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Comment Re: Forget that (Score 1) 53

Everyone compromised speed for security without realizing it if they went for an out of order processor.

Intel did it much worse than AMD, and about the same as IBM in terms of vulnerability and performance impact of mitigation.

Core 2 was pretty decent, that's fair. But by the time the i7 came around AMD was kicking their ass at everything but single thread. Even though I am a gamer that's never been the only thing I cared about, and I've also always been cheap, so to have AMD provide dramatically more ops per buck and have very competitive processors which were outright faster in many situations has had me an AMD customer solidly since Athlon. AMD never was able to keep up with Intel's process technology, but by the time that ceased to be a thing, all Intel had left was inertia and skullduggery.

My last non-netbook Intel-based system that I bought with my own money (I had an Elitebook with a Core 2 Duo for a moment) was a P2 400 because AMD has kicked Intel right in the goodies in the market segments I care about since right around then. Only Hammer has even been slightly disappointing since Athlon, and it was still an absolute value for money champ.

Comment Re:Erm... (Score 1) 158

t takes between 150 kWh and 800 kWh to separate and liquify a ton of oxygen, so if you're paying $0.10 per kWh, LOX costs $15-80 per ton

It occurs to me that this is a good use of massive solar plants. It wouldn't cost much to idle your oxygen-separation equipment when the sun isn't shining, so you wouldn't need much in the way of battery storage. Grid scale solar without battery backup in a sunny area (like south Texas) can cost as little as $0.03/kWh, which would give you a separation cost of $4.5 to $24 per ton of LOX. Obviously, if you were producing LOX at a scale needed to fuel a fleet of Starships, you'd work to get that towards the bottom of the scale -- so the LOX loadout for a ship could cost on the order of 3500 * 4.5 = $15,750. To launch 150 tons to orbit. Of course you still need methane.

Could you make "green" methane (i.e. without using fossil fuels) with a big solar farm, and what would that cost? You'd do it with the Sabatier reaction to combine CO2 and H2 to get CH4. To make a ton of CH4 you need 2.75 tons of CO2 and 0.5 tons of H2 (stochiometry, dawg). To get a ton of CO2 with direct air capture takes about 2000 kWh of electricity, so 5500 kWh for the CO2. At $0.03/kWh that's $165 for the CO2. However, producing the half-ton of H2 with electrolysis would take 25,000 kWh, so $750. This puts the raw materials cost of green CH4 at around $915. The Sabatier reaction would add a little more, call it $930 in all.

So... Starship could be entirely solar-powered at a cost of around 3500 * 4.5 + 1000 * 930 = ~$946k, assuming $.03/kWh, ignoring equipment and storage overhead. It turns out that the cost is utterly dominated by the cost of methane production; LOX is all but free. But the cost of solar will likely continue to go down so... fuel costs could indeed get really, really low, even with a zero-carbon strategy. Perhaps as low as $2/kg to LEO.

Comment Re:I expect Google to figure this out. (Score 0) 31

I'm not going to claim solar is cheap as I see little evidence of that being the case.

That's because you have no actual evidence with anything. People who have built solar power systems know that it is.

What I do see is solar power subsidies driving spot electricity rates so low they go negative at times

You were so close to getting it.

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