Of Coconut Futures and Thermonuclear Fusion Power
There may soon be a run on coconut futures. Vintage 2002 Indonesian coconut-shell charcoal is being used to help build what may become the first commercially viable Tokamak fusion power electrical generating facility near Cadarache in the south of France – about 38 miles from the Mediterranean.
Tokamak (from the Russian for “toroidal chamber with magnetic coils”) is a type of magnetic confinement device for producing controlled thermonuclear fusion power. The coconut charcoal is an environmental sponge that “adsorbs” the helium and hydrogen byproducts of the thermonuclear fusion reaction.
In what sounds like it could be the beginnings of a Star Trek-like Federation, the United States has joined the European Union, Japan, the Russian Federation, China, Korea, and India in negotiations for the establishment of the burning plasma prototype facility called ITER, which in Latin means "the way."
The fusion power produced by ITER will be at least 10 times greater than the external power delivered to heat the plasma. It’s not quite a Starship warp drive, but it does harness the power of the sun.
ITER is expected to cost more than $10 billion. Skeptics point out that ever since the idea of fusion power was first touted in the 1950s, fusion’s promise of clean power has receded endlessly into the future. Here’s a short video on the promise of ITER:
The Tokamak building is the core of ITER, where fusion experiments are planned to start in 2018. The reinforced concrete structure will sit with 5 1/2 stories underground and nineteen stories above. Adjacent to the main building, an assembly hall will be the location for pre-assembly of Tokamak components.
In ITER, the fusion reaction is achieved in Tokamak using magnetic fields to contain and control hot plasma. The fuel –- a mixture of deuterium and tritium, both isotopes of hydrogen –- is heated to temperatures in excess of 150 million°C, forming helium and neutrons in addition to the hot plasma. A helium nucleus carries an electric charge that responds to the magnetic fields of the Tokamak, and remains confined within the plasma. Approximately 80% of the energy produced is carried away from the plasma by neutrons — a neutron has no electrical charge and is unaffected by magnetic fields. The neutrons are absorbed by the surrounding walls of the Tokamak, transferring their energy to the walls as heat.
This is where the coconuts come into the picture. The coconuts will be used to generate a cooling vacuum essential to ITER’s operation. In the central chamber, some of this vacuum separates the plasma from the surrounding solid walls and allows fusion to proceed unhindered by air molecules. The vacuum pumps suck air out of ITER and “adsorb” waste helium from the fusion reaction, along with other debris created when hot plasma smashes into the reactor wall.
"This can only be done with very large cryogenic pumps," says Christian Day of the Karlsruhe Institute of Technology in Germany. The cryogenic pumps capture loose helium and hydrogen through a process that involves atoms of the gases sticking loosely to a solid surface — the greater the surface area, the better. "We wanted a material that behaves like a sponge, with lots of internal surfaces," Day adds. After 20 years searching for the ideal adsorber –- including sintered metals and porous minerals called zeolites –- Day’s team decided on charcoal. And not just any charcoal. "We found that coconut-shell charcoal is the best," Day says. "It is somehow strange that you need this very natural material to make a fusion device."
Only one immediately available source does not cause global warming and that is nuclear energy, says Lovelock.
Thermonuclear fusion and coconuts – strange bedfellows. But is fusion energy really "the way?" as the name ITER suggests? Why bother to build a fusion reactor when there is an almost inexhaustible supply of energy from the sun? Why not spend the $10 billion (or probably more) on wind or solar power instead?
A New Scientist editorial makes the case: "Compared with the more exotic schemes for large-scale manipulation of the environment now coming under serious consideration –- which do look 50 years away –- fusion power is a racing certainty. It’s safer too. A technology that messes with our planet’s climate is what got us into trouble in the first place." Ecologist James Lovelock –- concerned that humanity will shortly be facing a series of catastrophes from global warming –- might agree with this assessment. “By all means, let us use the small input from renewables sensibly, but only one immediately available source does not cause global warming and that is nuclear energy,” says Lovelock.
Lovelock – famous for the “Gaia hypothesis” – refers to conventional nuclear fission power generation (with all its attendant radioactive waste byproducts), but he is essentially making the case that humanity can’t afford to wait for “more exotic” technologies like solar and wind (and possibly fusion) to come online because he feels that a reduction in greenhouse gas emissions needs more immediate action.
This isn’t to say that both sun-based solar and man-made fusion can’t coexist to help meet the world’s energy needs. According to ITER, fusion power stations producing 1-2 GW should be feasible within ten years – much the same size as standard fossil fuel power stations. Proposed space-based solar power from Solaren Corporation (see the h+ article Space-based Solar is Coming!) offers the possibility of scaling up to the same 1-2 GW range by 2020. Nanosolar, another solar start-up company, is building a solar cell production facility projected to generate 430 MW annually.
It’s good to know that there are options — and it’s ironic that the world’s 21st Century energy future could end up being a race between harnessing power from real and artificial suns. With fossil fuels “messing” with our climate, as both Lovelock and New Scientist suggest, it seems we’d best keep all our cards (and coconuts) on the table.
The aneutronic nuclear fusion reactor is a device much more well-conceived to harness the fusion energy than any other until now.
I have the feeling that only mega-installations of this type of reactor will be viable commercially. That means they wil not be used for small-scale production of energy.
Probably we will see gigant installations at strategic points in each part of the world that distribute electricity over long distances and that make hydrogen to use elsewhere.
My understanding “only” 15-20 years ago was the major problem with fusion reactors was containment. Everything they could come up with to try to contain the plasma was still so leaky as to render the fusion reaction too short lived to remotely be usable. People were working on the Tokamak design back then. I thought they would have abandoned it by now.
No mention is made of the technical difficulties that have had and would have to still be overcome. I’d like to know what the actual technical progress has been.
Much progress has been made but, from there’s still a long way to go with the tokamak approach to fusion energy production. The key difficulty may be the problem with “turbulence” in the contained plasma. At the energy levels visualised for ITER (the test facility being planned for construction in the South of France) the result of turbulence in the plasma could be that the machine suffers serious damage, with the possibility that the “cascade effect” of particles being ripped off the tokamak’s internal wall could compound the damage and wreck the machine very fast. Scientists are no doubt working on these issues, but they don’t seem set to get a result anytime soon.
Meanwhile another team of scientists has been moving ahead very fast on fusion energy development. These are the laser people. The National Ignition Facility in California is about to be able to demonstrate that fusion can be triggered with a very powerful laser (a world first)… and beyond that, the European HiPER Project is preparing to take the knowledge forward and develop a demonstrator reactor which will move from the NIF “single shot” result to a system which can operate continuously and produce electrical energy at grid levels.
The NIF achievement of Inertial Fusion Energy” will change the game… at that point, suddenly fusion really does become the new energy source. It burns no fossil fuels, makes no CO2, creates only a very small amount of low level radioactive waste and runs on a fuel which is abundant worldwide… for the very long term. The key fuel component is deuterium, which is to be found in sea water. Thus, once fusion energy is mastered, we have enough fuel for millions of years to come.
… But we need the tokamak system too ! Laser plants alone will not be enough, and multiple technology apporoaches bring safety in numbers and diversity.
If the lights are not to be allowed to start going out as the fossil fuels run low and nations are to be dissuaded from the otherwise inevitable “energy wars” of the future, we MUST have fusion energy… and soon !
They may be attracted by renewable technologies Governments must be encouraged to realise that there is no other valid method of meeting the enormous energy demands to which mankind has become accustomed. Mastering fusion energy will take a long time and cost a lot of money, but there are few things in this world more worthy of serious international cooperation and investment !
Hi all, forget about bigscale energy propaganda.
for real solutions. Energy is not a scarcity!!!
First off I like to say congratulations to our scientists of the world and others responsible for moving humanity forward and into cleaner and more earth friendly energy sources.
Second, I like to condemn those who want to keep humanity locked into ignorant and/or ideological pits of despair, feast upon human misery and suffering either for power and control or for the hope that they gain entrance into the next world because they have given up on this one.
Third I like to congratulate those who attempt to stop these control freak ignorant’s from infecting and harming others, making the world a better place for all of humanity, who put their very lives on the line to keep us all, regardless of our political leanings, safe from harm.
Fourth I like to condemn those who resort to the lowest form of human behavior and rhetoric in order to advance their political agenda. They do this because they don’t have any convincing logical argument that their way of thinking is better than the other sides.