Controlling ITER with fuelers, ticklers, and terminators

September 9, 2015 by Leo Williams, Oak Ridge National Laboratory
The inside of a pellet selector, which directs pellets to different outputs in a fusion reactor.

When it's up and running, the ITER fusion reactor will be very big and very hot, with more than 800 cubic meters of hydrogen plasma reaching 170 million degrees centigrade. The systems that fuel and control it, on the other hand, will be small and very cold.

Pellets of frozen gas will be shot into the —some to keep it fueled, some to manage plasma activity, and some to extinguish the plasma as needed.

The idea of using frozen pellets to fuel a magnetic is not new. Researchers with ORNL's Fusion Materials and Nuclear Systems Division have been working on the technology for 35 years. Their handiwork helps run fusion experiments across the world, including America's largest fusion reactor, the DIII-D tokamak operated by General Atomics in San Diego.

Their expertise also made them the right choice to take on the much more challenging job of controlling ITER, which is more than eight times larger than the largest fusion reactor now in existence.

"The pellets are much more efficient at fueling the because they can penetrate fairly deep into the before being ablated and ionized into additional plasma," explained Larry Baylor of ORNL's Plasma Technology and Applications Group.

"The alternative method of injecting gas that is primarily used in today's smaller devices will not add fuel efficiently in ITER because of its large size and high magnetic field."

Baylor said his group is working on three types of pellet, which he refers to as fuelers, ticklers, and terminators.

Fuel pellets containing two hydrogen isotopes—deuterium and tritium—will be shot into the inside of the donut-shaped plasma to keep it burning. The pellets will be produced in a screw extruder chilled with liquid helium.

Helium in its liquid state is a chilly minus-452 degrees Fahrenheit, or four degrees above absolute zero. The cold turns the hydrogen into a liquid in the top of the extruder and a solid in the bottom.

At this point the hydrogen has a consistency not unlike toothpaste. The ORNL-designed device uses twin screws to pump the solid through a small nozzle, where it is cut into pellets and shot into the reactor with a device called a "repeating pneumatic gun."

Baylor said the are a little larger than .177-caliber air rifle pellets. To keep ITER going, the system will need to inject about four each second, or 15,000 an hour.

The same system produces the tickler pellets, which are about four times smaller than the fuel pellets. The tickler pellets are designed to prevent a fusion reactor's version of damaging solar flares—bits of plasma that peal off and hit the plasma-facing surfaces on the inner wall of the vessel. They do this by creating a series of smaller flares to diffuse the built-up energy.

"We want to make the flare-like events as small as possible," Baylor said. "We use the same device to shoot small hydrogen bullets to tickle the edge of the plasma so that it stays relatively stable."

Of all the pellets being designed by the ORNL team, the ticklers are the trickiest, Baylor said, because the experience gained from existing facilities such as the San Diego reactor is limited and high repetition rates are needed.

"The most difficult of the three to extrapolate is the tickler, because the ITER plasma is so much larger. It's a higher magnetic field, and hotter, and we cannot very well replicate the edge of the plasma conditions in DIII-D. That one is much more difficult."

The third type of pellet is meant to halt the fusion reactions altogether. It is for times when the whole plasma becomes unstable and threatens to come in contact and severely damage the plasma-facing surfaces of the containment vessel. These pellets are much larger than the others and are filled with frozen neon.

ITER will have around two dozen frozen terminator pellets ready to blast into the plasma. The system won't get much warning of an impending disruption—in some cases only about 20 milliseconds. As a result, the pellets will have to reach speeds over 670 miles an hour to get to the plasma in time.

The tubes that carry the terminator pellets into the plasma will have a sharp bend, causing the to shatter just before they reach the plasma and ensuring that the frozen neon is injected as a spray. The spray will stop the fusion reactions and cool the plasma, turning it back into a gas.

The instabilities are known as disruptions. Baylor said ITER's developers came to appreciate over time the serious possibility that 800 cubic meters of super hot plasma could damage the plasma-facing surface.

"When ITER was first designed, they really didn't worry too much about these disruption events," he explained. "Then, over time, they realized it could be a detriment to machine operation. So it's very critical that we develop a reliable mitigation technique to keep that from happening."

Baylor said the pellet systems will go through final design review during the 2018 federal fiscal year, which ends in September. He said they expect to deliver the systems to the ITER site in southern France starting in 2020.

Explore further: Using large cryogenic pellets, US ITER advances new fusion technology

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43 comments

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plaasjaapie
3.9 / 5 (9) Sep 09, 2015
ITER has and will continue produce far more physics PhDs than energy. It is not and has never been a serious attempt to harness fusion power in any useful way.
gkam
1.4 / 5 (25) Sep 09, 2015
This is just a game of physics.

We can get our power from more appropriate sources.
docile
Sep 09, 2015
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gkam
1.3 / 5 (23) Sep 09, 2015
And what will it cost to build and maintain these monsters?

We do not need them.

http://www.utilit...storage/
docile
Sep 09, 2015
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docile
Sep 09, 2015
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docile
Sep 10, 2015
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gkam
1.8 / 5 (25) Sep 10, 2015
Give us ten percent of what has been squandered on Fusion, and I'll give us clean alternative energy for all of us.

Or, how about if we had just part of the $4,000,000,000,000 we squandered on the Bush
Wars? We could change the grids and all have quiet and clean electric vehicles!
docile
Sep 10, 2015
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docile
Sep 10, 2015
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Nik_2213
4.2 / 5 (5) Sep 10, 2015
IIRC, ITER was never intended as a 'commercial' power generator. It is a 'proof of scaling', intended to wrangle the problems that just don't appear significant in a smaller device.

Must go much, much larger to generate 'grid' power.

Hey, but it is progress-- Like AI, fusion power seems to have been a dozen years away since the mid-century. Remember the 'Lazy-Eight' Stellerator ??
TheGhostofOtto1923
4.4 / 5 (20) Sep 11, 2015
Rossi pretty much disappeared after making waves with the E-cat...he claimed sales but wouldn't divulge to whom and that he had a production platform...not many public takers
You have no idea what you're talking about.

Rossi and IH just received their first US patent and Trademark after having completed third party testing and peer review. They're halfway through field testing of a 2mw reactor providing heat for a commercial production line.

And no, he never claimed sales as he hasn't yet produced a reactor for sale. This will happen some time after the current testing is complete.
TheGhostofOtto1923
4.3 / 5 (18) Sep 11, 2015
Educate yourself.
http://www.e-catworld.com/

-The thing may still not work but that's no excuse to be posting wrong info.

A US patent and Trademark, and a third party peer-reviewed test and paper.
warm fusion
He may be talking about rossis hot cat which apparently can operate above the melting point of nickel.
gkam
1.4 / 5 (21) Sep 11, 2015
Alternatives with which we can work are mostly what we need now. Why complicate things with fusion?

Read EF Schumacher and Small is Beautiful.
docile
Sep 11, 2015
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TheGhostofOtto1923
4.3 / 5 (18) Sep 11, 2015
Your newsletter is 4 years old.

"Andrea Rossi
August 15th, 2015 at 8:38 PM
Frank Acland:
Believe me: we are working very strong to prepare the manufacturing in massive quantities of the E-Cats, even if we still have brakes pulled due to the fact that we still do not know if the final results of the tests on course wil be positive or negative"

He may have taken orders for units not yet designed or constructed. I assume that when he has a working product he will fill them if they exist.
haven't heard much since the initial publications
-And like I say your info is years old.

He has a US patent and trademark.
He is halfway through validation of his commercial plant.
His process was independently tested and the subsequent paper was peer reviewed.

These are pretty significant facts you are apparently completely unaware of.

There are lots of LENR 'newsletters' and websites. Perhaps you should try one with more current info?

Or stay stupid.
docile
Sep 11, 2015
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docile
Sep 11, 2015
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Torbjorn_Larsson_OM
4.1 / 5 (9) Sep 12, 2015
Ugh, don't you just hate it when the trolls explode over a topic, and are whiners (losers) to boot?

So I know this is futile re trolls (and cold fusion trolls too, oy!) , but assuming other rational persons read this:

Meanwhile, NASA has presented results on that _all_ science is high ROI. The problem is that you can't tell which I will do the R, but that it is mutually reinforcing. If we don't do this - and we have excellent drive forces of clean, cheap energy - we lose money and other social benefits.

Also, the old complaint on 'decades away' was undercut over a decade ago, when at last the area knew enough to make a detailed time plan. If progress is delayed from the plan, it will be because politicians can act as stupid as trolls and divert good ROI money elsewhere.
docile
Sep 12, 2015
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TheGhostofOtto1923
4.5 / 5 (15) Sep 12, 2015
Heres a touching photo of rossi with his official US patent.
http://www.e-catw...t-photo/

God bless amerigo vespucci
Eikka
5 / 5 (16) Sep 13, 2015
Give us ten percent of what has been squandered on Fusion, and I'll give us clean alternative energy for all of us.


No you won't.

Your "clean alternative energy" costs in a year what ITER costs in two decades, and we still aren't any closer to any renewable solution.
gkam
1 / 5 (18) Sep 13, 2015
Yes, I will. What is this projection of nuclear technology liabilities to alternative technologies? Nukes get more and more expensive every day, while alternatives get cheaper, and do not need to guard dangerous wastes essentially forever.

No Police State required for alternative sources. Do you LIKE Police States?
Edenlegaia
5 / 5 (1) Sep 13, 2015
Yes, I will. What is this projection of nuclear technology liabilities to alternative technologies? Nukes get more and more expensive every day, while alternatives get cheaper, and do not need to guard dangerous wastes essentially forever.


It would be great if only you'd stop going full prophet to fight Nuclear, gkam. "dangerous wastes essentially forever"? Can you so easily predict we won't even be able to use them, that we won't alter them again to make them harmless?
There may be a limit to what alternative will offer to us. We may enter an age where tremendous amount of energy will be required for awesome (necessary? urgent?) missions, and you won't fuel that with two solar panel and a wind turbine.
We need alternative energy for some local production, yes. But nuclear is far from mastered and can still offer us more energy in a safier way. It's not like we would just say 'Oopsie we did a mistake, too bad, should we stop or go full nuclear?". We can correct that.
gkam
1 / 5 (18) Sep 13, 2015
"Can you so easily predict we won't even be able to use them, that we won't alter them again to make them harmless?"
-------------------------------------

No, I can't. But at age 71, I have seen and heard all the promises from "too cheap to meter" to "meltdowns are impossible". I have helped test some nuclear safety systems, and reached Senior Engineer level with PG&E long ago.

Will you just promise to stop making more nuclear waste until we can find a way to deal with it?
Irukanji
1 / 5 (1) Sep 14, 2015
I guess now all we need is a way to make large amounts of tritium and deuterium cheaply, and a means of actually getting electricity out of whole deal...it's a swirling magnetic field, no? Our primitive ape brain will just wrap wires around the mini-sun and call it a success
antialias_physorg
3 / 5 (2) Sep 14, 2015
Can you so easily predict we won't even be able to use them, that we won't alter them again to make them harmless?

You have to admit it's not a viable (business/ecological) decision to bank the success of a technology on an as yet unknown breakthrough in science

Unknown in two very important aspects:
- whether it's possible at all
and
- whether it's sensible/economically viable/ecologically tenable should it prove to be possible.

Saying that a technology is good without having answers to this seems more akin to religion than any kind of rational argument.

We may enter an age where tremendous amount of energy will be required for awesome (necessary? urgent?) missions

Like? Again you're arguing from unknowns. And why should they not be able to be fueled by wind/solar? These already provide more power in some countries than their respective nuclear reactors.
Eikka
5 / 5 (15) Sep 14, 2015
Yes, I will.


No. You won't.

You have no understanding of the scale of economics you're talking about. The money "squandered" on nuclear fusion research the world over for the past 50 years may come to a small fraction of money that is wasted every single year on massively subsiziding renewable energy production without any real advancements in the field that would actually enable us to build our whole societies on alternative power.

The ITER is estimated to cost $21 billion which is shared between 35 countries. The US federal government spends ~$39 billion EVERY YEAR on solar power subsidies, the more the more we built it, and we haven't even started on the integration problem because the contribution to the grid from solar power is still just under 0.5%

0.5% is roughly 2-3 GW which is similiar to the Vogtle nuclear plant extension - which only costs $15 billion - once - not every year for indefinitely.

Wake up and smell the coffee already.
Eikka
5 / 5 (15) Sep 14, 2015
And why should they not be able to be fueled by wind/solar?


Because there's no method to manufacture aluminium, steel, cement, glass, plastics, fertilizers, fibers... etc. directly on solar or wind power. Primarily because of cost and intermittency reasons.

For example, you can't practically run an aluminium production facility on power that becomes available intermittently because it's a molten electrolysis process that would become incredibly inefficient as a result. It keeps molten on the waste heat from the electrolysis, and when electrolysis isn't happening the pools must be heated by other means or they'll just freeze over and the whole process stops.

These already provide more power in some countries than their respective nuclear reactors.


Isn't that a slightly irrelevant comparison?

Similiar to how some countries are 100% renewable powered - because the only power station in the country happens to be a hydroelectric dam.
antialias_physorg
3.7 / 5 (3) Sep 14, 2015
The money "squandered" on nuclear fusion research the world over for the past 50 years may come to a small fraction of money that is wasted every single year on massively subsiziding renewable energy production

Please remember that the subsidies for nuclear in the same timeframe (during its infancy and first getting it to the grid) were 10 times as much as renewables are getting. Subsidies ran 70 (seventy!) cents per kWh at those times for nuclear. And - 60 years after getting into the market - nuclear still relies on subsidies on par of what renewables are getting per kWh produced. Even (foolishly) setting the whole waste issue aside nuclear makes no sense in any earthbound context.

I do think we should keep researching fusion - but as an off-world technology.
And slowly start to shift our subsidies for earthbound energy research onto storage technologies.

Eikka
5 / 5 (14) Sep 14, 2015
Please remember that the subsidies for nuclear in the same timeframe (during its infancy and first getting it to the grid) were 10 times as much as renewables are getting.


Please remember that these subsidies you're talking about were the US nuclear weapons program and please provide some citation.

The situation is hardly comparable, because we've been "helping the renewables" into the grid for the past 20-30 years and they still can't stand on their own, and there's no indication that they will ever be able to operate without this level of subsidy because the market mechanism simply doesn't work for them.

And - 60 years after getting into the market - nuclear still relies on subsidies on par of what renewables are getting per kWh produced.


That's is generally false. There are cases such as the UK where this is true, but in the US nuclear power only recieves about $2 per MWh from the feds, which is less than they pay in tax and other levies.
Eikka
5 / 5 (14) Sep 14, 2015
Anti-alias - also remember that an investment is not a subsidy. If a government buys a nuclear powerplant, that's an investment, and investments are expected to pay themselves back. If you spend a dollar and gain two, you haven't truly paid anything.

An investment becomes a subsidy when there is no expectation of a return of interest. In other words, it's an euphemism for a bad investment - you pay for something because you simply want to have it.

For example, we pay agricultural subsidies because we want to keep farmers around, even when there's overproduction of corn etc. and massive food waste - and because the farmers have a very powerful lobby and are using their influence to simply vote themselves money.

In a similiar way, we pay massive subsidies to renewable energy not because it's cheaper, not because it works, but because we want it and because renewable energy has a powerful lobby that uses their influence to simply vote themselves money.
gkam
1.2 / 5 (18) Sep 14, 2015
I get another quotation today from another solar PV company. I wanted to wait to buy power from Vogtle three, but it got SO delayed again, I gave up.

I would rather be at least semi-independent than rely on others.
antialias_physorg
5 / 5 (2) Sep 14, 2015
Here' sthe numbers for germany
http://www.polenu...ung-168/

Translation: since 1970s (when the state started investing in renewables:
Coal/oil/gas to date: 243bn
Nuclear to date: 187bn
All renewables combined (which already outproduce nuclear): 54bn
Add to that that the state covers up to 90 percent of any risks associated with nuclear energy (i.e. in case of a mishap it's almost all taxpayer money, which is another form of indirect subsidy) and that according to a recent study the reserve funds mandated by energy producers for decomissioning/waste disposal are woefully inadequate (i.e. the taxpayer will have to pay this too...another indirect subsidy that will ad tens of billions on top)
http://www.welt.d...ahr.html

Renewables are a steal compared to all other forms of energy.
antialias_physorg
3.7 / 5 (3) Sep 14, 2015
In combination this means the following. According to this study which looked at the numbers since since 1950s till 2010 and includes all the hidden subsidies:
https://www.green...tioniert
Nuclear gets 4.3 cent per kWh subsidy over all this time. Renewables get 2 cent.
If all costs were included up front then nuclear would cost 2,70 EUR per kWh (!)
There's just no way this is economically sensible (even ignoring all possible risks).

Even today - after 20 years of head start on renewables - nuclear isn't competitive. And given the falling prices for renewables never will be.
docile
Sep 14, 2015
This comment has been removed by a moderator.
gkam
1 / 5 (17) Sep 14, 2015
Is this what we want to continue?:

http://www.fierce...15-09-14

We cannot keep on killing ourselves for the benefit of the corporations which wanted to use Filthy Fuels, or expensive and dangerous technologies we cannot afford.

California had some of the highest energy prices in the nation, but now, have some of the best, about 25% below the average national price. Progress, alternative energy and the ability to see, mandate, and build the future did that, not short-term corporate profit-maximizing.
TheGhostofOtto1923
4.5 / 5 (15) Sep 14, 2015
So he claimed sales 4 years ago, for one of the reactors he built
Heres an even better one...

"Mon, 02 Dec 2013
"Andrea Rossi, founder, leader, and technology driver at Leonardo Corporation has opened the ECAT LENR device's web site where pre-orders can be made. For those concerned about the risks, there isn't a provision for funding, entering personal financial details or entering other revealing personal details. One simply gets a place on the list.

"Mr. Rossi is still being quite careful. Potential customers must comply with several criteria set by Leonardo Corporation in order to qualify for a purchase of an ECAT 1MW plant... pre-orders will be subjected to a routine due-diligence process.

"No money allowed, it looks as if both sides of a deal will get full assurances and an opportunity for due diligence. Before long one would expect one or more running units for inspections."

-What makes you think he wont honor these pre-orders once units are for sale?
TheGhostofOtto1923
4.3 / 5 (17) Sep 14, 2015
Sorry schott if you dont know how to search for proper references.
So he claimed sales 4 years ago, for one of the reactors he built...what...those "don't count"?
No, they dont. Testing and upgrading continue on the unit he 'sold' to that one customer, as part of his one-year testing and validation. Rossi tends to it onsite daily. Hes not about to sell or lease units that havent been thoroughly tested and UL-approved and patented.

He just got a US patent did you know it? No, you didnt.
Just admit you fucked up and go beat off to the Hitler poster above your bed
I kind of prefer eva if its all the same to you. Snot-boy.
Edenlegaia
5 / 5 (3) Sep 14, 2015
@gkam
Of course. Just let me ask for a complete stop of nuclear reactors and drop of energy production. It may take a while. Given your age, i know you may be in a hurry, but that kind of things takes time....unfortunately. Sarcasms aside, nuclear wastes and the system who create them are here. Sure, it's awful, but it's the result of what we began and now must endure and, maybe one day, transform. Hopefully, to something better and harmless.

@antialias
It may be. But it's unknown how much we'll be able to miniaturize those. I think there's more chance to find a way to make small and powerful nuclear reactors than solar/wind ones. What's more, storage technology won't be of any use when in need of continuous energy production for a long, long time. In place where solar and wind energy can't be provided. I still think those technologies will be useful for local production, but we must find something more powerful, and make it safer as well. Maybe the hardest part but not impossible
gkam
1.2 / 5 (18) Sep 14, 2015
"Of course. Just let me ask for a complete stop of nuclear reactors and drop of energy production. It may take a while."
-------------------------------------

Your exaggerations prove nothing. I understand the life cycle of powerplants.
TheGhostofOtto1923
4.5 / 5 (15) Sep 16, 2015
Your exaggerations prove nothing. I understand the life cycle of powerplants
-Like a janitor understands the life cycle of power plants?
docile
Sep 17, 2015
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