Holy Grail or Chimera ?
LIVERMORE, Calif. - (23 May 05) [All emph. add.] Ed Moses talks of the "grand challenge" that has consumed him for the past five years, comparing it to trying to hit the strike zone with a baseball from 350 miles away, or tossing a dime into a parking meter from 40 miles. [...]
In a building the size of a football stadium, engineers have assembled the framework for a network of 192 laser beams, each traveling 1,000 feet to converge simultaneously on a target the size of a pencil eraser.
The trip will take one-thousandth of a second during which the light's energy is amplified many billions of times to create a brief laser pulse [more powerful than] 1,000 times the electric generating power of the United States.
The goal is to create unimaginable heat - 180 million degrees Fahrenheit - and intense pressure from all directions on a BB-size hydrogen fuel pellet, compressing it to one-thirtieth of its size.
The result, the scientists hope, will be fusion ignition, so that more energy is released than is generated by the laser beams. [...]When completed in 2008, the National Ignition Facility, or NIF, as the laser at the Lawrence Livermore National Laboratories is called, will [...] provide a platform for many experiments in high-energy and high-density physics, from learning more about the planets and stars to advancing the elusive hunt for fusion energy to generate electric power, Moses says.
"You have to think of this like the Hubble," he says, referring to the space telescope. "It's a place where you will see things and do things that you couldn't do anywhere else."The government is investing $3.5 billion, and possibly several billion dollars more, in NIF for another reason: national security.
If NIF achieves fusion ignition, it will for the first time in a laboratory simulate the pressures and heat of a nuclear explosion, allowing nuclear weapons scientists to study the performance and readiness of the country's aging nuclear arsenal, without actually detonating a nuclear device. [...]
The NIF laser "is essential to assessing the potential performance of nuclear weapons," says Energy Secretary Samuel Bodman. He says the experiments will help determine the effects of aging on warheads and help assure they will work as expected, should they be needed.There have been other lasers, including a 10-beam Livermore project called Nova. NIF will produce 40 times to 60 times more energy. "It's the difference between a car and a jet engine," Moses says. [...]
The NIF program has had a decade of turbulent history marked by exhilarating successes and embarrassing setbacks, large cost overruns and charges by some critics that the project was oversold from the beginning to win initial support in Congress.
When the idea of a new, super laser first emerged in the early 1990s, the cost was put at less than $700 million. [...] Critics contend the price is now up to $5 billion when associated expenses such as developing a target capsule capable of achieving fusion ignition are included.
"If Congress knew it would cost $5 billion up front, would they ever have funded it? No way," maintains Christopher Paine, who [...] has been one of [NIF's] sharpest critics. [...]The program's critics charge that Livermore officials lowballed NIF's capabilities and potential cost from the beginning. When Congress was sold on NIF's importance because of its ability to simulate a nuclear explosion, scientists were at best only half certain fusion ignition could be accomplished, NIF program supporters acknowledge today.
Three years after NIF construction began, congressional auditors concluded in a 2000 report, "Congress cannot know with assurance just how much NIF will cost ... what impact NIF will have on the overall nuclear weapons program, or how long it will take to complete." [...]That report and others were prompted by discovery in late 1999 that engineers had encountered a serious problem installing the laser's optics [...] - they could not keep the optics free of dust. [...]
"The problem was, we had people doing this that did not appreciate the scale of what they were attempting to do," says Moses, a laser engineer and longtime senior manager at Livermore, who was brought in to lead the NIF program in late 1999. Those who had the vision of NIF found it was more complicated when it came to actually building it, he said. [...]By 2003, the dust issue was solved by building a massive clean room and installing the optics in modular dust-free units. Engineers found new ways to produce the thousands of highly polished pieces of laser glass. A faster way was found to grow high-quality crystals that convert the beams to ultraviolet just before they strike the target.
And with four of the planned 192 beams operating, new tests suggested strongly that when the system was fully operating, enough energy would be produced to (theoretically, at least) achieve ignition.
Last year, however, a new complication emerged - not over the laser but the pea-size pellet that contains the hydrogen fuel that will be ignited by the lasers to achieve fusion ignition. Could the pellet be manufactured to the required specifications?
Once its shell was to be made of plastic, but that idea was abandoned. Now the choice is beryllium, a metallic element that can withstand intense heat, is molecularly stable and is a good conductor.
It still is uncertain whether beryllium can be machined to specification, according to technicians who have monitored the program. Last year Congress directed another outside review to report how the development of a beryllium target might affect NIF's timetable.Like previous challenges in the project's history, the beryllium issue will be resolved, [Moses believes].
While the massive laser may one day have a broad range of scientific uses - some not even envisioned by today's scientists - the immediate focus remains assuring the reliability of the nation's nuclear arsenal without actually testing the weapons. [...]
By H. JOSEF HEBERT, Associated Press Writer
While I have absolute confidence that humans will someday generate most of our electricity with fusion, and that the U.S. are the leading candidate to achieve the breakthrough, it must be noted that we've been pursuing commercial civilian fusion for going on fifty years now, with only modest success to date.
However, as the article points out, many problems have been encountered in trying to build this "Hubble" of lasers, and all but one have been solved.
Further, it should be pointed out that the Hubble Space Telescope itself was far from problem free; at one point it wasn't certain that it could be successfully built, and after it was launched and had successfully achieved orbit, it was discovered that the optics STILL weren't right, necessitating an additional half-billion-dollar shuttle flight dedicated to fixing Hubble in orbit - which was in itself a pioneering feat of engineering.
The very bottom line is that spending a mere $ 5 billion over fifteen years, to acquire a national treasure like the NIF promises to be, is not only a very smart bet, it's also essentially gambling with pocket change.
Between 1993, and 2008 (when the NIF is scheduled to be completed), the total aggregated U.S. GNP will be on the order of $ 150 trillion, in nominal dollars.
$ 5 billion is 1/30,000th of $ 150 trillion, or the equivalent of the average American household spending $ 2, less than the cost of a Starbucks frappuccino.
If the NIF has even a one out of a hundred chance of leading to commercial fusion, then it's money overwhelmingly well spent.
In fact, even ten billion dollars would be a bargain.
3 Comments:
Well, $5B might seem like chump change to you, but there are two pieces of the equation you've left out. Could have that $5B been better spent (or not spent by government and thus by private industry) and if we'd just waited another decade or two, would've advances in technology made it far cheaper anyway.
I'm remain unconvinced that this was a good idea.
Yes, absolutely, advances in technology both make fusion possible, and make COMMERCIAL fusion a possibility.
The article lists three advances in technology and engineering practices, in addition to others that I'm sure weren't mentioned, that will make future lasing projects easier and cheaper, which is one of the benefits of a project of this groundbreaking nature.
You are correct that if the purpose of the project was to figure out how to make commercial fusion power generation a reality, it would have been wiser to wait another few decades, when it would have been easier.
However, the primary purpose of the NIF is to allow the U.S. to ensure that their stockpiled nukes remain "fresh", without having to explode any, so that America can put political pressure on countries that DO explode test nukes.
It's a politically driven non-proliferation project - the promise of abundant cheap energy is just the gravy, a potentially wonderful spillover benefit.
Otherwise, yes, spending $ 5 billion on biodiesel facilities and infrastructure would have been a safer bet, with proven benefits.
I agree that the $5 billion investment is worth the chance of acheiving a breakthrough in this field of research. If commercially viable fusion power is acheived in the future, it will be a huge boon for the world economy. We shouldn't look at these investments as either/or, we can invest in fusion and other technologies as well.
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