Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Elon Musk to publish hyperloop design by August

twitter.com

Post reply on HN
Print view View original

161–170 of 175 posts

Re: Elon Musk to publish hyperloop design by August

#161

Post by aetherson »

tocomment wrote: post #141
zefhous wrote: post #109

Here's a description of the closest guess Elon has seen so far. https://twitter.com/John_Gardi/status/356798172842049536

Neat idea but I just don't see how it's cheaper than a high speed rail project?

I agree -- I don't think that any kind of tunnel or tube approach can be done more cheaply than HSR. And I venture to predict that if it is a tunnel or tube concept, it won't succeed in linking LA and SF.

That said, if we take Musk at something close to face value, it has a major advantage that the HSR doesn't: it would be faster than the air route. That would give it at least a fighting chance to draw extremely high ridership and make up for high costs with high revenue.

And if the idea is basically sound, but the implementation is impractical on the SF-LA corridor, then it could be put into use in some other intercity connection with more favorable terrain and lower land costs.

Re: Elon Musk to publish hyperloop design by August

#162

Post by patrickk »

mncolinlee wrote: post #70
btilly wrote: post #53

Earlier quoted context omitted.

Everyone has criticized you based on how great SpaceX is. I'll go the other way. Tesla at its heart is "put a ton of batteries which were developed by other companies into an electric motor that drives a car." People have been trying this formula for over a century. Tesla happened to do it when battery technology was just good enough to work, with really good styling.

Looking at the spectacular flop of the Fisker, packaging is far too often understated. Most people don't understand how complicated automotive systems are and how difficult it is to integrate them all together without numerous bugs and annoyances. Most big name automakers use off the shelf systems from third parties. Tesla did not. Tesla won the highest score ever achieved from Consumer Reports while Fisker perished…

Indeed. Their factory alone is a marvel, not to mention the Model S itself. Check it out on Megafactories, some great details on how they attain very high levels of quality for every vehicle that rolls out the door:

http://www.youtube.com/watch?v=D0GtKfOPZRg

Re: Elon Musk to publish hyperloop design by August

#163

Post by schiffern »

zefhous wrote: post #109

Here's a description of the closest guess Elon has seen so far. https://twitter.com/John_Gardi/status/356798172842049536

"Closest", so we know that's not the whole story.

It looks a lot like a schematic Lofstrom (launch) loop. Just replace the rotor with air.

Re: Elon Musk to publish hyperloop design by August

#164

Post by Someone »

Someone wrote: post #143
nicktelford wrote: post #133

Earlier quoted context omitted.

Enclosed tunnel: "air column" is a give-away. This is essentially a vac-train, except instead of a vacuum, the air in the tube is propelled along with the pod. There will be friction, but only between the air and the inside of the tube. I imagine there'll need to be some kind of "repeaters" to counter-act energy loss, but with so little loss, they could probably be solar-powered; which I think Elon alluded to.

Only between the air and the inside of the tube? Instead of a 100m train with air flowing around it, you get air at length of the track moving along the inside of the tube at the same speed. I know as good as nothing of aerodynamics, but even if you get the latter flow perfectly laminar, I doubt it is a net win, as the contact area is 1000 times as large or so. But educate me. Also, when you move cars into and out of…

Reply to self: we already have been building tunnels through which we move air at high speed. Looking at https://en.wikipedia.org/wiki/Supersonic_wind_tunnel#Power_r..., I read:

"The power required to run a supersonic wind tunnel is enormous, of the order of 50 MW per square meter of test section cross-sectional area."

A train would be, say, 20 square meters in cross section. That would be a GW of power to operate this. And that likely is a severe underestimate. I am sure one cannot lengthen a wind tunnel to kilometers without lots of power loss, but for now, let's ignore that.

For reference: Looking at https://en.wikipedia.org/wiki/TGV#Rolling_stock, a TGV uses at most 12MW at the relatively low speed of 300 km/h. Also, the three Gorges dam produces 22GW (http://en.wikipedia.org/wiki/List_of_largest_power_stations_...)

Re: Elon Musk to publish hyperloop design by August

#165

Post by tokipin »

drgath wrote: post #92
papercrane wrote: post #41

Earlier quoted context omitted.

I was just thinking, it's probably true that most people who try interesting off the wall projects don't become incredibly wealthy.

As Musk has stated, he was one more failed SpaceX launch from pretty much being bankrupt. As a "mad scientist", it's pretty easy to blow your money on ideas that don't quite pan out.

which, on something of a tangent, is why i think government has a critical role to play

Re: Elon Musk to publish hyperloop design by August

#166

Post by r00fus »

dntrkv wrote: post #103
btilly wrote: post #53

Earlier quoted context omitted.

Everyone has criticized you based on how great SpaceX is. I'll go the other way. Tesla at its heart is "put a ton of batteries which were developed by other companies into an electric motor that drives a car." People have been trying this formula for over a century. Tesla happened to do it when battery technology was just good enough to work, with really good styling.

Before the Model S, purchasing an electric car would mean that you are sacrificing performance, luxury, styling, and range for a clean, efficient, electric car. With the Model S, the only sacrifice you make is the range. Everything else is on par, or better, than other vehicles in it's class. People aren't only buying it because it's electric, they're buying it because it's a great car.

Of course, the range issue is only due to an already existing fuel-distribution network in place built over decades.

It could well be that Tesla's goal would be to disrupt that fuel-distribution network, first by selling great client devices (i.e., cars) and then implementing and selling access to the network that provides current petroleum cars with "near-infinite range"

Wouldn't that be living up to your image/name?

Re: Elon Musk to publish hyperloop design by August

#167

Post by InclinedPlane »

tocomment wrote: post #99

Is anyone still thinking it might be a launch loop?

A launch loop doesn't make sense, it's too risky (from a business sense) for this sort of project and too expensive too.

Also, the obvious use of a launch loop is for launch, of course. Why serve a market where prices are cents per kilogram when you can serve a market where prices are hundreds of dollars per kilo? And with less capital investment too.

Re: Elon Musk to publish hyperloop design by August

#168

Post by Turing_Machine »

schiffern wrote: post #119
tocomment wrote: post #99

Is anyone still thinking it might be a launch loop?

I'm in, given that it's the only way to beat the insane right-of-way costs for a transport system in California with a ~20 km turning radius.

I don't know about California in specific, but in the United States as a whole there is plenty of existing and unused/lightly used railroad right of way. Cut a deal with the railroads (most of whom are very, very hungry for cash/investment) and you've got transcontinental capability without needing any eminent domain proceedings or similar obstacles.

Re: Elon Musk to publish hyperloop design by August

#169

Post by schiffern »

Someone wrote: post #164
Someone wrote: post #143

Earlier quoted context omitted.

Only between the air and the inside of the tube? Instead of a 100m train with air flowing around it, you get air at length of the track moving along the inside of the tube at the same speed. I know as good as nothing of aerodynamics, but even if you get the latter flow perfectly laminar, I doubt it is a net win, as the contact area is 1000 times as large or so. But educate me. Also, when you move cars into and out of…

Reply to self: we already have been building tunnels through which we move air at high speed. Looking at https://en.wikipedia.org/wiki/Supersonic_wind_tunnel#Power_r... , I read: "The power required to run a supersonic wind tunnel is enormous, of the order of 50 MW per square meter of test section cross-sectional area." A train would be, say, 20 square meters in cross section. That would be a GW of power to operate t…

I think that's just the power required to accelerate the air. A wind tunnel is a once-through system, not a loop.

Re: Elon Musk to publish hyperloop design by August

#170

Post by moomin »

wissler wrote: post #160
moomin wrote: post #132

Earlier quoted context omitted.

Yes, although I feel the need to point out Jobs wasn't the genius behind Apple in the early years, it was Wozniak. Different time, different man.

I think Jobs is definitely a creative type, he had a clear and distinct vision that went beyond what most CEO's would ever dream of let alone approve to drive resources into. Being a creative type does not necessarily mean being an engineer.

Absolutely, but his vision (the Lisa) was the wrong vision at the time. He refined his vision at next (taking in a lot of other people's good ideas along the way) and returned to Apple at just the right time: when the average consumer was ready to pay a bit more for a refined product.
Post reply on HN