Friday, January 4, 2013

Fusion Energy?s Dreamers, Hucksters, and Loons

ITER vacuum vessel The Cryostat forms the vacuum-tight container surrounding the ITER vacuum vessel and the superconducting magnets, essentially acting as a very large refrigerator. It will be made of stainless steel with thicknesses ranging from 50 mm to 250 mm. The structure is designed for 8,500 m3. Its overall dimensions will be 29.4 meters in diameter and 29 meters in height. The heavy weight will bring more than 3,800 tons onto the scale, making it the largest vacuum vessel ever built out of stainless steel.

Illustration ? 2012 ITER Organization.

Just a few weeks ago, a bunch of fusion scientists used South Korean money to begin designing a machine that nobody really thinks will be built and that probably wouldn't work if it were. This makes the machine only slightly more ludicrous than the one in France that may or may not eventually get built and, if and when it's finally finished, certainly won't do what it was initially meant to do. If you've guessed that the story of fusion energy can get a bit bizarre, you'd be right.

For one thing, the history of fusion energy is filled with crazies, hucksters, and starry-eyed naifs chasing after dreams of solving the world's energy problems. One of the most famous of all, Martin Fleischmann, died earlier this year. Along with a colleague, Stanley Pons, Fleischmann thought that he had converted hydrogen into helium in a beaker in his laboratory, never mind that if he had been correct he would have released so much energy that he and his labmates would have been fricasseed by the radiation coming out of the device. Fleischmann wasn't the first?Ronald Richter, a German expat who managed to entangle himself in the palace intrigues of Juan Peron, beat Fleischmann by nearly four decades?and the latest schemer, Andrea Rossi, won't be the last.

The reason's easy to see: On paper, fusion energy has almost unlimited potential. A fusion reaction releases an extraordinary amount of energy by slamming together light atoms, such as hydrogen, to make heavier ones, such as helium. (Fission is essentially the opposite: breaking apart heavy atoms, such as uranium, to make lighter ones.) Fusion is the same process that powers the sun?and it's so efficient that we'd have enough atomic fuel on Earth to satisfy our civilization's need for energy for, essentially, forever. The problem is that it's really hard to slam those atoms together hard enough. You need incredibly high temperatures, tens or hundreds of millions of degrees Celsius, so that the atoms are moving fast enough to get the reaction going. But as you heat your fuel up, you have to keep it contained. A 100-million-degree plasma wants to explode in all directions, but if you're going to keep the reaction going, you have to keep it bottled up. What do you make the bottle out of?

The sun's bottle is gravity. Because the sun is so massive?more than 300,000 times the mass of our planet?it has an enormous gravitational field. It's this field that compresses and constrains the hydrogen fuel and keeps it from flying off every which way. But without a sun-size mass to provide the gravity, you've got to find other ways.

One way?and it works beautifully?is to use an atom bomb as the bottle. On Nov. 1, 1952, America used fusion energy to wipe the Pacific island of Elugelab off the face of the planet. The device at the heart of the "Ivy Mike" test was essentially a big, chilly tank of heavy hydrogen. At one end was a Nagasaki-type plutonium bomb, which, when it exploded, compressed the fuel, heated it to millions of degrees, and kept it bottled up. For a fraction of a second, we unleashed the power of the sun upon the surface of the Earth. The bomb that leveled Hiroshima was the equivalent of about 15 kilotons of TNT. Ivy Mike was about 10 megatons, nearly 700 times as powerful. And there is theoretically no upper limit to how large you can make these devices if you so desire. (The Soviet Union detonated a 50-megaton whopper in the 1960s.)

The design works, but it?s a pretty poor solution to the world's energy needs. It's tough to turn a fusion weapon into a safe supplier of electricity. That isn't to say we haven't tried to harness the H-bomb. Edward Teller, the Strangelove-ian father of Ivy Mike, tried to convince the world that fusion weapons could be used for peaceful purposes, from controlling the weather to nuclear fracking to carving an Alaskan harbor out of bedrock to nuking the moon. Yes, Edward Teller wanted to nuke the moon to, in his words, "observe what kind of disturbance it might cause."

Teller's dream of unlimited fusion energy didn't die with him. The Lawrence Livermore National Laboratory, Teller's former stomping grounds, is now the site of a monstrous $4 billion-plus fusion project known as the National Ignition Facility. The idea is to compress and bottle up a pea-sized pellet of hydrogen by using a laser so huge that it would make any red-blooded moon-nuking megalomaniac proud. The putative goal is to generate more energy through fusing hydrogen atoms than the energy that was put in by the laser in the first place. And NIF scientists say that they'll achieve success in 2010 ... rather, they'll achieve success by October 2012 ... rather, NIF has succeeded at the crucial goal of showing that Livermore scientists' predictions of success were all dead wrong.

It's par for the course. Livermore has been predicting imminent success with laser fusion since the late 1970s?always failing miserably at fulfilling every prediction. In fact, critics (myself included) have long said that all the chin music about NIF being a source of fusion energy was nonsense. The laser is designed for studying nuclear weapons, not for generating energy. (And it won't even do the weapons job very well.) Yet scientists at Livermore keep pretending that their hyper-expensive laser research is somehow going to produce fusion energy, even though they've got to go through Rube Goldberg-esque variations of the idea to make it look like they've got a shot at success. (For those keeping score at home, the latest project, too, will be an abject failure if it ever gets funding.)

Livermore is far from alone when it comes to overselling fusion. Way back in 1955, before the invention of the laser, physicists were predicting that fusion energy would be on tap within 20 years. Back then, the only workable method of bottling up a cloud of million-degree hydrogen, short of setting off an atomic bomb, was to use giant magnets. At that time, a number of scientists around the world attempted to design machines that would heat and confine burning hydrogen clouds with powerful electromagnetic fields. They didn't work as predicted; even after decade upon decade of false starts, the magnetic bottles were just too leaky. Yet fusion energy was still always just around the next corner.

Magnetic fusion wasn't just for the Americans, but also for the Soviets, the Germans, the Japanese, the British?everybody who was anybody had a magnetic fusion program that would put power on the grid within the next few decades. At least this was the case until the 1985 Soviet-American Summit in Geneva, when Reagan and Gorbachev agreed that our countries would research fusion energy together. Within a few years, everybody who was anybody was now part of a big multibillion-dollar project to build a giant magnetic fusion bottle known as ITER.


daytona 500 national pancake day ohio school shooting sean young arrested matt kenseth bridge to nowhere primary results

No comments:

Post a Comment

Note: Only a member of this blog may post a comment.