|
 I don't have any immediate plans to visit the U.K., and
that's largely due to weather. Some of the rainy reputation bestowed on the
center of the Commonwealth is undue, but at the same time, they're building fake
suns in Durham. Do you think Australia needs to build a fake sun?
Durham didn't quite do a homemade proton-proton chain or CNO
cycle. They took the easy way and filled a spherical balloon with helium. Then
a series of projectors animated the surface of the balloon with real-time video
of our actual sun. Another disappointment: this was an art installation for a
light festival known as Lumiere. While art is great and all, they're not going
to be setting up PV arrays or growing plants in northeast England. Heck, by the
time you read this the Durham Sun will no longer be on display.
Or course, that's not to say we as human kind haven't tried
to engineer an artificial sun. While we've pretty much got the hang of nuclear
fission reactors, it's been estimated that energy-sustainable nuclear fusion
reactors are still up
to 100 years away. This delay exists despite attempts to harness fusion energy
for commercial power purposes
had developed concurrently with fusion weapon testing. It's been speculated
that just one or two fusion reactors could power the entire world for hundreds
of years. Also, there would be zero chance of large-scale radioactive
catastrophes. Seriously, where is this stuff?
It
may be that our best hopes for harnessed fusion energy are on the foreseeable
horizon. Years of research have been spent charging plasma to create a magnetic
field which collapses the plasma inward. Once dense enough, the temperature
should be high enough for fusion to occur. The plasma itself is charged via an
electromagnet, as any type of electrode would liquefy. Significant progress was
made using this 'pinch' method in the 1950s and '60s, but this technique was determined
to have unpredictable neutron results.
 The pinch method was improved upon when used in a tokamak, an
energy confinement device which forces the plasma into the shape of a torus. The pinch method formed the plasma into a
poloidal magnetic field where plasma particles could cool. The tokamak
continues to be the preferred research option for fusion power. Since 2007, the
European Union, India, Japan, China, Russia, South Korea, and the United States
have been funding the construction of the International Thermonuclear
Experimental Reactor (ITER). This € 15 billion project will construct the
largest tokamak ever and will commence operation in 2020, but will essentially
be a laboratory for trial-and-error. While many researchers and scientists are
optimistic about the project, even those within ITER acknowledge there are no
firm expectations for when tokamak goes online. If ITER meets is objectives the
next project is DEMO, which will be a commercially-viable fusion power plant.
Opponents argue that material science hasn't caught up with
fusion confinement approaches. Research is ongoing into materials which could
withstand intense neutron bombardment.
Nobel laureate Pierre-Gilles de Gennes has stated, "We say that we will
put the sun into a box. The problem is, we don't know how to make the box."
Others have argued that the money dumped into ITER is better off going to other
fusion techniques, or spent combatting global warming.
 For those against ITER, there is hope in the form of
inertial laser containment. Progress has been so substantial in this field in
recent years that there could be a day where construction on ITER is
immediately halted. Laser inertial containment had been studied since 1962, but
at that time and in subsequent decades laser innovation was lackluster. A
high-energy laser system would be required to heat hydrogen atoms to the
temperatures found in stars. Early lasers were especially inefficient at the
infrared frequencies needed to cause a uniform implosion of the fuel. More
recent lasers have been employed at the U.S.'s National Ignition Facility. At a
test in August 2013, for the first time ever, more energy had been produced by
a fusion reaction than what had been invested in the fuel. Verification of this
is ongoing--the last thing we want is another cold fusion or bubble fusion
announcement--but it could be the sling that brings down the ITER Goliath.
Despite these recent advances, estimates for commercial fusion power are
still guessing its another 40 years.
And if fusion power is developed, what follows is a whole new series of
engineering challenges. Of course, that's not my problem. My problem will be
finding an affordable hotel in Durham when a real artificial sun is suspended
in the sky.
Resources
The Altantic Cities - A Gloomy English City Builds...
Wikipedia - Fusion power; Tokamak
ITER (Official Site)
Popular Mechanics - Is Fusion Power Finally For Real?
| 
Re: Where is My Fusion Reactor?
