2021 state of the horse race: ITER vs. dark horses

[Giorgio]

Anyone understand how they get to that number?

Rough Numbers:
Fusion output: 1200 MWth.
From the PDF I sent you some days before at page 4 :
ETAe= 0.9 ETAcdc= 0.7 ETAddc= 0.85 ETAth= 0.45
So the electrical efficiency for the conversion is estimated at 45% or 540 MWe, and te expected Q is 5-8, so the injected power is between 150 to 240 MWe, and the average is around 190 Mwe. Remove this from 540 and you get the 350 MWe of the pdf you linked.

[Giorgio]

How can 1,200 MWth be "low value heat"?

The thermal load will be roughly 50% of that, so around 600MWth distributed more or less over all the machine. Also according the PDF they are expecting a peak heat flux of 1 to 2 MWth/m2 (or 100 to 200 W/cm2). Making a high pressure steam recovery system over all the 80 meters of the machine seems quite a challenging engineering issue. My guess is that they made no mention of a thermal recovery cycle because with such a low heat flux (and wide surface) it makes more economic sense to quickly remove the heat with a cooling fluid and limit the temperature stress over the machine.
Even if you recover all of the heat as a working fluid you can probably get out roughly 40% as electric power (after removing all ancillaries and equipment), so an extra 240 MWe. It does not look really economical if you consider the added capital costs and complexity.

[mvanwink5]

The problem with peakers is thermal cycling. The problem with solar is low power density, the need for storage, no support for heavy industry which is a 24hr operation. Wind has fatal weather issues, Germany, England, Texas can attest to that.

There were cost numbers for GF a long time ago and given that their machine design, that has not changed. It is a drop in retrofit to existing thermal steam plant boiler island.

I suspect that all fusion plants will look similar once the auxiliary systems are added in. Everything has trade offs. ITER looks dead commercially.

The break point is when utilities finally realize fusion is the future. Solar cannot work for China and India, think about a city with 50 million people, hydroponic farms operating in winter.

It will be tough to say whose machine will dominate, at least for me, but to tell the truth, I don't really care.

[Skipjack]

How can 1,200 MWth be "low value heat"?

The thermal load will be roughly 50% of that, so around 600MWth distributed more or less over all the machine. Also according the PDF they are expecting a peak heat flux of 1 to 2 MWth/m2 (or 100 to 200 W/cm2). Making a high pressure steam recovery system over all the 80 meters of the machine seems quite a challenging engineering issue. My guess is that they made no mention of a thermal recovery cycle because with such a low heat flux (and wide surface) it makes more economic sense to quickly remove the heat with a cooling fluid and limit the temperature stress over the machine.
Even if you recover all of the heat as a working fluid you can probably get out roughly 40% as electric power (after removing all ancillaries and equipment), so an extra 240 MWe. It does not look really economical if you consider the added capital costs and complexity.

You are probably right about that. It might not be worth the effort in the end.

[Skipjack]

I suspect that all fusion plants will look similar once the auxiliary systems are added in. Everything has trade offs. ITER looks dead commercially.

I think that depends on the reactor design and fuel etc. Some (ZAP, Helion, LPPF, am I missing somone?) could be quite a bit smaller than others and some of them will even have direct conversion. So they might be in a building as small as a large single family home or small warehouse.
The smaller the reactor, the lower the overnight cost, which reduces risks for investors and makes it viable for more than just large utilities.
TAE is certainly on the bigger side. 80 meters in length for the reactor vessel alone is approaching ITER- like dimensions, though simpler geometry and overall simpler design still result in a smaller footprint for the whole facility. It is still seems big to me.
Helion's reactor is supposed to be about 20 meters in length and just 2 meters tall. So quite a bit smaller. It also produces less power, though.
ZAP's reactor core is tiny at just some 2 meters or so in diameter and height (including the Lithium- Lead tank around it). They will need a steam power plant though, will that comes with that. The smallest and most compact I have seen so far would be LPPF. Question is whether they can get it to work (though to be fair that question applies to everyone).
I agree that ITER sized Tokamaks won't lead to anything that is commercially viable. The entire facility would be big and expensive. Tritium inventory for startup will be a serious problem (compare the numbers in the CFS presentation that I just posted!). So the overnight costs will be huge and that will mean a huge risk. The ITER-style Tokamaks better hope that Helion's design works. So that there will be more Tritium on the market for them to buy

[mvanwink5]

Is it just my imagination or are these main contenders ramping up their PR? Getting close enough to commercial to start beating their chests?

[Skipjack]

Is it just my imagination or are these main contenders ramping up their PR? Getting close enough to commercial to start beating their chests?

Some of them certainly are. General Fusion has been showing some more progress recently. TAE has been in the news a lot. Even Helion is making the occasional (yet relatively cryptic) post on Twitter and Linkedin now. They even updated their website a little bit (though no real new information on there, unfortunately).

Others have gone relatively quiet, though. Compact Fusion Systems just recently went on a complete blackout. Even their website says " currently in Stealth Mode". And they are not listed on the Fusion Industry Association website anymore. I know they were conducting some experiments with funding from ARPA-E, but I would be quite surprised if they were at or near break even when they went dark. It seems a bit too early in their development. But who knows?

[Skipjack]

Looks like Helion won the race and I called it! Sorry for crossposting, but I just can't help myself

Over 100 million degrees (>9 keV) temperatures in Trenta, their latest prototype.
95% energy recovery for both energy input and energy output. Essentially they just have to get small amount of fusion gain to have an engineering Q>1.
They have a pretty new website:
https://www.helionenergy.com/

Press release:
https://www.helionenergy.com/wordpress/ ... verted.pdf
This is it folks!

[Carl White]

[mvanwink5]

Sorry, but the race is to contract. Did I miss the announcement for the Helion demonstration plant site? Is there any utility talking to Helion about a plant? We are long past science experimentation.

General Fusion was pound foolish, who from the US utilities will be traveling to the UK to look at a demo plant? Maybe Helion will be smarter when they finally announce their site location. They do plan to announce a demonstration plant this year?

[Skipjack]

Sorry, but the race is to contract. Did I miss the announcement for the Helion demonstration plant site? Is there any utility talking to Helion about a plant? We are long past science experimentation.

General Fusion was pound foolish, who from the US utilities will be traveling to the UK to look at a demo plant? Maybe Helion will be smarter when they finally announce their site location. They do plan to announce a demonstration plant this year?

I understood this thread was (by OP) about who would be first to have a Q (by any measure) that is above 1 and beat ITER to the punch.
Demo plants are one or more steps beyond that and mind you ITER is also NOT a Demo plant. That would literally be DEMO, LOL.
So either we stick with the OP's premise of the thread or we move the goal posts, in which case I would recommend starting a new thread. That is something I am perfectly comfortable with, but it has to be clear in the OP of the thread what exactly the goal for that race is.
In that case, we will also have to define the word "Demonstration Plant".
Personally, I define "demonstration plant" as a first of a kind (FOAK) plant that puts power on the grid. E.g. like the SMR- demo- plants that are currently being proposed by Nuscale, Terrapower and GE.
Applying those metrics, GF's so called demonstration plant in Culham, is no such thing. It does not even use tritium yet and will not demonstrate tritium breeding ratios, which are important for a D+T reactor. It will not produce a power output comparable to a tritium fueled plant, if it even manages to achieve a Q>1 (which will be hard for them with just D+D operation).
Equally, from the information provided by David Kirtley in the January NRC presentation, Helion's next prototype will likely (unless their plans have changed since then) not be a demonstration plant yet either, since it will not be able to operate 24/7 yet (at 1Hz, vs 1/600Hz for Trenta) and it will still be only an experimental reactor and not deliver power to the grid.
So what do you want to do? Make a new thread with a new goal post for "winner of the race"?

[Giorgio]

Looks like Helion won the race and I called it! Sorry for crossposting, but I just can't help myself

Over 100 million degrees (>9 keV) temperatures in Trenta, their latest prototype.
95% energy recovery for both energy input and energy output. Essentially they just have to get small amount of fusion gain to have an engineering Q>1.

The numbers are indeed interesting, but i think is still early to call them the winner of the Q>1 race.
I will look forward to their 2021 IEEE paper.

[mvanwink5]

This is not a horse race with betting slips. and commercial Fusion is not about a science experiment. This is about practical utility scale machines. Moreover, a demonstration machine only has to show the design in real life. If Helion has all the full or near enough full scale hardware, even if it operates for 1 minute at a time and 1/100 of the expected cycle rate, it does not matter. Demonstration only means that the design proves that the utility plant and the economics.

The balance of the plant too is important, and that can be at scale sufficient to prove the design and make economic and efficiency calculations. Remember, the regulatory agencies have to approve the plant and investors convinced of the return on their money. The divertor life for instance is important for Helion, hence it is what they talked about first if you will notice.

Neverltheless, it is good news. So, any word on a demonstration plant announcement? If not, why not? TAE has a roadmap to theirs, GF has announced theirs.

[Giorgio]

If Helion has all the full or near enough full scale hardware, even if it operates for 1 minute at a time and 1/100 of the expected cycle rate, it does not matter. Demonstration only means that the design proves that the utility plant and the economics.

I doubt than anyone has anything near to "all the full or near enough full scale hardware".
Right now practically all the investments in commercial fusion is just to prove the physics to get a Q>1, only than we will see the big investors pouring real money into it to solve the other issues as you correctly mentioned. But I doubt anyone will present a ready plant at the same moment when they will announce that they solved the Q>1 physics.

[Skipjack]

This is not a horse race with betting slips. and commercial Fusion is not about a science experiment. This is about practical utility scale machines. Moreover, a demonstration machine only has to show the design in real life. If Helion has all the full or near enough full scale hardware, even if it operates for 1 minute at a time and 1/100 of the expected cycle rate, it does not matter. Demonstration only means that the design proves that the utility plant and the economics.

The balance of the plant too is important, and that can be at scale sufficient to prove the design and make economic and efficiency calculations. Remember, the regulatory agencies have to approve the plant and investors convinced of the return on their money. The divertor life for instance is important for Helion, hence it is what they talked about first if you will notice.

Neverltheless, it is good news. So, any word on a demonstration plant announcement? If not, why not? TAE has a roadmap to theirs, GF has announced theirs.

Helion has been very reserved with talking about future timelines ("forward looking statements") after they got burned after complete lack of investment delayed their plans for years.
They only came out with this info because of some snarky articles (with lazy research) about their perceived lack of progress that have been appearing in various places lately. Plus there are some fusion outfits that are claiming records despite Helion presenting better results with VENTI at the APS/TOFE in 2018. Stuff like that sort of forced their hand. To my understanding, there is a lot more going on there than they have announced so far, but that is what they are willing to talk about right now. They will reveal more details when they are ready to do so.
I think that their very nice progress over the past 2.5 years shows quite well what they are capable of and how quickly they have been moving forward.
I mean, the stats speak for themselves. No other private fusion outfit has achieved 100 million degrees C and their energy recovery is so out there that people have trouble believing it.

As for the size of Trenta, I (think I) can say that it is 30 times the volume of VENTI. Not sure how much more detail I can give about that without stepping on some toes.

And again, I think that for the race to a demonstration plant, we should make a new thread. This one is purely for Q>1 (by any measure too) as per the OP.