5 ms·

Helion hasn't published the triple product results for their latest Trenta reactor, but for the previous Venti they achieved a triple product of ~10^19 keV.s/m^

by jjk166 5y ago

Helion hasn't published the triple product results for their latest Trenta reactor, but for the previous Venti they achieved a triple product of ~10^19 keV.s/m^3 at an ion temperature of 2 keV. The Trenta reactor has achieved an ion temperature of 9 keV. For D-T fusion, you need a triple product of about 3x10^21 kev.s/m^3 at 10 keV. For the D-He reaction that helion intends to use, they need to achieve a similar triple product at 50 keV. So it looks like they're still 2-3 orders of magnitude off from where they need to be to achieve ignition. Their neutron production rate is comparable to industrial fusors at ~10^11 n/s, which while useful as neutron sources are nowhere near producing net power. Compare this with tokamaks that have achieved a triple product around 1.5x10^21 keV.s/m^3, or about half of what they need to achieve ignition. While it's possible that helion has made improvements to ion density and confinement allowing them to achieve a significantly higher triple product and close the gap to power production, I see no reason why a company looking for investment would hide such a result, especially while putting out press releases celebrating other milestones. I doubt they're anywhere near the point where an economical plant could even be considered, though I'd love to be proven wrong.

bloudermilk 5y ago
They're not exactly looking for investment, are they? With close connections to investors with deep pockets, in a race to commercialize fusion, it's not exactly surprising that they would keep their cards close to their chest.
- jjk166 5y ago
  This is literally an article about them closing a round of investment. What exactly would they gain from keeping this particular card close to their chest?
  - bloudermilk 5y ago
    The real question to ask is, what would they gain from revealing it?
  - nabakin 5y ago
    An advantage over competitors is my first thought. That being said, it seems sketchy to me too. You always have to take these extraordinary scientific claims with a big grain of salt
pmarreck 5y ago
So basically it's a low probability win with an extremely big payoff and the added difficulty of a general lack of transparency to the public (but perhaps not to angel or series A/B/C investors), same as any startup investment.
- jjk166 5y ago
  If you don't slap some numbers on there, anything could be described as a low probability win with an extremely big payoff.
  - pmarreck 5y ago
    well if it goes by other startups it’s something like, given 10 startup investments… 8 crater 1 breaks even 1 does a moonshot
levi_n 5y ago
IIRC, ITER wont be fully operational until 2035, and will only ever be a research reactor. Even if it can produce net energy (I'm skeptical), it's cost and size are way up there. Even if Helion is behind the tokamaks, perhaps this play is more about reaching an economically viable reactor design? Not first to fusion, but first to scalable fusion?
- jjk166 5y ago
  Achieving fusion is a necessary step along the road to achieving economically viable fusion. They have a long ways to go before they achieve the easier of the two steps.
jiggawatts 5y ago
Something I consider to be a "red flag" in the press releases of any new kind of energy source, power plant, or engine is when they start talking about the potential applications of something fungible like electricity. E.g.: In the Tech Crunch article linked elsewhere in this discussion there is this quote: "Helion’s CEO speculates that its first customers may turn out to be data centers" Do you know what else a 50MW generator could be used for? Anything. Anything that electricity is used for now. Why talk about things we all already know? Why talk about specific applications? It's like a car company advertising that their new engine could be used to drive to Starbucks to get a coffee. Once you notice this pattern, you'll see it everywhere in Free Energy / LENR circles...
- tlb 5y ago
  Eventually a power source can power anything, but choosing good first customers is important. Usually, v1 of the product is expensive and flaky. So you need first customers who are willing to pay extra for the privilege of being early adopters, or for PR value. Data centers seem like a good bet here. As you get better at mass producing the machines, the cost will come down and you can make money selling power to the grid at much lower prices.
  - jiggawatts 5y ago
    Data centers absolutely do not go for unproven and flaky electricity sources! They go for the most boring, proven, and even downright inefficient sources. They need robustness above all things. Untested nuclear reactors (fusion or fission) are about as far away as possible from what they want as it is possible to get. Not to mention that many data centres are bang in the middle of high density urban areas, or at least reasonably close to them, typically in some industrial area on the outskirts of town. No council in their right mind would approve any kind of nuclear power without years and years of environmental impact studies, justifications, reams of paperwork, etc... You might argue that it's "safe", but the bureaucrats won't care about your opinion. They'll be worried about perception in an era where people set communication towers on fire because they want to stop 5G "radiation". Fusion is precisely the kind of technology that is best implemented as base load in a standard power plant type configuration. Far away from big cities and scaled for efficiency. It makes zero sense to plop something this esoteric down somewhere downtown to occasionally power a data centre during a rare power outage. This "suggested" use case is 100% intended to appeal to people like you, the "YC News" crowd type. It is absurd on its face. Hilariously improbable. But it sounds cool and it got you talking, so a successful marketing trick, I suppose.
Veedrac 5y ago
Helion is a non-ignition fusion reactor. They aim to avoid the need for ignition by having efficient energy recapture. The website goes into more detail, and the prototypes have demoed this capability.
- jjk166 5y ago
  The lawson criterion is the point at which the plasma is heated by fusion faster than it is cooled by losses. It is a lower threshold than ignition. Even without ignition, you still need to achieve it to produce net power. Ironically, their efficient method of energy capture actually makes their job harder than for a thermal system where heat losses due to bremsstrahlung and neutron heating are partially recovered; indeed this is the output for a conventional fusion reactor. For helion, only the energy of the plasma is harvested and thus they must exceed breakeven by enough to not just maintain but to heat the plasma by some economically useful amount.
  - Veedrac 5y ago
    I'm confused. I thought the Lawson criterion was the threshold for ignition, and Google seems to be backing me up. Am I missing a subtlety here?
    - jjk166 5y ago
      Google is oversimplifying. The lawson criterion is defined to be the point where heat production by the plasma equals heat loss. For tokamaks (and other magnetic confinement fusion reactors where the confinement time is very long) reaching the lawson criterion is basically all you need to do to achieve ignition - once the plasma is being heated by fusion reactions faster than it is losing heat, it will very rapidly reach the point where it ignites with no further external input. For short duration fusion (ICF, Magnetized target, Helion, etc) you can exceed the lawson criterion and thus produce gain, but the plasma may still not be long enough lived for the fusion to actually induce more fusion (which is the actual ignition point).
      - 5y ago
lambdatronics 5y ago
>For the D-He reaction that helion intends to use, they need to achieve a similar triple product at 50 keV The triple product is 16x higher for D-He3.[0] They also need to get D-D reactions going to produce the He3. The triple product for that is 30x the D-T value. (Yeah, you could run the D-D reaction at a loss or at barely-breaking-even I guess). They're talking about letting the T from the D-D reaction decay to produce more He3. Tritium has a half-life of 12 years, so in steady-state, there is about 20x the annual tritium production sitting in storage. That's a massive amount -- a 1GW D-T reactor would use something like 50kg of T in a year, so that's about 1 tonne of T. (Just getting some rough approximation.) Even if you scale it down to 50 MW, that's still 50kg. It's a major radioactive hazard. >I see no reason why a company looking for investment would hide such a result Exactly. Fusion companies tend to trumpet their successes from the rooftop. [0] https://en.wikipedia.org/wiki/Nuclear_fusion#Neutronicity,_confinement_requirement,_and_power_density https://en.wikipedia.org/wiki/Nuclear_fusion#Neutronicity,_c...

by jjk166 5y ago

bloudermilk 5y ago

They're not exactly looking for investment, are they? With close connections to investors with deep pockets, in a race to commercialize fusion, it's not exactly surprising that they would keep their cards close to their chest.

jjk166 5y ago
This is literally an article about them closing a round of investment. What exactly would they gain from keeping this particular card close to their chest?
- bloudermilk 5y ago
  The real question to ask is, what would they gain from revealing it?
- nabakin 5y ago
  An advantage over competitors is my first thought. That being said, it seems sketchy to me too. You always have to take these extraordinary scientific claims with a big grain of salt

pmarreck 5y ago

So basically it's a low probability win with an extremely big payoff and the added difficulty of a general lack of transparency to the public (but perhaps not to angel or series A/B/C investors), same as any startup investment.

jjk166 5y ago
If you don't slap some numbers on there, anything could be described as a low probability win with an extremely big payoff.
- pmarreck 5y ago
  well if it goes by other startups it’s something like, given 10 startup investments… 8 crater 1 breaks even 1 does a moonshot

levi_n 5y ago

IIRC, ITER wont be fully operational until 2035, and will only ever be a research reactor. Even if it can produce net energy (I'm skeptical), it's cost and size are way up there. Even if Helion is behind the tokamaks, perhaps this play is more about reaching an economically viable reactor design? Not first to fusion, but first to scalable fusion?

jjk166 5y ago
Achieving fusion is a necessary step along the road to achieving economically viable fusion. They have a long ways to go before they achieve the easier of the two steps.

jiggawatts 5y ago

Something I consider to be a "red flag" in the press releases of any new kind of energy source, power plant, or engine is when they start talking about the potential applications of something fungible like electricity. E.g.: In the Tech Crunch article linked elsewhere in this discussion there is this quote: "Helion’s CEO speculates that its first customers may turn out to be data centers" Do you know what else a 50MW generator could be used for? Anything. Anything that electricity is used for now. Why talk about things we all already know? Why talk about specific applications? It's like a car company advertising that their new engine could be used to drive to Starbucks to get a coffee. Once you notice this pattern, you'll see it everywhere in Free Energy / LENR circles...

tlb 5y ago
Eventually a power source can power anything, but choosing good first customers is important. Usually, v1 of the product is expensive and flaky. So you need first customers who are willing to pay extra for the privilege of being early adopters, or for PR value. Data centers seem like a good bet here. As you get better at mass producing the machines, the cost will come down and you can make money selling power to the grid at much lower prices.
- jiggawatts 5y ago
  Data centers absolutely do not go for unproven and flaky electricity sources! They go for the most boring, proven, and even downright inefficient sources. They need robustness above all things. Untested nuclear reactors (fusion or fission) are about as far away as possible from what they want as it is possible to get. Not to mention that many data centres are bang in the middle of high density urban areas, or at least reasonably close to them, typically in some industrial area on the outskirts of town. No council in their right mind would approve any kind of nuclear power without years and years of environmental impact studies, justifications, reams of paperwork, etc... You might argue that it's "safe", but the bureaucrats won't care about your opinion. They'll be worried about perception in an era where people set communication towers on fire because they want to stop 5G "radiation". Fusion is precisely the kind of technology that is best implemented as base load in a standard power plant type configuration. Far away from big cities and scaled for efficiency. It makes zero sense to plop something this esoteric down somewhere downtown to occasionally power a data centre during a rare power outage. This "suggested" use case is 100% intended to appeal to people like you, the "YC News" crowd type. It is absurd on its face. Hilariously improbable. But it sounds cool and it got you talking, so a successful marketing trick, I suppose.

Veedrac 5y ago

Helion is a non-ignition fusion reactor. They aim to avoid the need for ignition by having efficient energy recapture. The website goes into more detail, and the prototypes have demoed this capability.

jjk166 5y ago
The lawson criterion is the point at which the plasma is heated by fusion faster than it is cooled by losses. It is a lower threshold than ignition. Even without ignition, you still need to achieve it to produce net power. Ironically, their efficient method of energy capture actually makes their job harder than for a thermal system where heat losses due to bremsstrahlung and neutron heating are partially recovered; indeed this is the output for a conventional fusion reactor. For helion, only the energy of the plasma is harvested and thus they must exceed breakeven by enough to not just maintain but to heat the plasma by some economically useful amount.
- Veedrac 5y ago
  I'm confused. I thought the Lawson criterion was the threshold for ignition, and Google seems to be backing me up. Am I missing a subtlety here?
  - jjk166 5y ago
    Google is oversimplifying. The lawson criterion is defined to be the point where heat production by the plasma equals heat loss. For tokamaks (and other magnetic confinement fusion reactors where the confinement time is very long) reaching the lawson criterion is basically all you need to do to achieve ignition - once the plasma is being heated by fusion reactions faster than it is losing heat, it will very rapidly reach the point where it ignites with no further external input. For short duration fusion (ICF, Magnetized target, Helion, etc) you can exceed the lawson criterion and thus produce gain, but the plasma may still not be long enough lived for the fusion to actually induce more fusion (which is the actual ignition point).
    - 5y ago

lambdatronics 5y ago

>For the D-He reaction that helion intends to use, they need to achieve a similar triple product at 50 keV The triple product is 16x higher for D-He3.[0] They also need to get D-D reactions going to produce the He3. The triple product for that is 30x the D-T value. (Yeah, you could run the D-D reaction at a loss or at barely-breaking-even I guess). They're talking about letting the T from the D-D reaction decay to produce more He3. Tritium has a half-life of 12 years, so in steady-state, there is about 20x the annual tritium production sitting in storage. That's a massive amount -- a 1GW D-T reactor would use something like 50kg of T in a year, so that's about 1 tonne of T. (Just getting some rough approximation.) Even if you scale it down to 50 MW, that's still 50kg. It's a major radioactive hazard. >I see no reason why a company looking for investment would hide such a result Exactly. Fusion companies tend to trumpet their successes from the rooftop. [0] https://en.wikipedia.org/wiki/Nuclear_fusion#Neutronicity,_confinement_requirement,_and_power_density https://en.wikipedia.org/wiki/Nuclear_fusion#Neutronicity,_c...