Building a star in a lab... Nuclear Fusion

[JeffKeryk]

Fusion Reactor

 

[LazyDog]

It is about time, we need to find better ways to get our energy.

 

[OVERKILL]

Being able to reliably produce power from a sustained fusion reaction is of course the holy grail. I'm quite intrigued to see if this goes anywhere beyond where previous efforts have taken us.

 

[gman2304]

I remember a couple of scientists in the late eighties or early nineties claimed that “cold fusion“ was just around the corner. Their theory was soon debunked. There is a saying that fusion is most likely 30 years away....and always will be!

 

[ABN_CBT_ENGR]

From the article...

"Produce more heat than it consumes"

OK, lets watch

 

[Kestas]

Heat needs to go into it to produce conditions for it to generate even more heat... kind of like introducing a lit match to get a campfire going.

These reactors are 10 times more damaging to the first wall than fission reactors. In graduate school I was part of a research group studying effects of radiation on metals. That was 30 years ago. And yes, back then we thought fusion was just 10 years away.

 

[BISCUT]

These temperature extremes are incomprehensible to a layman like me.



TEMPERATURE GRADIENT: ITER will include one of the hottest places in the universe—the vacuum vessel housing the 150-million-degree- Celsius plasma—as well as one of the coldest places in the universe; the magnets that will confine and control that plasma must be kept at about four kelvins (–269 degrees C). Separating the two will be a beryllium-coated steel “blanket” to shield the sections from each other, which will attach to the vacuum vessel’s interior wall via stub keys, currently covered by yellow caps to keep off dust.

 

[ABN_CBT_ENGR]

They are trying to make a Dyson Sphere.

Cant wait to see this one.......................................................................................

 

[jhellwig]

While they have made several advancements in fusion I think we are still closer to perpetual motion than net power output fusion.

Technically we do have a viable way to harness fusion.....

 

[Wolf359]

While they have made several advancements in fusion I think we are still closer to perpetual motion than net power output fusion.

Technically we do have a viable way to harness fusion.....

You have that backwards. Fusion is a know process. There's no scientific method for perpetual motion. At best, maybe you're thinking of the Casimir effect or Zero point energy, but no one has figure out any way to harness that yet. The theory for fusion is known, they've just been working out the engineering for the last several decades and it's still over a decade away.

 

[MolaKule]

From the article...

"Produce more heat than it consumes"

OK, lets watch

I noticed that as well. For a supposed science writer, the author obviously hasn't studied much nuclear physics, if any.

For a fusion reaction the containment of a plasma must be met with a critical volume of plasma ions (Nt/V) at approx. 10^27 ions per second per cubic meter, called the 'Lawson criterion."

The magnetic confinement of the plasma is critical in that if the volume is not constant, say if the fusion rate is too high, the confinement volume of the plasma expands, reducing the Nt/V, thereby reducing the reaction rate and the resulting thermal energy output reduces. So keeping the plasma volume (confinement volume) constant will be tricky.

WHAT WILL ITER DO?

The amount of fusion energy a tokamak is capable of producing is a direct result of the number of fusion reactions taking place in its core. Scientists know that the larger the vessel, the larger the volume of the plasma ... and therefore the greater the potential for fusion energy.

With ten times the plasma volume of the largest machine operating today, the ITER Tokamak will be a unique experimental tool, capable of longer plasmas and better confinement. The machine has been designed specifically to:

1) Produce 500 MW of fusion power
The world record for fusion power is held by the European tokamak JET. In 1997, JET produced 16 MW of fusion power from a total input heating power of 24 MW (Q=0.67). ITER is designed to produce a ten-fold return on energy (Q=10), or 500 MW of fusion power from 50 MW of input heating power. ITER will not capture the energy it produces as electricity, but—as first of all fusion experiments in history to produce net energy gain—it will prepare the way for the machine that can.

2) Demonstrate the integrated operation of technologies for a fusion power plant
ITER will bridge the gap between today's smaller-scale experimental fusion devices and the demonstration fusion power plants of the future. Scientists will be able to study plasmas under conditions similar to those expected in a future power plant and test technologies such as heating, control, diagnostics, cryogenics and remote maintenance.

3) Achieve a deuterium-tritium plasma in which the reaction is sustained through internal heating
Fusion research today is at the threshold of exploring a "burning plasma"—one in which the heat from the fusion reaction is confined within the plasma efficiently enough for the reaction to be sustained for a long duration. Scientists are confident that the plasmas in ITER will not only produce much more fusion energy, but will remain stable for longer periods of time.

4) Test tritium breeding
One of the missions for the later stages of ITER operation is to demonstrate the feasibility of producing tritium within the vacuum vessel. The world supply of tritium (used with deuterium to fuel the fusion reaction) is not sufficient to cover the needs of future power plants. ITER will provide a unique opportunity to test mockup in-vessel tritium breeding blankets in a real fusion environment.

5) Demonstrate the safety characteristics of a fusion device
ITER achieved an important landmark in fusion history when, in 2012, the ITER Organization was licensed as a nuclear operator in France based on the rigorous and impartial examination of its safety files. One of the primary goals of ITER operation is to demonstrate the control of the plasma and the fusion reactions with negligible consequences to the environment.

WHAT IS FUSION?​

Fusion is the energy source of the Sun and stars. In the tremendous heat and gravity at the core of these stellar bodies, hydrogen nuclei collide, fuse into heavier helium atoms and release tremendous amounts of energy in the process.
Twentieth-century fusion science identified the most efficient fusion reaction in the laboratory setting to be the reaction between two hydrogen isotopes, deuterium (D) and tritium (T). The DT fusion reaction produces the highest energy gain at the "lowest" temperatures.
Three conditions must be fulfilled to achieve fusion in a laboratory: very high temperature (on the order of 150,000,000° Celsius); sufficient plasma particle density (to increase the likelihood that collisions do occur); and sufficient confinement time (to hold the plasma, which has a propensity to expand, within a defined volume).

At extreme temperatures, electrons are separated from nuclei and a gas becomes a plasma—often referred to as the fourth state of matter. Fusion plasmas provide the environment in which light elements can fuse and yield energy.
In a tokamak device, powerful magnetic fields are used to confine and control the plasma.

https://www.iter.org/proj/inafewlines

 

[ripcord]

They are trying to make a Dyson Sphere.

Cant wait to see this one.......................................................................................

I'll believe it when I see it. As long as I can remember it's only been a billion years away...

 

[jhellwig]

You have that backwards. Fusion is a know process. There's no scientific method for perpetual motion. At best, maybe you're thinking of the Casimir effect or Zero point energy, but no one has figure out any way to harness that yet. The theory for fusion is known, they've just been working out the engineering for the last several decades and it's still over a decade away.

It was a joke.........

 

[mk378]

An interesting thing about the natural fusion reaction of stars is that energy production occurs at a very low rate per volume, which is offset by enormous volume. The fuel atoms mostly wait for billions of years for their chance to undergo fusion. A piece of the Sun burning in a reactor structure cubic meters in volume would produce only tens of kilowatts of heat.

So what would be necessary to have steady-state fusion sufficient to run a power plant is not only to replicate "a star on Earth", it would require scaling up the reaction rate by orders of magnitude. When a star does that, it blows apart.

 

[Wolf359]

An interesting thing about the natural fusion reaction of stars is that energy production occurs at a very low rate per volume, which is offset by enormous volume. The fuel atoms mostly wait for billions of years for their chance to undergo fusion. A piece of the Sun burning in a reactor structure cubic meters in volume would produce only tens of kilowatts of heat.

So what would be necessary to have steady-state fusion sufficient to run a power plant is not only to replicate "a star on Earth", it would require scaling up the reaction rate by orders of magnitude. When a star does that, it blows apart.

I believe you're referring to the action of the W boson which controls the rate of which stars fuse hydrogen into helium. If it weren't from the slow rate the W boson borrows energy from the Higgs field which was only discovered in 2012 although theorized for years before, we wouldn't exist as the sun would have burned up just a few million years after formation. The action basically converts protons to neutrons which lead to helium atoms instead of hydrogen. The W boson has been a part of the standard model which was developed in the 70s so it's well known.

The reason stars blow apart is that it runs out of hydrogen and gravity takes over. Has to be a certain mass though, our sun is too small to go supernova, will just swell to a red giant and then turn into a white dwarf and eventually a black dwarf. It takes so long to become a black dwarf that none yet exist in the universe. The sun is basically fusing regular hydrogen atoms, in a fusion reactor, they would use deuterium and tritium for fuel as it fuses at lower temperatures and yields more energy.

 

[Yah-Tah-Hey]

And to think the University of Utah thought they had more power coming out of a small device than went into producing it. A contraption sitting on a counter in a chemistry lab. All aboard the Garn Express for Salt Lake City.It's another miracle in the desert.

 

[Al]

I know more than a little....I have a lot of quantum physics knowledge and have been involved in pwr's my whole life. It ain't happening in your lives folks even if you are young.

 

[Wolf359]

I know more than a little....I have a lot of quantum physics knowledge and have been involved in pwr's my whole life. It ain't happening in your lives folks even if you are young.

It could be one of those things like AI which they talked about since the 70's but now it's actually making some progress. Marvin Minsky was big on it back in the day and never happened in his lifetime but kinda right afterwards. Seems like every time they build some fusion test rig they run into some issue but then they fix that and try another one and another thing pops up. Maybe eventually they'll figure it out. You could look at LIGO also, they spent decades and billions on that and nothing ever happened until just a few years ago. Now multi-messenger astronomy is the next big thing.

 

[ABN_CBT_ENGR]

Seems like every time they build some fusion test rig they run into some issue but then they fix that and try another one and another thing pops up. Maybe eventually they'll figure it out.

Its called "pathological science" for a reason. (definition of insanity). What they will have to "figure out" is a way around the 4 laws of thermodynamics and that's extremely unlikely to ever happen.

 

[Al]

It could be one of those things like AI which they talked about since the 70's but now it's actually making some progress. Marvin Minsky was big on it back in the day and never happened in his lifetime but kinda right afterwards. Seems like every time they build some fusion test rig they run into some issue but then they fix that and try another one and another thing pops up. Maybe eventually they'll figure it out. You could look at LIGO also, they spent decades and billions on that and nothing ever happened until just a few years ago. Now multi-messenger astronomy is the next big thing.

Yea..for sure. And obviously I am an outsider for this latest attempt. For now I am still from Missouri.