Posted on October 23rd, 2012 No comments
ARPA-E, or the Advanced Research Projects Agency – Energy, is supposed to be DOE’s version of DARPA. According to its website, its mission,
…is to fund projects that will develop transformational technologies that reduce America’s dependence on foreign energy imports; reduce U.S. energy related emissions (including greenhouse gasses); improve energy efficiency across all sectors of the U.S. economy and ensure that the U.S. maintains its leadership in developing and deploying advanced energy technologies.
So far, it has not come up with anything quite as “transformational” as the Internet or stealth technology. There is good reason for this. Its source selection people are decidedly weak in the knees. Consider the sort of stuff it’s funded in the latest round of contract awards. The people at DARPA would probably call it “workman like.” H. L. Mencken, the great Sage of Baltimore, would more likely have called it “pure fla fla.” For example, there are “transformational” systems to twiddle with natural gas storage that the industry, not exactly short of cash at the moment, would have been better left to develop on its own, such as,
Liquid-Piston Isothermal Home Natural Gas Compressor
Chilled Natural Gas At-Home Refueling
Superplastic-Formed Gas Storage Tanks
There is the ”transformational” university research that is eye-glazingly mundane, and best reserved as filler for the pages of obscure academic journals, such as,
Cell-level Power Management of Large Battery Packs
Health Management System for Reconfigurable Battery Packs
Optimal Operation and Management of Batteries Based on Real Time Predictive Modeling and Adaptive Battery Management Techniques.
There is some “groundbreaking” stuff under the rubric of “build a better magnet, and the world will beat a pathway to your door.”
Manganese-Based Permanent Magnet with 40 MGOe at 200°C
Rare‐Earth‐Free Permanent Magnets for Electrical Vehicle Motors and Wind Turbine Generators: Hexagonal Symmetry Based Materials Systems Mn‐Bi and M‐type Hexaferrite
Discovery and Design of Novel Permanent Magnets using Non-strategic Elements having Secure Supply Chains
…and so on. Far be it for me to claim that any of this research is useless. It is, however, also what the people at DARPA would call “incremental,” rather than transformational. Of course, truly transformational ideas don’t grow on trees, and DARPA also funds its share of “workmanlike” projects, but at least the source selection people there occasionally go out on a limb. In the work funded by ARPA-E, on the other hand, I can find nothing that might induce the bureaucrats on Secretary Chu’s staff to swallow their gum.
If the agency is really serious about fulfilling its mission, it might consider some of the innovative ideas out there for harnessing fusion energy. All of them can be described as “high risk, high payoff,” but isn’t that the kind of work ARPA-E is supposed to be funding? According to a recent article on the Science Magazine website, the White House has proposed cutting domestic fusion research by 16%to help pay for the U.S. contribution to the international fusion experiment, ITER, under construction in Cadarache, France. As I’ve pointed out elsewhere, ITER is second only to the International Space Station as the greatest white elephant of all time, and is similarly vacuuming up funds that might otherwise have supported worthwhile research in several other countries. All the more reason to give a leg up to fusion, a technology that has bedeviled scientists for decades, but that could potentially supply mankind’s energy needs for millennia to come. Ideas being floated at the moment include advanced fusor concepts such as the Bussard polywell, magneto-inertial fusion, focus fusion, etc. None of them look particularly promising to me, but if any of them pan out, the potential payoff is huge. I’ve always been of the opinion that, if we ever do harness fusion energy, it will be by way of some such clever idea rather than by building anything like the current “conventional” inertial or magnetic fusion reactor designs.
When it comes to conventional nuclear energy, we are currently in the process of being left in the dust by countries like India and China. Don’t expect any help from industry here. They are in the business to make a profit. There’s certainly nothing intrinsically wrong with that, but at the moment, profits are best maximized by building light water reactors that consume the world’s limited supply of fissile uranium 235 without breeding more fuel to replace it, and spawn long-lived and highly radioactive transuranic actinides in the process that it will be necessary to find a way to safely store for thousands of years into the future. This may be good for profits, but it’s definitely bad for future generations. Alternative designs exist that would breed as much new fuel as they consume, be intrinsically safe against meltdown, would destroy the actinides along with some of the worst radioactive fission products, and would leave waste that could be potentially less radioactive than the original ore in a matter of a few hundred years. DOE’s Office of Nuclear Energy already funds some research in these areas. Unfortunately, in keeping with the time-honored traditions of government research funding, they like to play it safe, funneling awards to “noted experts” who tend to keep plodding down well-established paths even when they are clearly leading to dead ends. ITER and the International Space Station are costly examples of where that kind of thinking leads. If it were really doing its job, an agency like ARPA-E might really help to shake things up a little.
Finally, we come to that scariest of boogeymen of “noted experts” the world over; cold fusion, or, as some of its advocates more reticently call it, Low Energy Nuclear Reactions (LENR). Following the initial spate of excitement on the heels of the announcement by Pons and Fleischmann of excess heat in their experiments with palladium cells, the scientific establishment agreed that such ideas were to be denounced as heretical. Anathemas and interdicts rained down on their remaining proponents. Now, I must admit that I don’t have much faith in LENR myself. I happened to attend the Cold Fusion Workshop in Sante Fe, NM which was held in 1989, not long after the Pons/Fleischmann bombshell, and saw and heard some memorably whacky posters and talks. I’ve talked to several cold fusion advocates since then, and some appeared perfectly sober, but an unsettlingly large proportion of others seemed to be treading close to the lunatic fringe. Just as fusion energy is always “30 years in the future,” cold fusion proponents have been claiming that their opponents will be “eating crow in six months” ever since 1989. Some very interesting results have been reported. Unfortunately, they haven’t been reproducible.
For all that, LENR keeps hanging around. It continues to find advocates among those who, for one reason or another, aren’t worried about their careers, or lack respect for authority, or are just downright contrarians. The Science of Low Energy Nuclear Reactions by Edmund Storms is a useful source for the history of and evidence for LENR. Websites run by the cold fusion faithful may be found here and here. Recently, stories have begun cropping up again in “respectable” mags, such as Forbes and Wired. Limited government funding has been forthcoming from NASA Langley and, at least until recently, from the Navy at its Space and Naval Warfare Systems Command (SPAWAR). Predictably, such funding is routinely attacked as support for scientific quackery. The proper response to that from the source selection folks at ARPA-E should be, “So what?” After all,
ARPA-E was created to be a catalyst for innovation. ARPA-E’s objective is to tap into the risk-taking American ethos and to identify and support the pioneers of the future. With the best research and development infrastructure in the world, a thriving innovation ecosystem in business and entrepreneurship, and a generation of youth that is willing to engage with fearless intensity, the U.S. has all the ingredients necessary for future success. The goal of ARPA-E is to harness these ingredients and make a full-court press to address the U.S.’s technological gaps and leapfrog over current energy approaches.
The best way to “harness these ingredients and make a full-court press” is not by funding of the next round of incremental improvements in rare earth magnets. Throwing a few dollars to the LENR people, on the other hand, will certainly be “high risk,” but it just might pan out. I hope the people at ARPA-E can work up the minimal level of courage it takes to do so. If the Paris fashions can face down ridicule, so can they. If they lack the nerve, then DOE would probably do better to terminate its bad imitation of DARPA and feed the money back to its existing offices. They can continue funding mediocrity just as well as ARPA-E.
Posted on July 7th, 2012 No comments
It’s been over a century since Max Planck came up with the idea that electromagnetic energy could only be emitted in fixed units called quanta as a means of explaining the observed spectrum of light from incandescent light bulbs. Starting from this point, great physicists such as Bohr, de Broglie, Schrödinger, and Dirac developed the field of quantum mechanics, revolutionizing our understanding of the physical universe. By the 1930′s it was known that matter, as well as electromagnetic energy, could be described by wave equations. In other words, at the level of the atom, particles do not behave at all as if they were billiard balls on a table, or, in general, in the way that our senses portray physical objects to us at a much larger scale. For example, electrons don’t act like hard little balls flying around outside the nuclei of atoms. Rather, it is necessary to describe where they are in terms of probability distributions, and how they act in terms of wave functions. It is impossible to tell at any moment exactly where they are, a fact formalized mathematically in Heisenberg’s famous Uncertainty Principle. All this has profound implications for the very nature of reality, most of which, even after the passage of many decades, are still unknown to the average lay person. Among other things, it follows from all this that there are two basic types of elementary particles; fermions and bosons. It turns out that they behave in profoundly different ways, and that the idiosyncrasies of neither of them can be understood in terms of classical physics.
Sometimes the correspondence between mathematics and physical reality seems almost magical. So it is with the math that predicts the existence of fermions and bosons. When it was discovered that particles at the atomic level actually behave as waves, a brilliant Austrian scientist named Erwin Schrödinger came up with a now-famous wave equation to describe the phenomenon. Derived from a few elementary assumptions based on some postulates derived by Einstein and others relating the wavelength and frequency of matter waves to physical quantities such as momentum and energy, and the behavior of waves in general, the Schrödinger equation could be solved to find wave functions. It was found that these wave functions were complex numbers, that is, they had a real component, and an “imaginary” component that was a multiple of i, the square root of minus one. For example, such a number might be written down mathematically as x + iy. Each such number has a complex conjugate, found by changing the sign of the complex term. The complex conjugate of the above number is, therefore, x – iy. Max born found that the probability of finding a physical particle at any given point in space and time could be derived from the product of a solution to Schrödinger’s equation and its complex conjugate.
So far, so good, but eventually it was realized that there was a problem with describing particles in this way that didn’t arise in classical physics; you couldn’t tell them apart! Elementary particles are, after all, indistinguishable. One electron, for example, resembles every other electron like so many peas in a pod. Suppose you could put two electrons in a glass box, and set them in motion bouncing off the walls. Assuming you had very good eyes, you wouldn’t have any trouble telling the two of them apart if they behaved like classical billiard balls. You would simply have to watch their trajectories as they bounced around in the box. However, they don’t behave like billiard balls. Their motion must be described by wave functions, and wave functions can overlap, making it impossible to tell which wave function belongs to which electron! Trying to measure where they are won’t help, because the wave functions are changed by the very act of measurement.
All this was problematic, because if elementary particles really were indistinguishable in that way, they also had to be indistinguishable in the mathematical equations that described their behavior. As noted above, it had been discovered that the physical attributes of a particle could be determined in terms of the product of a solution to Schrödinger’s equation and its complex conjugate. Assuming for the moment that the two electrons in the box didn’t collide or otherwise interact with each other, that implies that the solution for the two particle system would depend on the product of the solution for both particles and their complex conjugates. Unfortunately, the simple product didn’t work. If the particles were labeled and the labels switched around in the solution, the answer came out different. The particles were distinguishable! What to do?
Well, Schrödinger’s equation has a very useful mathematical property. It is linear. What that means in practical terms is that if the products of the wave functions for the two particle system is a solution, then any combination of the products will also be a solution. It was found that if the overall solution was expressed as the product of the two wave functions plus their product with the labels of the two particles interchanged, or of the product of the two wave functions minus their product with the labels interchanged, the resulting probability density function was not changed by changing around the labels. The particles remained indistinguishable!
The solution to the Schrödinger equation, referred to mathematically as an eigenfunction, is called symmetric in the plus case, and antisymmetric in the minus case. It turns out, however, that if you do the math, particles act in very different ways depending on whether the plus sign or the minus sign is used. And here’s where the magic comes in. So far with just been doing math, right? We’ve just been manipulating symbols to get the math to come out right. Well, as the great physicist, Richard Feynman, once put it, “To those who do not know mathematics it is difficult to get across a real feeling as to the beauty, the deepest beauty, of nature.” So it is in this case. The real particles act just as the math predicts, and in ways that are completely unexplainable in terms of classical physics! Particles that can be described by an antisymmetric eigenfunction are called fermions, and particles that can be described by an symmetric eigenfunction are called bosons.
How do they actually differ? Well, for reasons I won’t go into here, the so-called exclusion principle applies to fermions. There can never be more than one of them in exactly the same quantum state. Electrons are fermions, and that’s why they are arranged in different levels as they orbit the nucleus of an atom. Bosons behave differently, and in ways that can be quite spectacular. Assuming a collection of bosons can be cooled to a low enough temperature they will tend to all condense into the same low energy quantum state. As it happens, the helium atom is a boson. When it is cooled below a temperature of 2.18 degrees above absolute zero, it shows some very remarkable large scale quantum effects. Perhaps the weirdest of these is superfluidity. In this state, it behaves as if it had no viscosity at all, and can climb up the sides of a container and siphon itself out over the top!
No one really knows what matter is at a fundamental level, or why it exists at all. However, we do know enough about it to realize that our senses only tell us how it acts at the large scales that matter to most living creatures. They don’t tell us anything about its essence. It’s unfortunate that now, nearly a century after some of these wonderful discoveries about the quantum world were made, so few people know anything about them. It seems to me that knowing about them and the great scientist who made them adds a certain interest and richness to life. If nothing else, when physicists talk about the Higgs boson, it’s nice to have some clue what they’re talking about.
Posted on April 17th, 2012 10 comments
The National Ignition Facility, or NIF, is a huge, 192 beam laser system, located at Lawrence Livermore National Laboratory in California. It was designed, as the name implies, to achieve thermonuclear ignition in the laboratory. “Ignition” is generally accepted to mean getting a greater energy output from fusion than the laser input energy. Unlike magnetic confinement fusion, the approach currently being pursued at the International Thermonuclear Experimental Reactor, or ITER, now under construction in France, the goal of the NIF is to achieve ignition via inertial confinement fusion, or ICF, in which the fuel material is compressed and heated to the extreme conditions at which fusion occurs so quickly that it is held in place by its own inertia.
The NIF has been operational for over a year now, and a two year campaign is underway with the goal of achieving ignition by the end of this fiscal year. Recently, there has been a somewhat ominous silence from the facility, manifesting itself as a lack of publications in the major journals favored by fusion scientists. That doesn’t usually happen when there is anything interesting to report. Finally, however, some papers have turned up in the journal Physics of Plasmas, containing reports of significant progress.
To grasp the importance of the papers, it is necessary to understand what is supposed to occur within the NIF target chamber for fusion to occur. Of course, just as in magnetic fusion, the goal is to bring a mixture of deuterium and tritium, two heavy isotopes of hydrogen, to the extreme conditions at which fusion takes place. In the ICF approach, this hydrogen “fuel” is contained in a tiny, BB-sized target. However, the lasers are not aimed directly at the fuel “capsule.” Instead, the capsule is suspended in the middle of a tiny cylinder made of a heavy metal like gold or uranium. The lasers are fired through holes on each end of the cylinder, striking the interior walls, where their energy is converted to x-rays. It is these x-rays that must actually bring the target to fusion conditions.
It was recognized many years ago that one couldn’t achieve fusion ignition by simply heating up the target. That would require a laser driver orders of magnitude bigger than the NIF. Instead, it is first necessary to compress, or implode, the fuel material to extremely high density. Obviously, it is harder to “squeeze” hot material than cold material to the necessary high densities, so the fuel must be kept as “cold” as possible during the implosion process. However, cold fuel won’t ignite, begging the question of how to heat it up once the necessary high densities have been achieved.
It turns out that the answer is shocks. When the laser generated x-rays hit the target surface, they do so with such force that it begins to implode faster than the speed of sound. Everyone knows that when a plane breaks the sound barrier, it, too, generates a shock, which can be heard as a sonic boom. The same thing happens in ICF fusion targets. When such a shock converges at the center of the target, the result is a small “hot spot” in the center of the fuel. If the temperature in the hot spot were high enough, fusion would occur. Each fusion reaction would release a high energy helium nucleus, or alpha particle, and a neutron. The alpha particles would be slammed to a stop in the surrounding cold fuel material, heating it, in turn, to fusion conditions. This would result in a fusion “burn wave” that would propagate out through the rest of the fuel, completing the fusion process.
The problem is that one shock isn’t enough to create such a “hot spot.” Four of them are required, all precisely timed by the carefully tailored NIF laser pulse to converge at the center of the target at exactly the same time. This is where real finesse is needed in laser fusion. The implosion must be extremely symmetric, or the shocks will not converge properly. The timing must be exact, and the laser pulse must deliver just the right amount of energy.
One problem in the work to date has been an inability to achieve high enough implosion velocities for the above scenario to work as planned. One of the Physics of Plasmas papers reports that, by increasing the laser energy and replacing some of the gold originally used in the wall of the cylinder, or “hohlraum,” in which the fuel capsule is mounted with depleted uranium, velocities of 99% of those required for ignition have been achieved. In view of the recent announcement that a shot on the NIF had exceeded its design energy of 1.8 megajoules, it appears the required velocity is within reach. Another of the Physics of Plasmas papers dealt with the degree to which implosion asymmetries were causing harmful mixing of the surrounding cold fuel material into the imploded core of the target. It, too, provided grounds for optimism.
In the end, I suspect the success or failure of the NIF will depend on whether the complex sequence of four shocks can really be made to work as advertised. That will depend on the accuracy of the physics algorithms in the computer codes that have been used to model the experiments. Time and again, earlier and less sophisticated codes have been wrong because they didn’t accurately account for all the relevant physics. There is no guarantee that critical phenomena have not been left out of the current versions as well. We may soon find out, if the critical series of experiments planned to achieve ignition before the end of the fiscal year are carried out as planned.
One can but hope they will succeed, if only because some of our finest scientists have dedicated their careers to the quest to achieve the elusive goal of controlled fusion. Even if they do, fusion based on the NIF approach is unlikely to become a viable source of energy, at least in the foreseeable future. Laser fusion may prove scientifically feasible, but getting useful energy out of it will be an engineering nightmare, dangerous because of the need to rely on highly volatile and radioactive tritium, and much too expensive to compete with potential alternatives. I know many of the faithful in the scientific community will beg to differ with me, but, trust me, laser fusion energy aint’ gonna happen.
On the other hand, if ignition is achieved, the NIF will be invaluable to the country, not as a source of energy, but for the reason it was funded in the first place – to insure that our nation has an unmatched suite of experimental facilities to study the physics of nuclear weapons in a era free of nuclear testing. As long as we have unique access to facilities like the NIF, which can approach the extreme physical conditions within exploding nukes, we will have a significant leg up on the competition as long as the test ban remains in place. For that, if for no other reason, we should keep our fingers crossed that the NIF team can finally clear the last technical hurdles and reach the goal they have been working towards for so long.
Posted on November 21st, 2011 No comments
Stephen Hawking is in the news again as an advocate for space colonization. He raised the issue in a recent interview with the Canadian Press, and will apparently include it as a theme of his new TV series, Brave New World with Stephen Hawking, which debuts on Discovery World HD on Saturday. There are a number of interesting aspects to the story this time around. One that most people won’t even notice is Hawking’s reference to human nature. Here’s what he had to say.
Our population and our use of the finite resources of planet Earth are growing exponentially, along with our technical ability to change the environment for good or ill. But our genetic code still carries the selfish and aggressive instincts that were of survival advantage in the past. It will be difficult enough to avoid disaster in the next hundred years, let alone the next thousand or million.
The fact that Hawking can matter-of-factly assert something like that about innate behavior in humans as if it were a matter of common knowledge speaks volumes about the amazing transformation in public consciousness that’s taken place in just the last 10 or 15 years. If he’d said something like that about “selfish and aggressive instincts” 50 years ago, the entire community of experts in the behavioral sciences would have dismissed him as an ignoramus at best, and a fascist and right wing nut case at worst. It’s astounding, really. I’ve watched this whole story unfold in my lifetime. It’s just as stunning as the paradigm shift from an earth-centric to a heliocentric solar system, only this time around, Copernicus and Galileo are unpersons, swept under the rug by an academic and professional community too ashamed of their own past collective imbecility to mention their names. Look in any textbook on Sociology, Anthropology, or Evolutionary Psychology, and you’ll see what the sounds of silence look like in black and white. Aside from a few obscure references, the whole thing is treated as if it never happened. Be grateful, dear reader. At last we can say the obvious without being shouted down by the “experts.” There is such a thing as human nature.
Now look at the comments after the story in the Winnipeg Free Press I linked above. Here are some of them.
“Our only chance of long-term survival is not to remain lurking on planet Earth, but to spread out into space.” If that is the case, perhaps we don’t deserve to survive. If we bring destruction to our planet, would it not be in the greater interest to destroy the virus, or simply let it expire, instead of spreading its virulence throughout the galaxy?
And who would decide who gets to go? Also, “Our only chance of long-term survival is not to remain lurking on planet Earth, but to spread out into space.” What a stupid thing to say: if we can’t survive ‘lurking’ on planet Earth then who’s to say humans wouldn’t ruin things off of planet Earth?
I will not go through any of this as I will be dead by then and gone to a better place as all those who remain and go through whatever happenings in the Future,will also do!
I’ve written a lot about morality on this blog. These comments speak to the reasons why getting it right about morality, why understanding its real nature, and why it exists, are important. All of them are morally loaded. As is the case with virtually all morally loaded comments, their authors couldn’t give you a coherent explanation of why they have those opinions. They just feel that way. I don’t doubt that they’re entirely sincere about what they say. The genetic programming that manifests itself as human moral behavior evolved many millennia ago in creatures who couldn’t conceive of themselves as members of a worldwide species, or imagine travel into space. What these comments demonstrate is something that’s really been obvious for a long time. In the environment that now exists, vastly different as it is from the one in which our moral predispositions evolved, they can manifest themselves in ways that are, by any reasonable definition of the word, pathological. In other words, they can manifest themselves in ways that no longer promote our survival, but rather the opposite.
As can be seen from the first comment, for example, thanks to our expanded consciousness of the world we live in, we can conceive of such an entity as “all mankind.” Our moral programming predisposes us to categorize our fellow creatures into ingroups and outgroups. In this case, “all mankind” has become an outgroup or, as the commenter puts it, a “virus.” The demise, not only of the individual commenter, but of all mankind, has become a positive Good. More or less the same thing can be said about the second comment. This commenter apparently believes that it would be better for humans to become extinct than to “mess things up.” For whom?
As for the third commenter, survival in this world is unimportant to him because he believes in eternal survival in a future imaginary world under the proprietership of an imaginary supernatural being. It is unlikely that this attitude is more conducive to our real genetic survival than those of the first two commenters. I submit that if these commenters had an accurate knowledge of the real nature of human morality in the first place, and were free of delusions about supernatural beings in the second, the tone of their comments would be rather different.
And what of my opinion on the matter? In my opinion, morality is the manifestation of genetically programmed traits that evolved because they happened to promote our survival. No doubt because I understand morality in this way, I have a subjective emotional tendency to perceive the Good as my own genetic survival, the survival of my species, and the survival of life as it has evolved on earth, not necessarily in that order. Objectively, my version of the Good is no more legitimate or objectively valid that those of the three commenters. In some sense, you might say it’s just a whim. I do, however, think that my subjective feelings on the matter are reasonable. I want to pursue as a “purpose” that which the evolution of morality happened to promote; survival. It seems to me that an evolved, conscious biological entity that doesn’t want to survive is dysfunctional – it is sick. I would find the realization that I am sick and dysfunctional distasteful. Therefore, I choose to survive. In fact, I am quite passionate about it. I believe that, if others finally grasp the truth about what morality really is, they are likely to share my point of view. If we agree, then we can help each other. That is why I write about it.
By all means, then, let us colonize space, and not just our solar system, but the stars. We can start now. We lack sources of energy capable of carrying humans to even the nearest stars, but we can send life, even if only single-celled life. Let us begin.
Posted on November 1st, 2011 No comments
The move away from nuclear power in Europe is becoming a stampede. According to Reuters, the Belgians are now on the bandwagon, with plans for shutting down the country’s last reactors in 2025. The news comes as no surprise, as the anti-nukers in Belgium have had the upper hand for some time. However, the agreement reached by the country’s political parties has been made ”conditional” on whether the energy deficit can be made up by renewable sources. Since Belgium currently gets about 55 percent of its power from nuclear, the chances of that appear slim. It’ s more likely that baseload power deficits will be made up with coal and gas plants that emit tons of carbon and, in the case of coal, represent a greater radioactive hazard than nuclear because of the uranium and thorium they spew into the atmosphere. No matter. Since Fukushima global warming hysteria is passé and anti-nuclear hysteria is back in fashion again for the professional saviors of the world.
It will be interesting to see how all this turns out in the long run. In the short term it will certainly be a boon to China and India. They will continue to expand their nuclear capacity and their lead in advanced nuclear technology, with a windfall of cheaper fuel thanks to Western anti-nuclear activism. By the time the Europeans come back to the real world and finally realize that renewables aren’t going to cover all their energy needs, they will likely be forced to fall back on increasingly expensive and heavily polluting fossil fuels. Germany is already building significant new coal-fired capacity.
Of course, we may be dealt a wild card if one of the longshot schemes for taming fusion on the cheap actually works. The odds look long at the moment, though. We’re hearing nothing but a stoney silence from the National Ignition Facility, which bodes ill for what seems to be the world’s last best hope to perfect inertial confinement fusion. Things don’t look much better at ITER, the flagship facility for magnetic fusion, the other mainstream approach. There are no plans to even fuel the facility before 2028.
Posted on November 3rd, 2010 No comments
DARPA seems to have its priorities straight when it comes to space exploration. The agency is funding what it calls the “100 Year Starship” program to study novel propulsion systems with the eventual goal of colonizing space. Pete Worden, Director of NASA’s Ames Center, suggests that Mars might be colonized by 2030 via one-way missions. It’s an obvious choice, really. There’s little point in sending humans to Mars unless they’re going to stay there, and, at least from my point of view, establishing a permanent presence on the red planet is a good idea. My point of view is based on the conclusion that, if there’s really anything that we “ought” to do, it’s survive. Everything about us that makes us what we are evolved because it promoted our survival, so it seems that survival is a reasonable goal. There’s no absolutely legitimate reason why we should survive, but, if we don’t, it would seem to indicate that we are a dysfunctional species, and I find that thought unpleasant. There, in a nutshell, is my rationale for making human survival my number one priority.
If we seek to survive then, when it comes to planets, it would be unwise to put all of our eggs in one basket. Steven Hawking apparently agrees with me on this, as can be seen here and here. In his words,
It will be difficult enough to avoid disaster on planet Earth in the next hundred years, let alone the next thousand, or million. The human race shouldn’t have all its eggs in one basket, or on one planet. Let’s hope we can avoid dropping the basket until we have spread the load.
Not unexpectedly in this hypermoralistic age, morality is being dragged into the debate. The usual “ethics experts” are ringing their hands about how and under what circumstances we have a “right” to colonize space, and what we must do to avoid being “immoral” in the process. Related discussions can be found here and here. Apparently it never occurs to people who raise such issues that human beings make moral judgments and are able to conceive of such things as “rights” only because of the existence of emotional wiring in our brains that evolved because it promoted our survival and that of our prehuman ancestors. Since it evolved at times and under circumstances that were apparently uninfluenced by what was happening on other planets, morality and “rights” are relevant to the issue only to the extent that they muddy the waters.
Assuming that others agree with me and Dr. Hawking that survival is a desirable goal, then ultimately we must seek to move beyond our own solar system. Unfortunately there are severe constraints on our ability to send human beings on such long voyages owing to the vast amounts of energy that would be necessary to make interstellar journey’s within human lifetimes. For the time being, at least, we must rely on very small vessels that may take a very long time to reach their goals. Nanotechnology is certainly part of the answer. Tiny probes might survey the earth-like planets we discover to determine their capacity to support life. Those found suitable should be seeded with life as soon as possible. Again, because of energy constraints, it may only be possible to send one-celled or very simple life forms at first. They can survive indefinitely long voyages in space, and would be the logical choice to begin seeding other planets. Self-replicating nano-robots might then be sent capable of building a suitable environment for more complex life forms, including incubators and surrogate parents. At that point, it would become possible to send more complex life forms, including human beings, in the form of frozen fertilized eggs. These are some of the things we might consider doing if we consider our survival important.
Of course, any number of the pathologically pious among us might find what I’ve written above grossly immoral. The fact remains that there is no legitimate basis for such a judgment. Morality exists because it promoted our survival. There can be nothing more immoral than failing to survive.
Posted on October 23rd, 2010 8 comments
Thorium is a promising candidate as a future source of energy. I just wonder what it is about the stuff that inspires so many people to write nonsense about it. It doesn’t take a Ph.D. in physics to spot the mistakes. Most of them should be obvious to anyone who’s taken the trouble to read a high school science book. Another piece of misinformation has just turned up at the website of Popular Mechanics, dubiously titled The Truth about Thorium and Nuclear Power.
The byline claims that, “Thorium has nearly 200 times the energy content of uranium,” a statement I will assume reflects the ignorance of the writer rather than any outright attempt to deceive. She cites physicist Carlo Rubbia as the source, but if he ever said anything of the sort, he was making some very “special” assumptions about the energy conversion process that she didn’t quite understand. I assume it must have had something to do with his insanely dangerous subcritical reactor scheme, in which case the necessary assumptions to get a factor of 200 would have necessarily been very “special” indeed. Thorium cannot sustain the nuclear chain reaction needed to produce energy on its own. It must first be transmuted to an isotope of uranium with the atomic weight of 233 (U233) by absorbing a neutron. Strictly speaking, then, the above statement is nonsense, because the “energy content” of thorium actually comes from a form of uranium, U233, which can sustain a chain reaction on its own. However, let’s be charitable and compare natural thorium and natural uranium as both come out of the ground when mined.
As I’ve already pointed out, thorium cannot be directly used in a nuclear reactor on its own. Natural uranium actually can. It consists mostly of an isotope of uranium with an atomic weight of 238 (U238), but also a bit over 0.7% of a lighter isotope with an atomic weight of 235 (U235). U238, like thorium, is unable to support a nuclear chain reaction on its own, but U235, like U233, can. Technically speaking, what that means is that, when the nucleus of an atom of U233 or U235 absorbs a neutron, enough energy is released to cause the nucleus to split, or fission. When U238 or natural thorium (Th232) absorbs a neutron, energy is also released, but not enough to cause fission. Instead, they become U239 and Th233, which eventually decay to produce U233 and plutonium 239 (Pu239) respectively.
Let’s try to compare apples and apples, and assume that enough neutrons are around to convert all the Th232 to U233, and all the U238 to Pu239. In that case we are left with a lump of pure U233 derived from the natural thorium and a mixture of about 99.3% Pu239 and 0.7% U235 from the natural uranium. In the first case, the fission of each atom of U233 will release, on average, 200.1 million electron volts (MeV) of energy that can potentially be converted to heat in a nuclear reactor. In the second, each atom of U235 will release, on average, 202.5 Mev, and each atom of Pu239 211.5 Mev of energy. In other words, the potential energy release from natural thorium is actually about equal to that of natural uranium.
Unfortunately, the “factor of 200″ isn’t the only glaring mistake in the paper. The author repeats the familiar yarn about how uranium was chosen over thorium for power production because it produced plutonium needed for nuclear weapons as a byproduct. In fact, uranium would have been the obvious choice even if weapons production had not been a factor. As pointed out earlier, natural uranium can sustain a chain reaction in a reactor on its own, and thorium can’t. Natural uranium can be enriched in U235 to make more efficient and smaller reactors. Thorium can’t be ”enriched” in that way at all. Thorium breeders produce U232, a highly radioactive and dangerous isotope, which can’t be conveniently separated from U233, complicating the thorium fuel cycle. Finally, the plutonium that comes out of nuclear reactors designed for power production, known as “reactor grade” plutonium, contains significant quantities of heavier isotopes of plutonium in addition to Pu239, making it unsuitable for weapons production.
Apparently the author gleaned some further disinformation for Seth Grae, CEO of Lightbridge, a Virginia-based company promoting thorium power. He supposedly told her that U233 produced in thorium breeders “fissions almost instantaneously.” In fact, the probability that it will fission is entirely comparable to that of U235 or Pu239, and it will not fission any more “instantaneously” than other isotopes. Why Grae felt compelled to feed her this fable is beyond me, as “instantaneous” fission isn’t necessary to prevent diversion of U233 as a weapons material. Unlike plutonium, it can be “denatured” by mixing it with U238, from which it cannot be chemically separated.
It’s a mystery to me why so much nonsense is persistently associated with discussions of thorium, a potential source of energy that has a lot going for it. It has several very significant advantages over the alternative uranium/plutonium breeder technology, such as not producing significant quantities of plutonium and other heavy actinides, less danger that materials produced in the fuel cycle will be diverted for weapons purposes if the technology is done right, and the ability to operate in a more easily controlled “thermal” neutron environment. I can only suggest that people who write popular science articles about nuclear energy take the time to educate themselves about the subject. Tried and true old textbooks like Introduction to Nuclear Engineering and Introduction to Nuclear Reactor Theory by John Lamarsh have been around for years, don’t require an advanced math background, and should be readable by any intelligent person with a high school education.
Posted on October 18th, 2010 No comments
According to Reuters (hattip Tim Blair), German scientists have discovered a new home heating technology that leverages the tendency of charged particles (in this case electrons) to transfer energy to a metal lattice when under the influence of an electromotive force. Although remarkably similar to old-fashioned incandescent bulbs, which were recently banned in the European Union, the devices can be easily distinguished therefrom by virtue of the fact that they are clearly marked “Heatball.”
According to the website set up to market the new devices, they are the,
Best invention since the lightbulb! …A heatball is an electrical resistance intended for heating. Heatball is action art! Heatball is resistance against regulations that are imposed without recourse to any democratic or parliamentary procedure, disenfranchising citizens.
Noting that a portion of the purchase price of each of the devices will be contributed to a fund to save the rainforests, the blurb continues,
Heatball is also a form of resistance against the senseless nature of measures to protect the environment. How is it possible to seriously believe that we can save the world’s climate by using energy efficient lightbulbs, while at the same time condoning the fact that the rainforests have been waiting in vain for their salvation for decades?
Making light of the absurd notion that the devices could be misused to produce light, the site adds,
In accordance with the instructions, the correct use of heatballs is to produce warmth. Would you use a toaster as a reading lamp? …The emission of light during the heating process is a result of the production technology. It is no reason for alarm, nor does it constitute legitimate grounds for a refund.
In the 20th century we found ways to beat Prohibition in the USA. May our German friends have similar success with their Heatballs in the 21st.
Posted on October 13th, 2010 No comments
Something over a year ago, the US government announced that four companies out of 17 that had applied for over a hundred billion dollars worth of federal loan guarantees for 21 proposed nuclear reactors had made what the Wall Street Journal called its “short list.” At the time, Carl from Chicago, who occasionally writes for ChicagoBoyz, penned an article expressing his “confusion” at the choices. Several seemingly logical candidates had been passed over, and, of the four picked, three were underfunded and had an assortment of legal and financial issues that made them dubious choices for coming up with the kind of capital needed to fund new construction. As it turns out, the feds should have listened to Carl. NRG, one of the two companies he picked as “least likely to succeed,” effectively dropped out of the game some time ago. Now, as he puts it, “the other shoe has dropped.” The other weak sister, Constellation Energy Group, just announced it is pulling out of negotiations to build the build the Calvert Cliffs 3 reactor in Maryland.
Separately, administration officials said they had approved a $1.06 billion loan guarantee for an Oregon wind farm, the world’s largest, after project developers waged a vigorous lobbying campaign to bring the year-long application process to a conclusion.
Rod notes the gross disparity in the terms and conditions of loans offered to the two industries:
Just in case anyone wonders why the wind farm project accepted its loan guarantee while Constellation refused, the key is in understanding the terms and conditions.
For a project that would have produced 4,000 jobs for 4-5 years in Maryland, the companies involved were being told that they had to PAY the US government a non refundable fee of $880 MILLION dollars in order to BORROW $7.5 billion for a project where they would have to invest at least 20% of the project cost as their own equity, thus giving them at least $2.0 billion in reasons to make sure the project succeeded.
In contrast, the wind farm, which will produce 400 jobs for a relatively short period during construction, was able to obtain a $1.06 billion dollar loan with NO CREDIT SUBSIDY COST at all. The ARRA has provided all of the money required for the credit subsidy cost for politically defined “renewable” energy via a change in section 1705 of the Energy Policy Act. In addition, section 1603 of the ARRA provides a CASH GRANT in lieu of a production tax credit of 30% of the cost of the project via a check within 6 months after the project closes. The wind project thus gets a $1.06 billion loan with no closing cost and the sponsors have no equity in the project at all since they get their 20% down payment back with a 50% kicker less than a year after the project starts.
In a word, hype about a “nuclear renaissance” can be taken with a grain of salt, at least until the government gets its act together. Meanwhile, the coal industry has reason to cheer. New coal gasification plants are being built in the US even as we speak. Among other things, they produce hydrogen, a long shot candidate as a non-polluting vehicle fuel to replace petroleum. Ideas for getting the stuff out of coal without releasing tons of CO2 in the process remain sketchy. Even more intriguingly, a firm is seriously looking into the possibility of building a coal liquefaction plant in Indiana. Whether they decide the new plant is financially feasible or not, the fact that such a project has made it this far along in the planning process demonstrates how close coal has come to becoming a viable replacement for petroleum. Given that the United States has over a quarter of the proved coal reserves in the entire world, and that those reserves are more than twice the size in terms of energy as the world’s remaining oil, that is a fact of no small significance.
Posted on June 14th, 2010 No comments
The Grey Lady seemed positively ecstatic about recent discoveries of mineral wealth in Afghanistan in an article that appeared yesterday. The finds include iron, copper, gold, and a host of other valuable materials valued at a cool $1 trillion. The most significant of them all may turn out to be lithium. Initial analysis indicates deposits at only one location as large as those of Bolivia, the country that now has the world’s largest known reserves.
Lithium has become increasingly important lately as a component of small but powerful batteries. It will become a lot more important if fusion energy ever becomes a reality. I don’t expect this to happen anytime soon. Even if the remaining scientific hurdles can be overcome, the engineering difficulties of maintaining the extreme conditions necessary for fusion reliably over the long periods necessary to extract useful electric power would be daunting. Fusion power would likely be too expensive to compete with alternative energy sources under the best of circumstances. However, that’s my opinion, and a good number of very intelligent scientists disagree with me. If they’re right, and the upcoming proof of principle experiments at the National Ignition Facility prove far more successful than I expect, or some scientific breakthrough enables us to tame fusion on much smaller and less costly machines, fusion power may yet become a reality.
In that case, lithium may play a far more substantial role in energy production than it ever could as a component of batteries. It could literally become the metallic “oil” of the future. The reason for that is the fact that the easiest fusion reaction to tame is that between two heavy isotopes of hydrogen; namely, deuterium and tritium. The “cross section” for the fusion reaction between these two isotopes, meaning the probability that it will occur under given conditions, becomes significant at substantially lower temperatures and pressures than competing candidates. The fly in the ointment is the availability of fuel material. Deuterium is abundant in nature. Tritium, however, is not. It must be produced artificially. The raw material is lithium.
It happens that the fusion reaction between deuterium and tritium results in the production of a helium nucleus and a very energetic neutron. This neutron can cause reactions in either of the two most common naturally occurring isotopes of lithium, Li-6 and Li-7, that produce tritium. Thus, the fusion reactions that may one day produce energy for electric power could also be leveraged to breed tritium if the reaction were made to take place in the vicinity of lithium, either in a surrounding blanket or one of several other more fanciful proposed arrangements.
As noted above, I don’t think that day is coming anytime soon. If it when it does, Afghanistan may well become the Saudi Arabia of a new technological era of energy production.