More Helion Energy news....

[mvanwink5]

Good. I can't see anything that would slow them down like long lead time metal forgings like GF has. There is still a lot of work, but the divertor longevity was super news. Maybe that was what they were waiting for?

[Skipjack]

We will see. I am confident that they will move faster now than they did in the past because they now have more people and money. But at the same time their challenges are harder too. I would estimate around 3 years until the next prototype's campaign is complete (last one was 2.5 from start of construction).

[RERT]

Out of nothing really: I hear tell that TAE sees its FRC plasma stability rise with temperature, therefore p11B isn’t as daft as it might seem.

That sounds like physics not technology.

Isn’t Helion also an FRC? Does similar hope for p11B apply to them?

Neutronic power will be considered evil as soon as someone makes p11B work. (Discuss)

[mvanwink5]

Helion has the issue with divertors due to plasmoid method of heating. TAE uses neutral beam heating so their divertors are not exposed every cycle... just the cycle to get the plasmoid established. That does not mean the Helion might find better magnetic shielding in the future, it just means that it is unclear at present from my own limited insights. So it is a technical concern.

[Skipjack]

Helion's and TAE's reactors have some things in common but they are quite different. Both merge two FRC plasmoids into a single FRC in a central chamber.
The differences are:
1. Helion accelerates their plasmoids to higher speeds.
2. TAE keeps their merged plasmoids in a semi- stable steady state after merging. Helion compresses them when they merge in the central chamber with a very strong magnetic pulse.
3. TAE keeps replenishing their merged FRC with neutral beam injection. Helion lets them dissipate after the extreme compression (pulsed).
As far as I am aware, both have roughly have the same energy confinement time but have different plasma lifetimes, pressures and temperatures.

There are benefits and disadvantages to both. One could imagine TAEs design as a pot without a lid that is slowly boiling on the stove.
TAE has to constantly add heat to keep it boiling and eventually replenish the water.
Helion's pot is more like a pressure cooker that boils really quickly (until it blows steam). Then they put a new pot with cold water on the stove and start over again.
I am not aware of Helion observing higher plasma stability at higher temperatures. The thing is that Helion does not really need long plasma lifetimes, due to the pulsed nature of their reactor design. Helion's challenge is to have strong enough magnetic fields to quickly compress and heat the plasma. TAE's challenge is to keep their plasma alive and hot for long enough.

So far it looks to me like Helion's reactor core will be MUCH smaller than TAE's. The former will be around the length of an oversized shipping container, including direct conversion technology. TAE's PB11 machine is going to be 80 meters in length. So Helion can build their reactors off site and ship them in one piece, maybe even with enclosure, shielding, etc. TAE will have to assemble their reactor core on site and they will need some fairly large buildings too. That drives up overnight costs. I mean look at size of that thing on page 65 here: https://www.nrc.gov/docs/ML2109/ML21090A288.pdf

Helion also has a more efficient (~95%) energy recovery and conversion scheme due to the pulsed nature of their reactor. They can vary energy output and load follow by varying pulse frequency. They should even be able to replace gas peaker plants, which would allow them to charge a lot more for the same amount of power produced (up to 200 USD/MWh).
To the best of my understanding, TAE can not do any of that. Their direct conversion (if they manage to develop it), will be interesting and they currently estimate it to be only about 30% efficient. That also means that they have more waste heat to deal which requires more cooling equipment. Helion's reactor core essentially produces the same amount of waste heat as a diesel train engine. So it is quite simple to cool that on a small footprint.
On the other hand TAE's reactor is going to produce about 350 MWe/core while Helion's will only produce 50MWe. So multiple Helion cores would be needed to produce the same amount of energy. The waste heat can also be used for things like industrial and residential heating, so it is not completely wasted.

As for neutrons:
Helion's reactor only releases 5% of it's energy as neutrons. That is quasi- aneutronic. And mind you, those neutrons can be used to do some work as well (breed Tritium for more He3 and make a few extra MeV at the breeding blanket).
Also note that while PB11 is much more aneutronic than D-D-He3, they still produce some via some side reactions. Plus they have a lot of X- Rays to deal with due to the much higher temperatures involved with PB11.

Personally, I think that the market is big enough for multiple reactor designs and we will see several of the fusion companies succeed in different niches of the market. There are a lot of different fission reactor designs out there. So why would fusion be any different?

[mvanwink5]

So far it looks to me like Helion's reactor core will be MUCH smaller than TAE's.

As far as I can see all your points are good.

Minimum investment also means quicker prototype build. It also means there could be military applications such as ships. Might be a good time to get the NRL interested in Helion?

[Skipjack]

I somehow missed that press release earlier:
Fusion Energy Startup Helion Energy Closes Latest Funding Round at $1.25B Valuation

https://www.helionenergy.com/articles/f ... valuation/

[Skipjack]

Learned something interesting today. Helion's final, commercial scale reactor will not have 40 Tesla magnetic fields. For me that always was an area of concern since they plan to use non super conducting magnets. Without those, 40 Tesla are very hard (though not entirely impossible, since they are pulsed and the pulses are very short).
The 40 Tesla goal was mainly for the benefit of ARPA-E, which had a certain set of requirements like thermal energy conversion rather than the much more efficient direct conversion. Instead Helion is aiming for a higher repetition rate but with a lower gain. The lower gain (again) is not a problem thanks to a 95% efficient direct conversion system. I don't have details about the final magnet strength that they are going for, but I presume it will be in the 20 Tesla range (which is what they planned for with VENTI). I hope to have more info on that soon, if they decide to release that information yet. I will post an update then.

[Giorgio]

That's quite interesting as 20 Tesla is ready doable.
The machine will probably be me much bigger in size but for a first generation (and ground based machine) this is not an issue at all.

I still do have lot of doubts and worries on this theoretical 95% efficiency direct energy conversion and on how they will manage all the theoretical losses due to the energy fluxes re-circulation into the machine and in the energy banks.

[Skipjack]

That's quite interesting as 20 Tesla is ready doable.
The machine will probably be me much bigger in size but for a first generation (and ground based machine) this is not an issue at all.

I think that there are some opportunities in shipping as well. There was a recent study that looked at Tokamaks and concluded that even those were feasible for shipping. Helion's reactor would be much more compact and would not need a steam plant.

I still do have lot of doubts and worries on this theoretical 95% efficiency direct energy conversion and on how they will manage all the theoretical losses due to the energy fluxes re-circulation into the machine and in the energy banks.

There is a lot of precedence in regenerative braking for electric cars, which is already very efficient, despite being mechanical with friction and all that.
Some of the technology developed for cars likely benefited Helion as well. E.g. today's IGBT switching is super efficient compared to what was available just a couple of decades ago.

[Giorgio]

There is a lot of precedence in regenerative braking for electric cars, which is already very efficient, despite being mechanical with friction and all that.
Some of the technology developed for cars likely benefited Helion as well. E.g. today's IGBT switching is super efficient compared to what was available just a couple of decades ago.

Indeed some of the newly developed electrical technologies for electrical cars will benefit Helion power recovery, but if their energy recovery plan is the same that they presented in the various arpa-e papers than I have strong doubts that they will ever reach a 95% energy recovery efficiency for the whole energy flux system. If they get to 75% global round trip efficiency I will already be impressed.

[Skipjack]

There is a lot of precedence in regenerative braking for electric cars, which is already very efficient, despite being mechanical with friction and all that.
Some of the technology developed for cars likely benefited Helion as well. E.g. today's IGBT switching is super efficient compared to what was available just a couple of decades ago.

Indeed some of the newly developed electrical technologies for electrical cars will benefit Helion power recovery, but if their energy recovery plan is the same that they presented in the various arpa-e papers than I have strong doubts that they will ever reach a 95% energy recovery efficiency for the whole energy flux system. If they get to 75% global round trip efficiency I will already be impressed.

Their ARPA-E experiments and papers were targeted at ARPA-E, which had specific requirements. Also mind you, they did not stand still but have been improving their recovery technology constantly, since it is a core concept of their design.
I mean, this is essentially an electric generator without any moving parts, brushes, etc. The plasma acts like the rotor and the compression and acceleration magnets are the stator. Electric generators today are actually up to 99%(!) efficient. So it seems plausible that theirs would be in the same range (and 95% is actually slightly below that).

[Giorgio]

Their ARPA-E experiments and papers were targeted at ARPA-E, which had specific requirements. Also mind you, they did not stand still but have been improving their recovery technology constantly, since it is a core concept of their design.
I mean, this is essentially an electric generator without any moving parts, brushes, etc. The plasma acts like the rotor and the compression and acceleration magnets are the stator. Electric generators today are actually up to 99%(!) efficient. So it seems plausible that theirs would be in the same range (and 95% is actually slightly below that).

I still need to read any official experimental data and details about their direct recovery process, and while I generally agree on your point that the Plasma will act like a rotor, the truth is that the process is inherently different and exponentially more complicated from a simple electric engine, so is very hard to transpose an existing electrical engine technology to a "yet to be tested" (as far as I know) direct energy conversion system.

Also worth considering that due to the slow repetition rate all this energy need to be converted, smoothed and stored into battery packs before its next use. This will also give quite a big cut to the round trip global efficiency of the energy recirculation.

[Skipjack]

I still need to read any official experimental data and details about their direct recovery process, and while I generally agree on your point that the Plasma will act like a rotor, the truth is that the process is inherently different and exponentially more complicated from a simple electric engine, so is very hard to transpose an existing electrical engine technology to a "yet to be tested" (as far as I know) direct energy conversion system.

Also worth considering that due to the slow repetition rate all this energy need to be converted, smoothed and stored into battery packs before its next use. This will also give quite a big cut to the round trip global efficiency of the energy recirculation.

The recovery process has of course been tested. It is actually over 95% efficient, but they rounded it down to 95%. That is first hand information.
Part of the reason why it works is because of the extremely high beta of the plasma ~1.
You are correct that repetition rate is very important for overall system efficiency. That is why they are working on increasing the repetition rate to 1 Hz for the next prototype and possibly higher than that later.
That said, they store the energy in capacitors between shots, not batteries. Capacitors are very efficient (near 100% today).

[natebrau]

https://www.eetimes.com/helion-energy-a ... milestone/

Interesting article on Helion. They're getting more press, must be a good sign.