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Comment Re:Time to resurrect the old meme... (Score 4, Insightful) 228

Just to add some insight:

Trump, in a Truth Social post, said: “We require a commitment from these Countries that they will neither create a new BRICS Currency, nor back any other Currency to replace the mighty U.S. Dollar or, they will face 100% Tariffs, and should expect to say goodbye to selling into the wonderful U.S. Economy.”

https://ancillary-proxy.atarimworker.io?url=https%3A%2F%2Fapnews.com%2Farticle%2Ftru...

So clueless.

The fact is that the trade imbalance is the largest single factor that makes the US dollar the world currency -- and also helps to keep the federal debt cheap. All of those countries that have a trade surplus with us send us lots of goods and in exchange they get lots of dollars. What do they do with them? They buy US-denominated securities, including treasury bonds. So many people and organizations around the world holding large reserves of US-denominated securities is what makes the dollar the world's default currency.

To the extent that he succeeds at "correcting" the trade imbalance, he'll undermine the dollar's status. And trying to bully countries into sticking with the dollar by threatening action that will make the dollar worth less to them is just... clueless. And that's assuming his actions to explode the debt while escalating financing costs doesn't result in enormous devaluation of the dollar, which would make it worthless rather than just worth less.

On balance I think I'm mostly glad that Trump is a moron, because if he weren't he would be really dangerous. On the other hand, if he had either a brain or the humility to listen to people who do, he might understand that he's trying to destroy what he's trying to control, and that winning that sort of game is losing. Probably not, though. He's amoral enough to be okay with ruling over a relative wasteland, because he and his will be better off.

Comment These CEOs don't understand basic economics (Score 1) 93

The drive to the bottom line (see what I did there?) is a slippery slope. A good CEO will balance profitability with employee satisfaction. Why? Because a company's employees should be their best customers. If you have "half" as many customers right out of the gate, the company is going to do worse as a result. People who talk about AI eliminating jobs forget that their business model relies on a base of customers willing to spend their money on the product. If people are out of work, they aren't going to buy a shiny new car.

Comment Re:Erm... (Score 1) 163

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:Portable hardware (Score 1) 43

The question isn't 'are they number 1' or 'are they number 2' but 'did they sell enough hardware and software, or otherwise benefit from having the brand, to make it worth their while?'

After all, you mention the Wii, but a lot of people who bought a Wii never bought a game past Wii Sports. Many people bought PS3s to be Blu-Ray players, just like many people bought a PS2 to be a DVD player.

Comment Re:Erm... (Score 2) 163

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) 163

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:Excellent (Score 1) 209

Difficult is not equal to impossible. Heat can be used to boil working fluids, which can be used to drive turbines, which can create energy, which can in turn be used to run AI chips, which give off heat, which can then also be harvested to boil working fluids...Not really a perpetual motion machine, but the inefficiency in the system can be used to suck more heat out of the heat pumps anyway. Inefficiency in this case is a feature.

Comment Re:Raise your hand if you're surprised (Score 1) 209

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.

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