Reply to: Apple patents something to do with hydrogen fuel cells

[TimberWolf]

Given the problem, how are you measuring efficiency?

Maximum efficiency is when the total mechanical energy equals the energy used.

Because rockets are so grossly inefficient, rocket travel will always be expensive economically too.

[Doggy Styles]

Rockets will always be inefficient because most of the energy goes into lifting the fuel itself.

Given the problem, how are you measuring efficiency?

[NotAllThere]

Anti-matter factories is what we need.

[TimberWolf]

I understand the physics.

What you don't understand is economics - there is no other feasible way to get stuff into orbit, end of story.

You have new way to do that cheaply with your physics? Great - a lot of companies would love to cut down costs of launching satellites up there, but word of worning - none of then give a flying monkey about physics.

Do you know how much energy it takes for you to walk up the stairs (or take the lift) to get to your executive flat, versus the energy that would be needed if you used a rocket? You say you understand physics so I will enjoy seeing the answer in the morning

I said rockets were inefficient, I didn't say that there is currently any other way of getting to orbit. You like totally invented that argument.

Without the physics there is no economics, unless you want rapidly emptying pockets. Want to invest in a perpetual motion machine?

Work is in progress on more efficient methods of getting things in to orbit, for example by using air breathing engines. And once in space further proposals still, solar sails, nuclear powered engines, etc.

[NickFitz]

Has "obligatory xkcd" become one of those "Godwin's Law" things yet?

[AtW]

You have to understand the physics though

I understand the physics.

What you don't understand is economics - there is no other feasible way to get stuff into orbit, end of story.

You have new way to do that cheaply with your physics? Great - a lot of companies would love to cut down costs of launching satellites up there, but word of worning - none of then give a flying monkey about physics.

[TimberWolf]

Looking at the Wiki, getting to Low Earth Orbit isn't as energy inefficient as I thought:

Given the energy input of 20 TJ, the Space Shuttle is about 16% energy efficient at launching the orbiter and payload just 4% efficiency if the payload alone is considered.[citation needed]
Fuel efficiency in transportation - Wikipedia, the free encyclopedia

Efficiency would be much worse if you needed to land and take off some place though, say to go to the Moon, so perhaps that's where I recollected my numbers ('a fraction of a percent efficient').

[TimberWolf]

When trying to make something big happen physics is nothing, it's all about economics - the cost of launching newer rockets from private companies probably 10 times cheaper than the kind of cost everybody got used to in the last 10 years.

As I said - there is no currently any other proven method of launching commercial grade heavy stuff up in orbit other than rockets.

If you have come up with a better way then stop posting tulip on CUK and get it working!

You have to understand the physics though, to make that first step, and the the next steps. Most big companies and ideas were founded by geeks you might be glad to hear.

Anyway the last guy who was getting somewhere ended up deaded: Gerald Bull - Wikipedia, the free encyclopedia

It was to be capable of placing a 2,000-kilogram projectile into orbit

Not sure how realistic that claim is, bit dubious myself, it would be mighty impressive to get something into orbit ballistically without destroying it and the gun in the process.

But people are working on it. Also sometimes there are large capital costs that deter the short-sighted, see the British Space Programme (RIP).

[AtW]

I was speaking in physical terms.

When trying to make something big happen physics is nothing, it's all about economics - the cost of launching newer rockets from private companies probably 10 times cheaper than the kind of cost everybody got used to in the last 10 years.

As I said - there is no currently any other proven method of launching commercial grade heavy stuff up in orbit other than rockets.

If you have come up with a better way then stop posting tulip on CUK and get it working!

[TimberWolf]

Look, it's like this - rockets it the CHEAPEST available means of putting stuff to orbit right now.

Efficiency talk is pointless unless you've got better way of doing it.

At the moment rockets fired up by NASA cost so much due to Govt higher costs: pensions, extortion from sole suppliers etc, but private smaller companies will cut down price massively.

"CHEAPEST available means of putting stuff to orbit right now" is a strawman you posited only to demolish yourself. At least twice now I never said it wasn't.

I was speaking in physical terms. A tiny fraction of the energy in those huge rockets ends up in an orbiting satellite and sacking people and cutting pensions payment won't change that. Rockets will be inefficient even with smaller companies.

[AtW]

Rockets will always be inefficient because most of the energy goes into lifting the fuel itself.

Look, it's like this - rockets it the CHEAPEST available means of putting stuff to orbit right now.

Efficiency talk is pointless unless you've got better way of doing it.

At the moment rockets fired up by NASA cost so much due to Govt higher costs: pensions, extortion from sole suppliers etc, but private smaller companies will cut down price massively.

[TimberWolf]

As I said none of those are in production - there is NO other more economical way to launch stuff (commercial weights) into orbit but rockets.

Newer rockets made by SpaceX and others should cut down costs nicely as well.

Rockets will always be inefficient because most of the energy goes into lifting the fuel itself.

Funnily enough, the very thing we are talking about, hydrogen, gets in to orbit without any help from us at all.

[AtW]

WAtW said. Don't confuse might for IS.

Mwah!

There is Might and there is Magic.

[bless 'em all]

As I said none of those are in production - there is NO other more economical way to launch stuff (commercial weights) into orbit but rockets.

Newer rockets made by SpaceX and others should cut down costs nicely as well.

WAtW said. Don't confuse might for IS.

Mwah!

[AtW]

People are working on it, e.g.

Reaction Engines Limited :: Press Release 19 Feb 2009
Project Babylon - Wikipedia, the free encyclopedia
Railgun - Wikipedia, the free encyclopedia
Space elevator - Wikipedia, the free encyclopedia
Lightcraft: A Laser Push to Orbit

Chemical rockets (what we are talking about) are out of the question for serious space travel.

As I said none of those are in production - there is NO other more economical way to launch stuff (commercial weights) into orbit but rockets.

Newer rockets made by SpaceX and others should cut down costs nicely as well.