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Comment Re:Erm... (Score 1) 157

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:Erm... (Score 2) 157

It will never cost that little. A Falcon 9 has about 400 tons of propellant. If it were all commercial diesel, it would cost $400,000, or $17 per kg of weight launched to LEO. But of course it's not commercial diesel. Liquid oxygen and RP1 are both much more expensive.

Starship burns methane, not RP1.

Between SuperHeavy and Starship, a fully-loaded stack needs 3500 tons of LOX and 1000 tons of CH4. So what do those cost?

Well, oxygen is easy to get from the atmosphere, so the cost of LOX is really just some equipment (which isn't terribly expensive to buy and maintain) plus electricity, and the cost ends up being dominated by the cost of electricity. It 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. There are some other costs to handle and store it, so let's say $100/ton.

CH4 can be created many ways. The cheapest is probably to purify natural gas, which costs about $190 per ton (that site shows ~$5 per 1000 ft^3, and a ton is 38k ft^3). Add some costs for purification and cooling, so call it $250/ton.

3500 tons LOX * $100/ton + 1000 tons CH4 * 250/ton = $600k. Musk usually calls it $1M, which seems pretty reasonable, since they're probably not separating/purifiying it themselves and there transportation costs. 150 tons of payload to LEO with $1M worth of fuel means the fuel-only cost is $6.67/kg.

Comment Re:Erm... (Score 1) 157

we have enough accumulated knowledge that just getting to orbit shouldn't be accompanied by a string of failures like Starship has been having

Nonsense. Our only experience with reusable orbital rockets is the space shuttle, which was an unsustainably-expensive and complex beast that was more refurbishable than reusable and had a payload one fifth of what Starship is designed for. It's all of the differences that aim to make Starship both reusable and cheap that make it hard. It's possible that it's just too ambitious, that we don't yet have the technology to make a cheap, fully-reusable (not refurbishable, reusable) orbital rocket with massive capacity. No one else has done it... no one else is even trying, that's how hard it is.

Failure is expected. If they managed to launch and land both Starship and SuperHeavy in less than a dozen test flights, that would be the surprise.

Comment Re:Xfce also uses GTK (Score 1) 131

XFce is using GTK3 currently and the change is in GTK5. Hopefully, as more users have the sad realization about Wayland, GTK5 will be end of the line for GTK.

GTK's decision isn't that surprising, they've been part of freedesktop for some time, so they've bought in on the plan to cram Wayland down people's throat with a stick if necessary, much like RedHat in general.

Comment Re:Raise your hand if you're surprised (Score 1) 199

Between all the permafrost melting across Russia to methane to massive fossil fuel use, how can anybody be surprised? I have long viewed the worst possibilities as the most likely. The most likely predictions always seemed pretty damn optimistic. We fucked.

I'm surprised, and you should be too, if your view is evidence-based, because this is a new effect that was not predicted by any of the previous models, which already consider the melting permafrost, methane emissions and fossil fuel use.

Comment Re:Wayland is the IPv6 of display protocols (Score 1) 131

BZZT. That's a dodge and I suspect you damned well know it. LIE LIE LIE. You did successfully repeat the big lie, I'll grant you that.

I am quite sure it was understood that the people complaining were referring to the simple act of forwarding the X server connection to the remote X server (display) either directly or through ssh. I was lied to directly after being quite specific that that was what I was talking about (that would be the calling out). It was even a shade worse than Clinton's "I didn't inhale" (because it was in brownies). Truly a mis-direction worthy of a politician. Also known as a lie.

I remember history quite well.

Comment Re:Wayland is the IPv6 of display protocols (Score 2) 131

In the early days right here on /. and on wayland's project blogs.

The claim was that X11 doesn't support remote display. Then when the foolishness of that claim was loudly called out, it was "Well that isn't REALLY remote support". Then that was called out and the claim was "it'll be implemented any day now..."

That was enlarged that it would be through an external proxy. Then that external proxy would be 3rd party. Then it would be started any day now.

Lie after lie after lie. Not a good look for open software.

Comment Re:Resonate with customers (Score 1) 79

This was a pre-emissions model (the car wasn't new when I got it). The only pollution control I remember it having was a PCV valve. After adjusting net vs gross HP, the 5.7L engine was rated for similar power as my current (non turbo) 2.5L. It also probably burned through 2.5X the fuel, and produced orders of magnitude more smog.

The new car is probably heavier, but I assume that a wider power band and more efficient transmission give my current car the overall edge in performance specs. The old car probably had better bottom-end torque, so it could do burnouts easier. That, along with the loud noise, rattling chassis and very scary handling characteristics probably made it feel faster than the current car, but that's nothing but psychology.

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