arxiv.org: a pre-print source, this is not peer-reviewed yet. So, until other papers refer to this paper, it has low significance in the literature. The paper has references to other papers and to previous corpus of knowledge on the subject, which is good. However, this paper is based on simulations only.
Crucially, the scheme identified here does not negatively impact electricity production, and is also compatible with the challenging tritium breeding requirements of fusion power plant design because (n, 2n) reactions of 198Hg drive both transmutation and neutron multiplication
Monte Carlo transport calculations show that neutrons produced in a tokamak power plant can convert the abundant isotope 198Hg to stable 197Au via the (n,2n) channel, yielding several tonnes of gold per plant-year without compromising the tritium breeding ratio.
The decommissioned blanket material would increase in value, and the Mercury-198 in the blanket doesn’t majorly impact its effectiveness in transmuting lithium to tritium.
The “worst” gold isotope half-life is less than a year, so only a modest cool-down is needed for the output:
197Au to be Class 7 when activity concentration is > 2700 pCi/g, which is reached after 13.7 years for the initial concentration listed.
An even more stringent constraint can be applied for any gold that will be regularly handled by the general population. As a highly conservative requirement, we can stipulate that this gold must be less radioactive than a banana. Due to 40K content, bananas have an activity of ∼ 3520 pCi/kg, or about 420 pCi for a single banana. To meet this requirement, a troy ounce of gold with the initial isotope mix shown in Table 2 must sit for about 17.7 years to be below a banana equivalent level of activity.
What strikes me here with this paper is the suggested liquid blanket, so this would be a kin of D-T Fusion MSR. We now have two proposed technologies behind being able handle hot radioactive liquids.
The safe level isn’t that important, because the gold can be put into an ETF investment vehicle, which is a substantial enough demand for gold. National reserves (the vast majority of gold demand) too are long term holders.
2t/GWhth is a huge amount. While the best case economics for fusion is 30c/kwh cost = $3m/Gwhe, that would be 3GWhth = 6T of gold. Even at $45/oz (1/100th of current value) that would be $8m/Gwhe revenue, and would likely be able to sell electricity at market rates as the “waste product”, or not even bother with the expense/complexity of electricity generation.
Look at the gold price for the last 10 years, it’s steadily rising. We keep producing more electronics that need gold. At the same time some gold is lost because not in all tech it can be easily recycled. On top of that gold mining is becoming more expensive because a lot of easily accessible gold has been mined out.
So even if this technology could create additional gold in the future it probably won’t out scale the growing demand.
It also helps that we’re talking about rather dense nuclei too. So it’s not just a neutron absorbing blanket, but a rather high-performing one at that. Which you need to convert fusion outputs to heat and power anyway. And gold is soluble in mercury anyway, so extraction is already a known (albeit incredibly dangerous) process. Win-win.
yielding several tonnes of gold per plant-year
Mother of god that’s a lot to magic-up outta nowhere. At first I thought this would disrupt the market, but it looks like yearly global gold production is around 3000 tons a year. So it would take a lot of reactors to impact the gold market, so… yeah. Reactors really could start paying for themselves.
arxiv.org: a pre-print source, this is not peer-reviewed yet. So, until other papers refer to this paper, it has low significance in the literature. The paper has references to other papers and to previous corpus of knowledge on the subject, which is good. However, this paper is based on simulations only.
The decommissioned blanket material would increase in value, and the Mercury-198 in the blanket doesn’t majorly impact its effectiveness in transmuting lithium to tritium.
The “worst” gold isotope half-life is less than a year, so only a modest cool-down is needed for the output:
What strikes me here with this paper is the suggested liquid blanket, so this would be a kin of D-T Fusion MSR. We now have two proposed technologies behind being able handle hot radioactive liquids.
Banana for scale!
I understood some of those words. Nevertheless, thanks for providing some crucial context.
The safe level isn’t that important, because the gold can be put into an ETF investment vehicle, which is a substantial enough demand for gold. National reserves (the vast majority of gold demand) too are long term holders.
2t/GWhth is a huge amount. While the best case economics for fusion is 30c/kwh cost = $3m/Gwhe, that would be 3GWhth = 6T of gold. Even at $45/oz (1/100th of current value) that would be $8m/Gwhe revenue, and would likely be able to sell electricity at market rates as the “waste product”, or not even bother with the expense/complexity of electricity generation.
Wouldn’t the constant stream of new gold tank the market value?
Look at the gold price for the last 10 years, it’s steadily rising. We keep producing more electronics that need gold. At the same time some gold is lost because not in all tech it can be easily recycled. On top of that gold mining is becoming more expensive because a lot of easily accessible gold has been mined out.
So even if this technology could create additional gold in the future it probably won’t out scale the growing demand.
I can’t imagine it would be any different than a new gold mine opening up somewhere in the world.
It also helps that we’re talking about rather dense nuclei too. So it’s not just a neutron absorbing blanket, but a rather high-performing one at that. Which you need to convert fusion outputs to heat and power anyway. And gold is soluble in mercury anyway, so extraction is already a known (albeit incredibly dangerous) process. Win-win.
Mother of god that’s a lot to magic-up outta nowhere. At first I thought this would disrupt the market, but it looks like yearly global gold production is around 3000 tons a year. So it would take a lot of reactors to impact the gold market, so… yeah. Reactors really could start paying for themselves.
Yeah, that should help them with their capital, storage costs and Hg procurement costs.
Now back to the energy generation…