EDIT: There's another post on the front page right now that has a recording of the event: http://www.iflscience.com/physics/watch-germany-switch-their... discussion at https://news.ycombinator.com/item?id=11026559

The Wendelstein 7-X reactor is the largest fusion device created using the stellarator concept which was the brainchild of physicist Lyman Spitzer. It is planned to operate with up to 30 minutes of continuous plasma discharge, demonstrating an essential feature of a future power plant: continuous operation.

The name of the project, referring to the mountain Wendelstein in Bavaria, was decided at the end of the 1950s, referencing the preceding project from Princeton University under the name Project Matterhorn.

https://en.wikipedia.org/wiki/Wendelstein_7-X

If it doesn't work, well, they'll keep trying.

It's like when SpaceX landed that rocket over the ocean (without a barge) then let it crash- if they succeed, the cool stuff comes next.

The press loves to hype this sort of thing but I think if you talk to most scientists in the field they'll be much more circumspect about getting to commercial fusion. Personally I think it's at least twenty years out, and that's if everything goes well, which it will not.

https://en.wikipedia.org/wiki/Falcon_9_booster_landing_tests...

A better analogy might be for rockets / spaceflight-- where individual systems are rigorously tested independently, but a live launch is the only place that they all come together and have to function as one tightly coupled system.

I understand the point that you are trying to make, but your analogy is a bit poorly chosen.

Speaking from my days as a sounding rocket telemetry engineer, we performed lots of tests of the individual systems, as you say. But then we also put everything together and performed several "sequence tests" where the entire vehicle (minus the motor) was assembled and tested as if the countdown were real. All events were triggered as if the vehicle were in flight, and experiment systems were tested to ensure they would power on as expected and provide real data. If we had any deployables, the deployment mechanism would be tested to the maximum extent possible. These sequence tests happened off the rail (in special testing facilities) and on the rail (fully assembled in launch configuration, with a motor).

Basically, if you wait until the actual launch to perform integration tests of all of this, you WILL fail. There are too many pieces that need to function in concert to expect them to all work without integration testing.

(read the comments below their videos on their youtube channel to understand the difference)

The ITER vacuum vessel also looks pretty funny, though much more symmetrical: https://www.iter.org/mach/vacuumvessel

The ITER design is also dramatically complicated by the need to have robots fit in there to replace blanket modules.

It's designed to be maintained from the inside. So you need to get replacement/upgrade/experiment parts inside where you need them.

> and why is there so little homogeneity?

stellarators are highly asymmetrical

Perhaps later today?

The program should begin at any time.

EDIT: Err, CET... UTC+1. So, perhaps it is over?

    Das ist ungefährlicher und hinterlässt weniger stark verstrahlten Atommüll 

    This is dangerous and leaves less severely contaminated nuclear waste

    This is *less* dangerous and leaves less strongly contaminated nuclear waste

If something that would have killed you before, is less likely to do so now you would call it ungefährlicher or less dangerous but you wouldn't call it safer unless you're intending to be funny.

There are schemes to convert charged particle flux directly into electricity, but I'm not aware of any fusion power experiments that use them: https://en.wikipedia.org/wiki/Direct_energy_conversion

That's how we'll extract energy from fusion reactors, but with approximately 1 AU less distance.

I think only the shells of the superconducting coils are cooled to those temperatures. The rest of the system, including the containment walls, are water-cooled.

In a real system you would also have neutron radiation carrying away energy that could be captured with additional layers of water.

It has the double-win that if Lithium is added, the high energy neutrons end up breeding more Tritium fuel.

The one I heard of was the neutron blanket method

There's absolutely no question nor doubt that every fusion research reactor in history has been capable of sinking a tremendous amount of power :)

Edit: ah, I imagine you meant to direct me to the later "Power production" paragraph.