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Comment Re: Energy in? (Score 1) 101

He said that he thinks it will take a day for the air that was bubbled through the solution, to reach the top and be ejected. Pardon me if I think that it would be more like 10 seconds (~8,000 times less than a day, 360 times less than an hour). Yes, a huge volume of air would need to be processed, but after that we're talking about CO2 in solution, which will be a much smaller volume.

Comment Re:I don't even know what "hyperloop" is any more. (Score 1) 195

Indeed. That's one of the few things that one can say has nothing to do with either the original Hyperloop alpha concept or the new college competition entries. Pneumatic tubes mean that they make use of pressure to push things - that's what the word "pneumatic" means. Pressure being the one thing Hyperloop (all permutations) distinctly lacks.

Comment Dated info. (Score 1, Informative) 17

Comment Re:hyperloop without the hyper or loop (Score 1) 195

Uh, the Jetta TDI gets 62mpg in practice (someone did a 5,000+-mile trip going counterclockwise, west across the northern U.S. and then east along the southern U.S), while its gasoline counterpart boasts 32mpg on the highway and 27mpg in the city.

In most of the U.S., you need ULSD. Here on the east coast, gasoline costs $1.55 now and diesel is going for $1.75. A 300 mile tank on my Mazda 3S with the 2.4L (averaging a good 25-28mpg) costs $18 now; a few months back it was still around $25, when gas was $1.92. Surprising me with these low fuel prices.

BTW: At CA electricity and gas prices you're claiming that a 100% efficient Tesla, consuming only 62MJ of electricity, will make that trip, but a gasoline powered car would require 1180MJ to make the same trip. That is a 5% fuel-to-travel efficiency, not the 14-30% [fueleconomy.gov] that is known.

Yes but California is a lunatic state. See also: Texas, where some cities have electricity for under 5 cents per kWh.

Comment Re:Space denial (Score 1) 269

Wouldn't satellites in low earth orbit be protected against that, due to a tiny amount of atmosphere?

Anyhow... 1 ton sand ~= 90 million grains. Low earth orbit speed = 28,000 km/h. Low earth orbit distances = 160-2,000 km, which includes a volume of space of 1.3 trillion km^3. I guess it might be enough to take out a few satellites before they run out of fuel and de-orbit. But I think it would be a small percentage.

[Disclaimer: I am not a rocket scientist]

Comment I don't even know what "hyperloop" is any more. (Score 1) 195

Seriously. I was a big fan of Hyperloop Alpha. But the MIT team that won the "Hyperloop" contest is proposing something nothing like Hyperloop. The test track that SpaceX is building is designed to support a wide range of vehicles, most nothing like that in the Hyperloop Alpha document. So if I say "I like hyperloop", I don't know what exactly it is I'm supporting anymore. What exactly is "Hyperloop" these days?

All I can say is that I really liked the alpha one. The MIT team's maglev thing is Meh^2.

Comment Re:The fun (Score 1) 195

If you're dedicated enough to climb onto a well elevated tube, cut a hole large enough to pour concrete in through inch-thick steel - after sabotaging all of the pressure sensors tbrough the whole length of the tube and feeding them false data - and then using a concrete pump with a very tall boom fill in the tube with concrete, in order to kill people.... then why not just fly planes into skyscrapers like most people? I mean, if you're going to go through that much work.

Comment Re:File a Complaint (Score 1) 86

Try speaking back to them in a drawn Indian accent, and then tell them it sounds like they may have a virus and you'll need to check their Internet History Report. Then start talking about how their computer appears to be distributing large amounts of child pornography, including child bestiality, and that you think they've been receiving bitcoins from a source infected with the Win32-dot-Zika computer virus.

Comment Re:hyperloop without the hyper or loop (Score 5, Insightful) 195

A ground-level, rail-mounted tube doesn't expend energy holding itself against gravity, and faces less wind resistance than an airplane in orbit. That means operating the hyperloop would require less total energy expenditure than operating an air plane.

The Tesla car has higher instantaneous torque and a flat torque curve. The cost for me to drive 300 miles on gasoline is around $25 now; on biofuel, it's around $35; on diesel, it's around $12; on electricity, it's $3. Battery storage loses less energy in conversion than biofuel chemical storage. Electric cars are less complex and require less maintenance than reciprocating piston engines. Superior power, performance, durability, longevity, and cost doesn't seem inferior.

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