Solar-pumped laser power transmission, a way to dramatically decrease launch costs?
in [Physics]
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From: William Mook on 7 Mar 2010 16:26 So, a 12 ton satellite costing $300 million to put into orbit is reduced to $440,000 using a reusable laser launch vehicle - because the system weight is dramatically reduced, not just the propellant weight.
From: William Mook on 7 Mar 2010 16:44 On Mar 7, 4:26 pm, William Mook <mokmedi...(a)gmail.com> wrote: > So, a 12 ton satellite costing $300 million to put into orbit is > reduced to $440,000 using a reusable laser launch vehicle - because > the system weight is dramatically reduced, not just the propellant > weight. The other advantage is improved performance at higher speeds. A powerful laser beaming energy to a light sail provides substantial thrust throughout a flight in space, achieving very high speeds, short flight cycles, and long ranges. Going to Mars in a matter of days or weeks requires a far less expensive flight system than going to Mars in a matter of years. Each person requires about a ton of consumables a year. So, a 60 tonne payload and a 3 year flight cycle to Mars delivers no more than 20 people, and more likely 8 to 10 people. Using hypergolics such a system would require something like 1,200 tonnes on LEO, which requires 20 flights - which is what vonBraun spoke of back in the 40s and 50s with his Operation Mars. For redundancy in such a long flight its best to send a whole fleet - of 10 to 12 vehicles which mean we've got 200 to 240 flights to support the mission and 80 to 120 people in the fleet. At $20 million per ton this is a $50 billion to $100 billion program. Which is what we've been talking about since the 40s. Compare this to a 60 tonne payload and a 3 week flight cycle - this is 1/50th the time of the minimum energy mission. So, 1/50th the consumables - and so - 50x the people. 1,000 people max - more likely 400 to 600 people per vehicle. With such a short flight, a single vehicle is perfectly safe and sound. The same laser system that lifts the laser rocket off the ground also sends the laser light sail flying across the solar system. At $20,000 per ton this is a $1.2 million flight cost - costing $2,000 per passenger!!! Its not the propellant costs that are killing us here - its the total system cost due to system size - due to propellant performance.
From: William Mook on 7 Mar 2010 17:01 250 flights requiring 250 expendable launchers to support a dozen interplanetary craft, which requires a space station on orbit put up with another 250 launches with 250 flights - costing $210 billion+ - to put 80 people into the vicinity of Mars and 20 people on the surface - on a 3 year mission - is an exciting and difficult project spanning a decade or more. It would be exciting and inspiring and uplifting. Yet its practical impact would be questioned still. This is the typical mission to mars with hypergolics. Now consider laser propulsion on the same scale. Imagine 1000 reusable launchers costing 1/7th that of the hypergolic launchers so cost $60 billion. These each fly to mars using laser light sails after a laser lauch, and return in 3 weeks. Each vehicle carries 600 people. Each passenger incurs a cost of $2,000. Each vehicle used 12x per year and has a 40 year life cycle. 1,000 vehicles costing $60 billion plus another $40 billion for laser infrastructure - cost 1/2 the 'footprint' mission with hypergolics. This fleet of 1,000 reusable vehicles execute 12,000 flights per year. So, a flight leaves every 43 minutes from somewhere on Earth. 1,000 vehicles operating out of eight space ports around the world, would have 3 outbound flights per day, and 3 inbound flights per day. In a year 7.2 million people would visit Mars and if each paid $5,000 the operate generates $36 billion each year on the $100 billion invested. Would 7.2 million people each year pay $5,000 and 3 weeks to visit Mars? Well, there are 200x as many air passengers each year. So, we're talking about a very select clientele, despite the volume. This would be even more inspiring and uplifting, and transform life on Earth, and our relationship to our frontier. So, its not just about propellant cost - its about system cost and system performance achievable for the dollars we're spending and what we're getting back for those dollars in terms of a changed world.
From: Brad Guth on 7 Mar 2010 18:22 On Mar 7, 2:01 pm, William Mook <mokmedi...(a)gmail.com> wrote: > 250 flights requiring 250 expendable launchers to support a dozen > interplanetary craft, which requires a space station on orbit put up > with another 250 launches with 250 flights - costing $210 billion+ - > to put 80 people into the vicinity of Mars and 20 people on the > surface - on a 3 year mission - is an exciting and difficult project > spanning a decade or more. > > It would be exciting and inspiring and uplifting. Yet its practical > impact would be questioned still. > > This is the typical mission to mars with hypergolics. > > Now consider laser propulsion on the same scale. > > Imagine 1000 reusable launchers costing 1/7th that of the hypergolic > launchers so cost $60 billion. These each fly to mars using laser > light sails after a laser lauch, and return in 3 weeks. Each vehicle > carries 600 people. Each passenger incurs a cost of $2,000. Each > vehicle used 12x per year and has a 40 year life cycle. 1,000 > vehicles costing $60 billion plus another $40 billion for laser > infrastructure - cost 1/2 the 'footprint' mission with hypergolics. > This fleet of 1,000 reusable vehicles execute 12,000 flights per > year. So, a flight leaves every 43 minutes from somewhere on Earth. > 1,000 vehicles operating out of eight space ports around the world, > would have 3 outbound flights per day, and 3 inbound flights per day. > In a year 7.2 million people would visit Mars and if each paid $5,000 > the operate generates $36 billion each year on the $100 billion > invested. > > Would 7.2 million people each year pay $5,000 and 3 weeks to visit > Mars? Well, there are 200x as many air passengers each year. So, > we're talking about a very select clientele, despite the volume. > > This would be even more inspiring and uplifting, and transform life on > Earth, and our relationship to our frontier. > > So, its not just about propellant cost - its about system cost and > system performance achievable for the dollars we're spending and what > we're getting back for those dollars in terms of a changed world. There's no question that you should be in charge and running 100% of everything yourself. Problem is, there's not enough Einstein clones to provide the necessary labor force that everything of Mook requires, so we'll have to import the smart ones from another planet. So, perhaps the first thing is to get the rest of us village idiots up and running with a spare/surplus terawatt of clean Mook energy, plus loads of liquid hydrocarbons from all of our otherwise nasty coal, and the cheaper that energy the better. ~ BG
From: Brad Guth on 8 Mar 2010 00:04
On Mar 7, 5:16 pm, Fred J. McCall <fjmcc...(a)gmail.com> wrote: > I think you get some idea of how 'good' Mookie's numbers are by the > simple fact that he claims that SSTO is 'NOT POSSIBLE' with > conventional propellant types. There's lots of data out there from > people who are actually knowledgeable in the field (unlike Mookie) > that says otherwise. > > For example: http://www.dunnspace.com/alternate_ssto_propellants.htm > > Or perhaps:http://www.reactionengines.co.uk/downloads/JBIS_v56_108-117.pdf > > Mookie thinks that an ability to do arithmetic is sufficient to > 'prove' things. It's not. Mook pretty much hates anything that's not his idea to begin with, such as the following. H2O2/propargyl alcohol * about 40 % more payload than RP-1 ~ BG |