On Wed, 19 Feb 2003 09:56:45 +0000, Ian Woollard <[EMAIL PROTECTED]> wrote:
>>That puts launch >>costs between $25/lb and $100/lb to LEO. Anyone think that's >>feasible? >> >Laser launch can probably do that. A BOTE: Kinetic energy in LEO is about 30 MJ/kg, a kW-hr costs about 18 cents, and a kW-hr is 3.6 MJ. So electricity, the cheapest form of energy (and least storable, what a coincidence) costs about 5 cents/MJ. That puts LEO kinetic energy cost at $1.50/kg, or about 68 cents/lb. The question is, how efficiently can you convert electricity into kinetic energy with a laser and a launch vehicle. If your system efficiency can reach 1%, which I doubt (laser efficiency * propagation efficiency * propellant coupling efficiency * vehicle coupling efficiency), you can make orbit for $68.00/lb. If your system efficiency is 0.1% - more believable - it'll cost $680/lb. That assumes a mass fraction of 0%, of course. A mass fraction of 90% - more believable, though optimistic IMVHO (I don't have a good handle on propellant Isp for laser launch) - drives your cost to between $680/lb and $6800/lb. Then you have the cost of developing a laser powerful enough to launch something - again, I don't know how to calculate the power requirement - and the non-trivial problem of steering the beam quickly enough to steer the vehicle when it gets a few hundred km downrange. Laser launch is initially going to expensive per pound, possibly more expensive than current launch vehicles. That won't matter to the customer, who will care more about the cost per launch, which - because laser launch can handle very small payloads - should be quite competitive. >> If so, I want to buy stock in your unobtainium mine. > >Really? An investor? Excellent! We're not publicly traded though, for >obvious reasons ;-) That's OK. I'll buy your unobtainable shares with my unobtainable money. ;-) -R -- Every complex, difficult problem has a simple, easy solution - which is wrong. [EMAIL PROTECTED] _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
