for millennia.

<> Exporting our pollution to the fuel source countries is not a very nice way to solve a problem.

<> If fully costed, nuclear energy is not now cost competitive. <2> (See section 4 below).

<> Greatly increasing the amount of plutonium around will inevitably raise security risks. Plutonium is already being smuggled. <1> (Note, this point is a negative for conventional reactors, but a positive for Integral Fast Reactors [IFRs] <4>.)

<> We have renewable alternatives that have none of these drawbacks.

<> Yucca Mountain will be full by 2020, and we will need to develop new storage, starting soon, or develop alternatives to long-term storage.

<> When full the storage facility becomes in effect a potential "plutonium mine", and we can't be sure it will be safeguarded for millennia.

<> Just to get to ten quads of nuclear power for the USA, assuming 1,000 megawatt plants, would require about 350 new plants, including replacement of the present 104, or an average of seven per state. The NIMBY prospect is considerable to say the least.

<> The proponents of new fail safe "pebble bed" reactors note that they are modular and could be built as 100 megawatt plants for local distribution. Does anyone want perhaps 2,000 or so sources of radioactive material to regulate and control? <1>


Resource Depletion

Some people point out that there is not enough Uranium reasonably available in the earth's crust to support much world growth in nuclear power, without facing another declining resource in a few decades. Again this is a false objection. There are 433 active reactors (excluding shipboard propulsion units) operating in the world today, with a combined capacity of about 350 gigawatts electric (GWe). They can generate about ten quads of electricity per year. Argonne Labs estimates available Uranium as 3000 quads. If we tripled world nuclear capacity between now and 2030, (unlikely), and then ran flat, that would carry us to 2110. In addition we have three times as much thorium, which can be upgraded to fissile uranium in nuclear reactors, so even with major growth of present technology reactors we would be good for two centuries or so.

However present conventional reactors only consume about 1% of the fuel, or perhaps 2% after upgrading. The "Integral Fast Reactor" (IFR) <4> would consume most of the fuel, and therefore stretch the available Uranium to 300,000 quads. Even with vastly expanded world consumption we have at least several centuries of fuel.

NB:- The HTML version has a graph here. See http://www.energypulse.net/centers/article/article_display.cfm?a_id=839


NB:- The Integral Fast Reactor (IFR) is also inherently safer in every respect than conventional reactors but IFR design was suspended in 1994 as a result of rather hysterical efforts by ill-informed anti-nuke activists who considered it to be a type of fast breeder reactor and open-ended source of near weapons grade plutonium. An even less informed House suspended development over the objections of a better-informed Senate.


Electricity Cost

Fully costed, nuclear generated electricity today costs from 6 to 10 cents per kilowatt hour, not competitive with coal or natural gas. However the main component of that cost is plant amortization at 5 to 7 cents per kilowatt hour. Most of our fleet of nuclear plants was built in the 1970s and is now approaching the end of the 30-year initial amortization period. About seven plants have already been re-licensed for a longer useful life (now fifty years), and several more have applied for re-licensing. After amortization, the cost of electricity for these plants will drop to about 2 cents per kilowatt hour, a cost that makes electricity almost free, and that no other source of electricity can compete with. Experts feel that with sound maintenance, the lifetime of a nuclear plant can be near "forever". Of course, this means that nuclear energy consumers, over the last thirty years have paid for very cheap energy for their progeny, an unusual and certainly unintentional act of altruism.

This point raises the question of cost for electricity from new nuclear plants. There are several ways of keeping such costs competitive. The first and most obvious is that operators of present plants will simply average their cost from new and fully amortized plants. Next, the high cost from numerous existing plants derived from huge cost overruns during construction, often due to regulatory delays. The initial cost of new plants can be expected to be lower, and indeed fully costed electricity from new plants is projected as under 5 cents per kilowatt hour. If global warming is finally taken seriously in the USA (which now seems likely), and a carbon trading scheme is introduced, nuclear plants should be allowed to trade carbon credits, thus providing an income stream to offset amortization. Finally, if plant life is taken to be very long, as now seems certain, amortization can be spread over 50 or maybe even 100 years. With all of these possibilities, new nuclear power will certainly be competitive with fossil fuels even at today's prices, and fossil fuel prices will only rise.

All of the above ignores the fact that nuclear R&D has been paid for by the taxpayer. R&D for, eg, gas turbines is paid for by the manufacturer and that cost is passed along in price to the customer. Historically, most of the nuclear R&D led to atom bombs and reactors for nuclear submarines so having the taxpayer pay was appropriate. That is no longer the case, but given the strength of the precedent nothing is likely to change. We can't know the real cost of nuclear energy unless the industry pays its own R&D costs. We should consider such already "sunk" R&D cost as a gift to future generations, another little piece of altruism, that may offset some of the other problems we are leaving them.


No Nukes!

The anti-nuclear folk correctly point out that we can choose to phase out nuclear energy without any significant negative impact on our economy. We do not have a major American processing industry. The rest of the world will still provide a market for Australia and Canada. We will still be a small market for fuel for naval reactors and for medical and industrial isotopes. Since nuclear provides less than 3% of the energy we consume, since it does have some real drawbacks, and since there are better, lower cost alternatives, why bother with it? For sure it does not make sense to expand subsidization <3> of a controversial energy source. With nuclear's subsidies, wind/solar/hydrogen would be competitive, and is much more desirable.


Reality Check

That said, let's consider reality. As natural gas and petroleum availability go into decline, and as the hydrogen economy develops, increasing electricity demand, nuclear will start to look more and more attractive. Resistance on the part of lawmakers is already dropping. The National Energy Policy Development Group (NEPDG), in their May 2001 report made this recommendation: "In the context of developing advanced nuclear fuel cycles and next-generation technologies for nuclear energy, the United States should reexamine its policies, to allow for research, development and deployment of fuel conditioning methods (such as pyroprocessing) that reduce waste streams and enhance proliferation resistance". They were referring to the Integral Fast Reactor (IFR). In fact there is now a consortium of ten countries, led by Argonne Labs of the USA, to define and develop the "fourth generation" nuclear reactor, dubbed the "Advanced Fast Reactor", (AFR) <6> a rebirth, with improvements of the IFR for which development was abandoned in 1994. It is expected that the first AFRs will go into service by 2030, and when petroleum does go into decline, that schedule is likely to be advanced. Argonne is also leading the Congressional Advanced Reactor Hydrogen Project, designing the Next Generation Nuclear Plant, and developing technology to prolong the working life of present reactors.

An alternative new reactor design, the helium cooled "pebble bed" reactor (PBR) <7> is also in development, with units expected to be in service in China <8> and South Africa in the time frame of 2008 to 2012. Actually PBRs are not new. The first such reactor was operated in Germany for several years starting in the early 1980s. The PBR is claimed to be inherently fail-safe, in that overheating of the core forces passive shutdown, but there was a failure in the fuel feed to the German unit that resulted in the release of a plume of radioactive material, and led the German government to permanently shut the unit down. This specific failure mode could be prevented by design change. South Africa has plans to build at least ten PBRs for domestic use, and to build up to twenty per year small modular "plug and play" units for export. China is targeting 300 gigawatts electric of PBR capacity by 2050. South Korea is also in the planning stages of adding PBR capacity. Even Serbia has now announced plans to build a new reactor. Nuclear is at the beginning of a major comeback, especially in less developed countries (undoubtedly with USA involvement), but before long in the USA also, like it or not.


Sell the Benefits.

What are the benefits and drawbacks of the new designs?

PBR: The major benefits claimed are:

<> They are operationally fail-safe by design.

<> Burn rate can be readily adjusted enabling accommodation of peak loads.

<> They are continuously fueled obviating periodic prolonged shutdown for refueling.

<> They are modular and can be built and operated in sizes as small as 10 megawatts.

<> They can be delivered as operational "plug and play" modules and put together like legos, making them practical even for LDCs.

<> They are low initial cost.

<> When prefab'd modules become available, time to commissioning may be as short as two years.


PBR: The drawbacks are:

<> They burn fuel inefficiently like conventional light water reactors (LWRs), meaning large amounts of long half-life radioactive waste production.

<> They are modular, and can be delivered in plug and play modules.

<> They don't strictly require a containment housing.

<> Given the last two points, and inevitable delivery to countries with low levels of technology, controls and maintenance abilities, they will be disasters waiting to happen in some cases.

Only the inefficiency drawback is a problem in the USA.


AFRs: The major benefits claimed are: <4>

<> no production and build-up of plutonium - they are closed loop with an integrated fuel reprocessing (pyroprocessing ) stage, so the plutonium produced is ultimately consumed.

<> short-term management of plutonium - the in-process plutonium produced is not accessible as it never leaves a highly radioactive environment.

<> disposition and long-term management of plutonium - they can burn existing plutonium stockpiles, especially that reclaimed from weapons.

<> other proliferation concerns - they ultimately eliminate the "plutonium mine".

<> long-term waste management - they produce much less radioactive waste, burning the long half-life actinides and leaving short (less than 500 year) half-life residue.

<> environmental effects - much less uranium ore processing per year.

<> resource conservation and long-term energy supply - more than seventy times the energy recovery of conventional reactors.

<> safety - automatic shutdown with thermal sink reserve to ensure core cooling in case of failure in the heat exchanger cycle.

<> refueling shutdown - they are expected to run for up to forty years on a single fuel charge.

<> constant output - base-load supply that wants to operate 24 hours per day and that provides a balance for variable renewables electricity generation. In the hydrogen economy this is a further advantage, because low priced night-time production can be used for hydrogen generation.


AFRs: The drawbacks are:

<> high initial cost and therefore high electricity cost. This drawback can be offset for the first several reactors built by charging for disposal of existing plutonium stockpiles. They should be given credit for elimination of such hazardous waste. See also section 4 above.

<> The first IFR was designed with a liquid sodium cooling bath, and a sodium/water heat exchanger. Everyone knows about the danger of sodium-water contact, and a staged film of such large-scale contact would be a major selling point for anti-nuke activists. New designs are evaluating sodium/helium and lead-bismuth/water heat exchangers. Russia already has a lot of experience with the latter.


Conclusions

Declining availability of natural gas and petroleum are going to shift a major portion of our energy burden to electricity. In response we will certainly turn to coal, renewables and nuclear. If the decline is sharp, which is very likely for natural gas, we will not be able to respond quickly enough on the supply side, especially given the very long permitting, building and commissioning times for nuclear (up to ten years today). Pebble Bed Reactors (PBRs) hold out promise to reduce this time to perhaps 2-3 years before 2010. When nuclear becomes again acceptable, we are likely to build PBRs for some years, while we accelerate development of Advanced Fast Reactors (AFRs). Before 2030 AFRs will almost undoubtedly be the reactor of choice. While nukes will always have inherent danger, AFRs have the promise of eliminating plutonium stockpiles, and can thus, on balance, make the world a safer place. There is still a need to overcome poorly informed and emotional resistance.

References:

1 http://www.newscientist.com/news/news.jsp?id=ns9999782

2 http://www.antenna.nl/wise/uranium/ for a lot of info the nuclear industry does not want to tell you.

3 Jerry Taylor, the director of natural resource studies at the Cato Institute, a libertarian think tank, notes: "Were it nor for government subsidies, there wouldn't be one nuclear power plant in this country".
4 http://www.anlw.anl.gov/anlw_history/reactors/ifr.html
5 http://www.nationalcenter.org/NPA378.html
6 http://www.aps.org/units/fps/newsletters/2002/april/a1ap02.cfm
7 http://en.wikipedia.org/wiki/Pebble_bed_reactor
8 http://www.grist.org/news/daily/2004/09/03/china/index.html


Copyright 2002-2004, CyberTech, Inc. All rights reserved.

http://www.energypulse.net/centers/article/article_display.cfm?a_id=839


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