A Step Farther Out

by Jerry Pournelle

  Since the above was written there have been some changes. First, the payments for Arab oil have gone out of sight: when your energy policy is to pay out $50 billion a year to the Arabs, you can afford almost any alternative.

  Secondly, the Soviets have offered cooperation, sending Basov and Rudikov over to show us their results.

  Thirdly, in all areas of fusion research there have been some unexpected results; some breakthroughs, other things just going better than expected.

  As a result, a number of fusion experts now believe we could have a working commercial fusion-powered generator by 1995, possibly a shade earlier.

  It doesn't matter, though: at present levels of funding we will not have a reactor before 2000. We may never-get one: the fusion research budget was deeply cut by the Carter administration, and the level-of-effort funding now supplied does not make the experts hopeful.

  Moreover, the Soviet offers of cooperation were treated rather strangely: although they declassified the information and brought it to us, we classified it, although from whom we are keeping it secret escapes me. Nor were the Soviet experts given the red-carpet treatment: Basov was not even invited to Washington. I have been told that had he said fusion would not work he would have received the red-carpet treatment; I have no confirmation of this, nor do I know of any reason why the Carter administration would prefer that fusion research fail.

  However: if we're to save ourselves from our present policy of selling the country to the Shah of Iran and the Sheik of Araby on the installment plan, we need some "Manhattan Project" type research; and instead we are slashing the research budgets to the bone and beyond.

  [JEP Spring 1978]

  Cheer up. First, we don't need fusion; at least not immediately. There are other ways to power our industrial civilization; other ways to spark the Third Industrial Revolution as described by me and by Harry Stine who coined the term. We can all get rich even if controlled fusion never works. That ought to be good news. Here are some methods.

  First, my favorite, the ocean-thermal system, which makes use of the temperature difference between warm surface water and cold bottom water. There's more than enough power in the Tropics to run the world, the Sun renews it constantly, and we know it will work because a working plant was built in 1928. However, my engineering friends tell me that's the hard way; and we aren't likely to have operating ocean-thermal systems before the year 2000 anyway.

  So what are some other ways? Here's where I get into trouble. The easiest way of all is one we have now good old reliable (average nuclear plant operates 9 mos. each year; fossil, 8.2 mos. each year) nuclear fission. It already works, and we've already mined enough potential fuel to last us several hundred years; moreover, there's enough U-238 in ordinary rock to operate the world high-energy economy for millennia.

  Alas, that takes breeder reactors, and they're controversial. They make plutonium, and everyone knows that plutonium is "the most toxic material known to man." Ralph Nader has told us so. Of course Ralph Nader is also the man who, with fanfare, bought a manual rather than an electric typewriter "to conserve energy." My electric uses the electricity generated by about a quarter of a cup of oil each year; if everybody, all 230 million of us, had an electric typer going they'd consume a few thousand barrels of oil annually: not very much in an economy that measures oil consumption in millions of barrels a day. Maybe we ought to take a closer look at some of the other things Mr. Nader says. His heart's in the right place, but he doesn't seem to do much quantitative thinking.

  Toxicity of plutonium compared to other substances is shown in figure 33. Now we don't spread much botulin around the landscape, but we do spray crops with arsenic trioxide; in fact, we today import 10 times as much arsenic as we'd have nuclear wastes if the entire US electric system were run on nuclear fission. Now I keep telling myself that I am NOT going to write a paper in defense of nuclear fission power; that it's a political matter; but dammit, at least the public debates ought to make sense. It's one thing seriously and soberly to debate the advantages and disadvantages of fission over fossil fuel; but it's quite another to have such an important issue decided by mythology and demonology.

  One last thing, then: nuclear wastes are radioactive. There. That ought to end the debate. Surely no one wants "nuclear pollution." If I sound sarcastic, my apologies; somebody really and truly said that to me not long ago. Meant it, too; and she was an important political party official.

  So let's look at radioactivity in quantitative terms. Figure 34 shows the dose in millirems (thousandths of a rem) received by each US citizen on the average. Further, let's add a couple bits of information: of the 24,000 survivors exposed to 140 rems (140,000 mrem) at Hiroshima-Nagasaki, fewer than 200 died of cancer. The probability of developing cancer from radiation exposure is about 0.018% per rem (not mrem).

  As to storage: it's true that at present most nuclear wastes are stored as liquids, hundreds of thousands of gallons of them; they leak from time to time. But liquid-storage was never intended to be anything but a temporary expedient; it is possible to take those wastes and make them part of glass blocks, and only legal, not technical, barriers have prevented that.

  Glass is a very stable substance. It is practically eternal. If all the nuclear wastes accumulated from the Manhattan

  __________

  Figure 33

  TOXICITY OF VARIOUS

  SUBSTANCES

  Lethal doses per spoonful

  Arsenic trioxide 50

  Botulinus toxin 125,000,000

  Plutonium oxide (ingested)* 0.5

  "metallic Pu is never employed in reactors.

  __________

  Figure 34

  SOURCES OF RADIATION RECEIVED

  BY AVERAGE US CITIZEN (ANNUAL)

  __________

  Project to present—including those resulting from weapons manufacture, which created more wastes than the power program—were solidified, the resulting block would be somewhat less than 60 feet on a side. If the entire country ran off nuclear power, all the wastes from now to the year 2020 could be contained in a block less than 100 feet on a side.

  And the block could be stored under a superdome-like structure in the Mojave Desert for want of anywhere else to put it. Build a concrete dome; put in the wastes; and surround it all with a chainlink fence and the warning sign "IF YOU CLIMB THIS FENCE YOU WILL DIE." Or guard the area. Or both. Eventually we will have either a use for the wastes or a permanent storage area such as geologically stable salt mines; but certainly the Mojave would hold them for a couple of hundred years if need be.

  At this point in my lectures someone generally says, loudly, "sabotage!" Nuclear plants are vulnerable to that, aren't they? Well, yes; but not very. The 4 foot steel and concrete containment is designed to take an aircraft crashing into it without rupture. Anyone stealing nuclear fuels for terror purposes has set himself a pretty suicidal task, will need vast technological resources, and won't get very many people very fast—what's the point of threatening people with an increased probability of cancer 15 years after you set off your infernal device?

  Oh, sure: in theory a respectable bomb can be made from nuclear fuels, and certainly one could refine spent fuel to get plutonium: but to do that, in secret, requires the resources of a government, and governments don't need to steal nuclear wastes. Uranium can be bought on the open market, and you can breed weapons-grade stuff in a research reactor—as India did. Note well: of all nations that have The Bomb (including several such as Israel and South Africa which probably do but which have not announced it) not one used power reactors in the weapons manufacture.

  The fact is, if you're in the terror business, kidnapping is simpler; or if you've a pash to be suicidally spectacular, try crashing a hijacked jet into the Rose Bowl on New Year's Day.

  In other words, if we're going to debate power policy? let's do it right, with comparisons of risks, not scare statements. I'm willing; if you're interested, my lecture fees aren't too high, and yo
u can reach me care of the publisher. Be prepared to pay expenses and a reasonable fee.

  This has taken us a long way from fusion, hasn't it? No; because fusion, like other power systems, needs to be discussed in context. I will not recommend fusion research as a magic remedy for the world's ills.

  I do recommend it, though. For all its disadvantages, fusion will be, if it works, the power system of the future.

  First, it's very fuel-efficient. If we can extract all the energy from our D, we get an average of about 100,000 kW-hr/gram, which is 4 times the energy per gram obtained by fission reactors, and ten million times the energy/gram from burning fossil fuels. A few thousand metric tons of D each year could power the world.

  Second, the fuel's not hard to get. There is about one atom of D for every 6,000 atoms of ordinary hydrogen. The world's D supply could come from under fifty plants with water intake valves ten to twenty feet in diameter. By world's energy supply, I mean the equivalent of some 20 billion barrels of oil a day—more than enough to let Ralph Nader have a new Selectric.

  Third, we can never run out of D. There are billions of cubic kilometers of water on this Earth, and at a cubic kilometer each year we'd be able to run a long time; nor would we, as I've heard someone say, "lower the oceans"; at least not more than an atomic diameter or two.

  Fourth, fusion is certainly preferable to fission: the waste-management problem is much simpler. There are fewer long-term radioactive wastes to worry about. Although we can and will (and already have) shipped tons of plutonium around without anyone being injured, the stuff is unpleasant, and we'd be better off without it even if fusion won't eliminate all nuclear wastes.

  So how do we do it? There are two major theories on how fusion plants might work, first, remember that the goal is extremely high temperatures and pressures. You can't contain them in a material object, because either your reaction melts your container, or your container cools off the D and prevents the reaction. Thus non-material confinement systems, which means in practice Magnetic Confinement. The lion's share of all fusion research goes to that. The problems are hairy: both engineering and scientific questions remain unanswered.

  The equipment is huge, complex, and (need I say it?) costly. There are blind alleys. We had stellerators, and magnetic rings, and various kinds of pinch-bottles, and every one of them failed. It isn't that they weren't worth building, understand; we have learned a lot about magneto-hydro-dynamic stability of plasmas (there's a buzz phrase for you). The current approach is a device called a tokamak, and if you need to know more about those go to your nearest library. Magnetic confinement isn't expected to produce fusion neutrons for another ten years, and few think it will, even in the laboratory, produce more power than it consumes before 1990. It got plenty of funding prior to the Carter administration.

  The second approach is called Inertial Confinement. This consists of taking small pellets of D, or a D and T mixture, and zapping them with lots of energy. The zapping has to be done just right. If you're not careful, too much zapping energy gets inside the pellet and tends to disrupt it before fusion can take place. There are other failure mechanisms, such as lopsided zaps, and not enough zap-power.

  Inertial confinement has this advantage: it is pretty certain to work That is, the problems are more engineering than scientific. It may never work usefully, but it almost has to work if we get the geometry right and shoot enough power to the pellets. It has a second advantage: the equipment is much cheaper (for laboratory demonstration reactors; not necessarily for a working commercial power generating system). Thus Inertial Confinement gets about 10% of the fusion research budget.

  There are two branches of Inertial Confinement: laser (photon) bombardment, and particle bombardment. Of the research money in inertial confinement, 90% or more goes to laser systems. There's a reason for that: laser bombardment just may have produced fusion already. There was some fanfare a few years ago when KMS Inc., a private company, seemed to have obtained fusion neutrons. There's still some question about just what KMS did or did not achieve, but most fusion people believe that laser bombardment will eventually work out. Right now they're looking at different kinds of lasers, and may have to invent a new one (called Brand X Laser) which will zap the pellet with enough energy, yet won't penetrate the pellet too fast.

  [In November, 1977, the Soviet Nobel laureate Nikolai Basov told a conference in Fort Lauderdale that he had achieved a breakthrough: by exciting the pellets with soft x-rays prior to zapping them with a laser, he had managed to get scientific breakeven; that he had bettered the so-called Lawson Criterion by a factor of five.

  There was very little about Basov's announcement in the popular press; I don't know why, because it's a rather exciting discovery. There was some doubt expressed by US research workers: did Basov get the proper temperatures? As I write this the Lawrence Radiation Laboratories at Livermore are said to be checking out Basov's results, but the whole program including exactly what Basov told us is classified, so I can report no more than that.

  Laser fusion research, like all other fusion research, suffered a budget cut in the first years of the Carter administration; according to the Soviets it is a very promising line of development. JEP Spring 1978]

  Finally, there's electron-beam inertial confinement, which is only carried on at Sandia Laboratories (a nonprofit corporation) in Albuquerque, New Mexico. I visited the labs recently, and came away a believer.

  At the time of my visit the Sandia electron-beam fusion program was funded at about $5 million a year; nowhere near enough, in my judgment Electron bombardment may just be the way to go.

  They've already achieved fusion with this method. Not breakeven; but both US and Soviet experiments have definitely produced several billion fusion neutrons. The Soviets are attempting to cooperate with the US, but once again, when Rudikov came to the US to tell his results, we classified his talk However, it's definite that he reported obtaining fusion neutrons, because that was announced in the Soviet popular press. (Evidently the Soviet Union isn't interested in keeping it a secret from whomever we are keeping in the dark.)

  Electron-beam fusion has always been the least-funded of the fusion research programs, in part because it doesn't need as much money.

  I have watched a man spend four billion dollars an hour on electricity. It made him unhappy. He wanted to spend a trillion an hour. It happened at Sandia labs: they were zapping a pellet with electrons. Of course they didn't spend four billion bucks an hour for very long: a few nano-seconds, to be exact, so the total cost of the electricity was a few dollars; but if they could have kept it up!

  The Sandia equipment is impressive. It's also massive, as you'd expect, considering that they handle millions of volts. To get that they have to charge up enormous capacitance systems. Sirens wail, red lights flash, needles crawl across dials, just like in a good science fiction movie, and finally the technician puts his fingers in his ears. I didn't, in time, and the noise of a couple of mega joules arcing into a target is not easily forgotten.

  Even so, it's not enough. That's what costs the money: building equipment that will handle those voltages without breakdown (and breakdowns are spectacular around there; I didn't see one, but I saw insulators the size of a desk with inch-deep gouges burned into them). Then there's the triggering problem: that system has to discharge all its energy at the right time, and the right time is measured in billionths of a second. It's amazing that they can do it; but they can. I saw it done. Incidentally, the voltage amplifier systems they use are called Marx generators, which gives rise to a number of puns, political jokes, etc., and worse; when they were ready to fire someone shouted "Harpo's ready!" and another man said "Stand by to fire Groucho." Then there was the zap! and a million joules flowed for a few nano-seconds.

  Mega-joules. A joule is 107 ergs. I was duly impressed until we got to talking after the experiment. The reason they don't have fusion yet is they just can't pump enough power through the system fast enough, but don't get d
iscouraged. The amount of power needed isn't so very large after all. In fact, we calculated that a Sears Lifetime Battery contains about 4 mega-joules, and if we could just discharge that sucker in a couple of nano-seconds we'd have fusion.

  They're building a system that they expect will do just that.

  At the moment Sandia hopes to be at the squash court stage by 1983: that is, by then they hope to have proved that electron bombardment inertial confinement fusion will work and can, with a lot more skull sweat and good engineering design, eventually be part of a useful electric power system.

  They're doing that on five million dollars a year. This is the system I mentioned in the beginning of this article. I think it deserves more money, because with more money they may get to the squash court before 1980. They don't promise it, but then they don't need much more money either; a doubling of their present five million annually would not only let them build more hardware faster, but also let them coordinate some theoretical work going on around the country, and bring in other scientists as consultants.

  So: if you're in a mood to write your Congresscritter about energy problems, you might mention that here's a slot where, in my considered judgment, a few million bucks will do a lot of good. Please don't support this because you think it will get us to the year 2000; it's unlikely. Don't support it because you think it will eliminate our need for nasty plutonium. Do it as a present for your children; do it because we could use some decent national goals, and cheap clean fusion power is one of the better gifts the US could offer the world.