ZAP Energy News

[Skipjack]

ZAP has added a how it works section to their website:
https://www.zapenergyinc.com/how-it-works

Fuze-Q is now operational. It is designed to achieve up to one 1MA input current. They still expect to hit Q>1 at 650 kA.
Looks like they added a secondary containment shell to their machines. Those are quite a bit bigger. Not sure if this would affect mass manufacturing and road transport.

[mvanwink5]

I would think the outer containment shell would be concrete since it is not a pressure vessel.

Zap claims site flexibility but they use a thermal cycle so there could be a huge heat load to reject, which usually these days means a cooling tower of some sort. This contrasts to Helion which is not a thermal cycle for fusion to electric power conversion, hence has potentially far lower heat rejection.

However, Zap looks to be targeting thermal plant retrofits.

[Skipjack]

It looks like the outer vessel is some sort of metal that comes in sections that are bolted together on site. There are bolts visible in the video.

[mvanwink5]

It is not needed for radiation; I suspect it is for heat shielding.

[Giorgio]

If they prove the stability of the Sheared Flow phenomena as they increase input current and decrease plasma pinch radius, than we will have a definitive winner for immediate power plant retrofitting.

Due to the higher complexity, direct fusion to electricity solutions will anyhow require much longer times from proof of principle to market installation, but as a fusion thermal generator you really can't go more simple than what ZAP is attempting.

I am really excited to see what results they will get.

[mvanwink5]

Due to the higher complexity, direct fusion to electricity solutions will anyhow require much longer times from proof of principle to market installation, but as a fusion thermal generator you really can't go more simple than what ZAP is attempting.

On the second point, me too!

On the first, wrt complexity, Helion has already demonstrated direct conversion in hardware and further their 2024 goal includes proof of net direct electric power. Still 2024 is a year later than ZAP's 2023 target for net **thermal** power.

2023 is close.

[Skipjack]

The way I see it, Zap has the advantage of much more compact cores that are going to be really cheap to mass produce and ship. As you say, they can likely retrofit thermal plants with relative ease by simply combining the right amount of modules.
Helion's ability to quickly ramp power production from 0 to 100% makes them ideal for replacement of natural gas turbines and combined cycle plants.
I don't think that Helion's machines will need a longer time to get to market as they have tested their direct conversion in over a million shots.
Despite the larger size of the core, a Helion power plant will likely have a smaller overall footprint than a Zap- plant of the same power level.
ZAP in turn can also serve markets that do not require (just) electricity but (also) industrial heat.
Assuming that both will be equally economic, I think that they will serve their own segments of the energy market with relatively little overlap.

One thing that is interesting about Helion and likely also about ZAP is that their power plants get more economic with multiple cores. E.g. Helion can use the same capacitor bank with (I think) up to 6 cores. ZAP might be able to serve even more cores with the same bank if the switches can handle it.
Power equipment and power lines can also be shared.
Both will likely have occasional down times for maintenance. So many installations will have more than one core. That will likely also make bigger plants more economic since they can have fewer cores/MWe.

Either way, we live in interesting times.

[mvanwink5]

Thermal plants need cooling towers, Helion will not. This is a big issue for siting. Helion should be able to locate a plant inside a city.

[Skipjack]

Not all thermal plants have cooling towers. Some are located near a large or running body of water for cooling (e.g. the sea or a river).
That said, I agree that Helion has a siting advantage for new sites. I assume that ZAP is planning to offset the disadvantage by converting existing sites of thermal power plants.

[mvanwink5]

Siting that uses rivers or ocean heat sinks is increasingly more difficult in the US, but in other countries that can vary. Some northern countries will use steam for heating so a thermal plant can take advantage of that.

It would be interesting to see how fast ZAP can proceed with their testing; 2023 is nearly upon us.

[Giorgio]

I don't think that Helion's machines will need a longer time to get to market as they have tested their direct conversion in over a million shots.

Let me rephrase in a different way.
ZAP has only one technological major hurdle to overcome to reach the commercial fusion doorstep, i.e. keeping the Sheared Flow phenomena stable as they increase the power and decrease the pinch radius.

Helion has to solve the following technological hurdles:
1) Prove the fusion process parameters.
2) Prove that those parameter can meet their He3 fuel cycle.
3) Verify the the ability to absorb the neutron out of the cycle.
4) Prove their direct energy recovery in a continuous environment at the 95%+ recovery rate that they have declared.

The first and the second are tough, especially keeping the right balance to minimizes the bremsstrahlung and the synchrotron radiation while pushing the fuel cycle reactions in the right direction.
But according the little data they showed before it seems that they have a clear idea on how to handle it (keeping plasma T <50Kev and high plasma density), so that should be more or less under control (already an amazing result if successful).

Their fuel Cycle is great in theory and simulations, but it has never been realized at the scale they are planning to do, so that theoretical 4% of D+3He side reactions (and the neutron production associated to it) is still a potential cause of concern to me.

But is in the direct conversion where I potentially see the biggest issues, as it needs to be tested with the fusion "soup" that the machine will create at steady state, and until that moment no one really knows if and how it will work.
I might be wrong, but in my opinion the technological breakthrough of being able to build a direct fusion"soup" to energy converter is on the same level as reaching Q>1.

I know we disagree on this, and I sure do hope that you are right and I am wrong as such a reactor like Helion will give us all the energy we need to start our expansion beyond Earth boundaries.

Either way, we live in interesting times.

Indeed we are.

[Skipjack]

Let me rephrase in a different way.
ZAP has only one technological major hurdle to overcome to reach the commercial fusion doorstep, i.e. keeping the Sheared Flow phenomena stable as they increase the power and decrease the pinch radius.

I think they also have to proof that their Tritium breeding will work and that they can do the liquid LiPb waterfall. They also have to ensure an economic lifetime for their electrodes.

The first and the second are tough, especially keeping the right balance to minimizes the bremsstrahlung and the synchrotron radiation while pushing the fuel cycle reactions in the right direction.

But according the little data they showed before it seems that they have a clear idea on how to handle it (keeping plasma T <50Kev and high plasma density), so that should be more or less under control (already an amazing result if successful).

Their fuel Cycle is great in theory and simulations, but it has never been realized at the scale they are planning to do, so that theoretical 4% of D+3He side reactions (and the neutron production associated to it) is still a potential cause of concern to me.

But is in the direct conversion where I potentially see the biggest issues, as it needs to be tested with the fusion "soup" that the machine will create at steady state, and until that moment no one really knows if and how it will work.
I might be wrong, but in my opinion the technological breakthrough of being able to build a direct fusion"soup" to energy converter is on the same level as reaching Q>1.

1, 2) Helion has relatively low Bremsstrahlung losses because of the high Ti to Te ratio. That ratio decreases over the length of the pulse but increases with temperature (it peaks at 17.5 : 1 at 9 keV plasma temperature). They are quite sure they can keep that up.

3) Their neutrons are relatively low energy, below the activation energy of the materials they are planning to use. That said, they will likely have more than 4% of the fusion energy in neutrons since they need (at least initially until there is enough Tritium to decay) to have more D-D reactions than D-He3 reaction to have the fuel cycle close. It is not that big of a deal, but it will likely affect economics a little bit in the first few years.

4) EVERYONE gets hung up on that one. Personally, I take it as a solved problem.
Mind you, the recovery of the fusion energy won't be quite as efficient because some of the fusion energy is lost to X-Rays and neutrons. But the input energy recovery is 95% efficient (rounded down!).
Also note, the machine will never operate at steady state. They will always be pulsed machines. The pulse rate just gets faster for the next generations (1Hz with Polaris, 10 Hz for power plants). And another common misconception is that the FRC "dies" after the compression and that there is just a disorganized plasma that remains. That is not the case. It stays alive and stable long enough for the expanding plasmoid to transfer its energy content to the magnets.

Personally, I see their biggest challenge in increasing the pulse rate to 10 Hz from the current 1/600 Hz. That is a huge jump and has some interesting engineering challenges (pumps, seals, power supply, etc). Though they did have quite high pulse rates with their smallest FRC- system, which made over a 1 billion FRCs.

[Giorgio]

I think they also have to proof that their Tritium breeding will work and that they can do the liquid LiPb waterfall. They also have to ensure an economic lifetime for their electrodes.
{...}
That said, they will likely have more than 4% of the fusion energy in neutrons since they need (at least initially until there is enough Tritium to decay) to have more D-D reactions than D-He3 reaction to have the fuel cycle close.

To create a laminar liquid waterfall is a trivial mechanical design. Their blanket diameter is 3 meter, so also the breeding and separation of the newly bred Tritium is not a concern as we have plenty of literature on both these points since the 90's.

Different will be the situation for Helion that will use a solid blanket where the Tritium migration processes is dependent from quite a large number of variables. There is lot of literature with mixed results as small changes in operating parameters can swing conversion efficiency quite a lot.
That is my concern for them.

1, 2) Helion has relatively low Bremsstrahlung losses because of the high Ti to Te ratio. That ratio decreases over the length of the pulse but increases with temperature (it peaks at 17.5 : 1 at 9 keV plasma temperature). They are quite sure they can keep that up.

I agree. As I said I am not worried too much for point 1 and 2.

4) EVERYONE gets hung up on that one. Personally, I take it as a solved problem.

I am happy that I am not he only one that sees it as an issue, and I hope we are all wrong about it, but I still lack the data to change idea on this point. As I said, I consider reaching this technological ability of out-most importance for our civilization.

Also note, the machine will never operate at steady state. They will always be pulsed machines. The pulse rate just gets faster for the next generations (1Hz with Polaris, 10 Hz for power plants).

Even pulsed machine have a steady state.That is the state when the value of all the internal variables reach an equilibrium due to the continuous energy fluxes from the sequence of pulses. Think of it like the "warm up" phase of an internal combustion engine. The difference in behavior from the cold engine to the steady state (equilibrium of all Variables) can be quite big, and the same apply to Helion and ZAP.
Zap advantage also in this case it the use of the molten blanket that limits the variables to a small part of the machine. In Helion all the major components are inside the machine and are participant/subjected to the changes of the system as it evolves.

Personally, I see their biggest challenge in increasing the pulse rate to 10 Hz from the current 1/600 Hz. That is a huge jump and has some interesting engineering challenges (pumps, seals, power supply, etc). Though they did have quite high pulse rates with their smallest FRC- system, which made over a 1 billion FRCs.

Yes, in truth I also think that this is going to be challenging for both, but is also a problem that can be solved by dividing the various parts into smaller (even if less efficient) subsystems. But anyhow we have plenty of experience for seals pumps and power management in real world that i do not consider it a too much difficult issue to be solved for both companies.

[Munchausen]

A good and enlightening debate!

Maybe a question about whether the glass is half empty or half full, but:

"one technological major hurdle to overcome to reach the commercial fusion doorstep, i.e. keeping the Sheared Flow phenomena stable as they increase the power and decrease the pinch radius."

.....We better assume that this is what is about to happen. That is what has happened to every fusion undertaking since Oliphant charachterized the fusion reactions in the twenties.

40 million dollars down the sewer. Still 40 million better spent than building the pyramids or invanding the Ukraine.

The more glad we will be when the success finally arrives.

[Giorgio]

.....We better assume that this is what is about to happen. That is what has happened to every fusion undertaking since Oliphant charachterized the fusion reactions in the twenties.

Yes, you are totally correct. Scaling-up instabilities has been the show-stopper of every major/medium/small fusion idea of the last century.
Still, the amount of knowledge we learned from those failure is what really pushed the boundaries to enable new visions like ZAP and Helion.
So I really want to believe that one of them will succeed. I want to see a fusion reactor in my life, and I do not have another 100 years to wait.