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Old 02-22-2018, 06:22 PM   #21
trechriron
 
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Default Re: [Spaceships] Antimatter Factory

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...so that's roughly 43 thousand years.
Which is not practical. So, why would we have anti-matter plasma torches without anti-matter production? I guess you build some giant solar powered monster station on Mercury and ship the fuel everywhere? :D

Huh. I'm going to keep my stats. Working at 10x the rate listed in Munin's table, I can refine 50K of ambH2 in 1000 hours (about 42 days). Not exactly as efficient as I would imagine but certainly reasonable from a "make fuel as we need it" - in a quasi-realistic TL10 universe.

I feel like we could use a real Anti-Matter Factory that is configurable to setting "switches". Maybe a switch like "super efficient anti-matter production"?
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Old 02-22-2018, 06:39 PM   #22
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Default Re: [Spaceships] Antimatter Factory

Even 50% efficient isn't possible. So going beyond that is already fully into superscience. But dials for plausible, technically possible, order of magnitude superscience, and gonzo technobabble superscience is always a good idea, IMO too.

I always assumed antimatter production is for when energy is free and needs to be "moved". Though really for when no other fuel would work. Such as for superscience drives or realistic drives where performance is needed and money is no object... like some military vehicles.
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Old 02-22-2018, 07:43 PM   #23
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Default Re: [Spaceships] Antimatter Factory

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Even 50% efficient isn't possible. So going beyond that is already fully into superscience. But dials for plausible, technically possible, order of magnitude superscience, and gonzo technobabble superscience is always a good idea, IMO too.
Eeeeh... >50% would be limited superscience, in my amateur opinion. The entire existence of the problem of baryon asymmetry suggests that it at least was possible to produce unequal amounts of matter and antimatter at some point in time.

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I always assumed antimatter production is for when energy is free and needs to be "moved". Though really for when no other fuel would work. Such as for superscience drives or realistic drives where performance is needed and money is no object... like some military vehicles.
This is pretty much true, yeah. If you need to refuel en-route, you don't use an antimatter rocket, you use a fusion rocket and tank up on remass twice as often.
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Old 02-22-2018, 08:19 PM   #24
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Default Re: [Spaceships] Antimatter Factory

What is ambH2?
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Old 02-22-2018, 08:32 PM   #25
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Default Re: [Spaceships] Antimatter Factory

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What is ambH2?
antimatter-boosted H₂ (hydrogen).
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Old 02-22-2018, 10:02 PM   #26
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Default Re: [Spaceships] Antimatter Factory

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Eeeeh... >50% would be limited superscience, in my amateur opinion. The entire existence of the problem of baryon asymmetry suggests that it at least was possible to produce unequal amounts of matter and antimatter at some point in time...
Whatever caused the ever so slight initial asymmetry has not been shown in modern antimatter production, so it must be negligible for our purposes. 50% antimatter production would require literal perfect 100% efficiency due to the other half being matter production.
Some things can approach near perfect efficiencies, but many technologies simply can't without assuming superscience or other major hand-waving.
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Old 02-22-2018, 10:03 PM   #27
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Default Re: [Spaceships] Antimatter Factory

The problem with antimatter is that it is that there really isn't any reason to use it. If you really need a highly efficient fuel, just use a pure He-3 mixture, the products of which can be converted very efficiently into propulsion. Since 1 gram of antimatter possesses the same cost of 1 metric ton of He-3 in most settings, you are just better off using He-3. D-He-3 mixes never work out well because the D burns at much lower temperatures and pressures than He-3 (if you look at the fusion rates, the temperature/pressure required to burn 1 He-3:1 D will end up burning around 200 D, so what you end up with is all of the D burning off, leaving a mixture with a proportion of 5 He-3:1 T:1 p:1 n).

If you really want to make antimatter affordable though, you need to make energy very cheap and the process very efficient. Right now, the wholesale cost of electricity is $30/MW-h (3.6 GJ), so the electricity required to make one gram of antimatter at 50% efficiency (the hypothetical maximum efficiency) would cost $750,000. At TL9, the efficiency is only 0.00833%, meaning that the electricity cost should actually be around $9 billion per gram (the cost is $25 billion per gram in Ultra-Tech, but I think that the electricity is the majority of the 'materials' for the productive formula). In order to make it as affordable as in Spaceships, you would need to either increase the efficiency by 32X and decrease the cost of electricity by 32x.
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Old 02-23-2018, 04:31 AM   #28
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Default Re: [Spaceships] Antimatter Factory

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Which is not practical. So, why would we have anti-matter plasma torches without anti-matt er production? I guess you build some giant solar powered monster station on Mercury and ship the fuel everywhere? :D
That's essentially what I do in Wives and Sweethearts (TL11 with mild superscience): antimatter factories as close to the star as they can be put and still survive, and freighters that shift the stuff around to where it's needed. Most systems have their own factories.
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Old 02-23-2018, 07:38 AM   #29
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An automated orbital platform orbiting Sol at 0.1 AU would receive around 100 PP per Solar Panel Array, translating to 30 GW per Solar Panel Array for an SM+10 spacecraft. If an SM+10 spacecraft possessed 10 Solar Panel Arrays and 5 Antimatter Production Facilities, it could produce 10 milligrams of antimatter per hour at TL9. Of course, it would also suffer 100x as much radiation from solar storms and would have problems storing that much antimatter. Even with that level of production, the price would not drop quickly because of the enormous maintenance cost (you would likely be capturing only 1% of the antimatter produced, meaning that the remaining 99% is turning the facility to Swiss cheese), which would likely be 1% of the facility cost every eight hours.
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Old 02-23-2018, 11:29 AM   #30
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Default Re: [Spaceships] Antimatter Factory

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If an SM+10 spacecraft possessed 10 Solar Panel Arrays and 5 Antimatter Production Facilities, it could produce 10 milligrams of antimatter per hour at TL9. Of course, it would also suffer 100x as much radiation from solar storms and would have problems storing that much antimatter.
Why would there be any more trouble storing 10mg than 1mg? Or 1g or 100g? Pretty sure you just need a magnetic bottle.
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Even with that level of production, the price would not drop quickly because of the enormous maintenance cost (you would likely be capturing only 1% of the antimatter produced, meaning that the remaining 99% is turning the facility to Swiss cheese)...
Production is the yield of antimatter produced and stored by the factory, by definition. It would be very bad design to build a leaky antimatter factory that releases 99% of its production to its environment. Even a-m that couldn't be captured inside the factory would be directed to absorber shields of some sort.

Maintenance would be a problem for being so close to the Sun, not from containing a-m factories.
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