2.01410177811 u = 3.34449439340696e-24 g deuterium
3.01604928 u = 5.008267217094e-24 g tritium
17.6 MeV = 7.832863e-19 kWh energy
Divide through, and you will see that you need 4.27 ug/kWh of deuterium, and 6.39 ug/kWh of tritium.
A random source [1] says that New York will use 50.6 TWh per year by 2027. That would require ~216 kg/yr of deuterium and ~323/yr kg of tritium.
This is all assuming 100% efficiency. A quick read suggests 50% efficiency might be practical, so double those quantities.
Also, i could easily have messed up that calculation somewhere, so please do check it!
[1] https://www.buildingcongress.com/advocacy-and-reports/report...
Isn't that going to cause a serious problem if it requires 323Kg/yr of tritium just to power New York City?
[1] https://www.sciencedirect.com/topics/earth-and-planetary-sci...
https://en.wikipedia.org/wiki/Tritium#Production
And there's not much of it:
> According to a 1996 report from Institute for Energy and Environmental Research on the US Department of Energy, only 225 kg (496 lb) of tritium had been produced in the United States from 1955 to 1996.[a] Since it continually decays into helium-3, the total amount remaining was about 75 kg (165 lb) at the time of the report.
Tritium however is far more rare with only trace amounts of it being available within nature and barely more than a kg produced per year. Producing the 100s of kgs required per year still seems to be an unsolved problem, although my quick searching shows there's a couple viable solutions for it.
Though in practice enough will be lost that probably they'll still be somewhat net consumers-- just not nearly to the extent predicted by a simple thermodynamic model.
Still, even if fusion becomes a net producer of tritium, the whole tritium-is-hard-to-get problem will likely be a constraint that we'll be fighting as we ramp up use of fusion power in the future.
i.e. it's completely harmless unless you eat it.
They spent a few hours covered in dust on their coats, and did a bunch of subsurface skin damage which manifested as third degree burns. Sepsis, not radiation poisoning, generally killed them.
FWIW, tritium and a phosphor granule encapsulated in glass microspheres have been developed for self-illuminating runway paint, but again, no one really uses it because tritium is stupid expensive, and again, it' loses half its brightness in only a decade.
On the other hand, I've been told that Trijicon will replace their tritium gun sights for the lifetime of the original owner. I plan to live long enough to cost them money...
We'll all be using RDSs by then ;) ?
> ...I've been told that Trijicon will replace their tritium gun sights for the lifetime of the original owner.
I didn't know this, thanks.
Which I'm going to watch, because even though everything I hear about this company gives me insane Theranos vibes... Well, if they pull it off... They might light a bulb with fusion in my lifetime.
(And I though I had seen a similar segment on "Answer with Joe", but I can't find it.)
None of those would be opposable source, of course - there won't be any until they open a plant, publish data, etc...
In the meantime, I see a hype cycle brewing, and it makes me a bit uncomfortable - but, we'll see.
I'm not sure how tokomaks are expected to work; do you just add lithium and expect the tritium to get where it needs to go to keep the reaction going, or do you actively remove gases from vessel, filter out the tritium, and re-use it as fuel?
Either way, I don't imagine it'd be too hard to recapture the stuff.