Hi All

Fascinating. Seems pretty clear that there are some really idiotic fixed costs imposed by regulations that strangle "Cheap Access To Space" efforts before they even launch. How insane, but makes sense if the Gov't has been lobbied to protect the status quo. Flags-and-footprints is all we'll ever get out of the Human Space Exploration Initiative if the Fed doesn't get serious about opening up space for all.

OTOH I really would like to see a serious business plan for CATS that showed how money could be made by increasing payload lofted to Space. Cheap access needs BIG payloads or it just won't happen. Bigelow's space hotel is part way there, but dozens of them are needed not just one.

Or something else that needs lots of payload lofted to LEO and beyond. Ok... you know where I'm going, but have a read of this research piece by Geoffrey Landis on new concepts for Solar Satellite Power. SSPs are a ready market for large haul to space - if they can be made sound economic propositions. Landis' designs go a long way towards that goal by targeting specific parts of the energy market - peak-power during daylight hours - and simplifying the SSP to suit. A factor 8 cost reduction results by using gravity anchored configurations that allow intergrated power collection and transmission units, thus avoiding the immense amount of cabling that a gigawatt SSP otherwise requires. Also making the system not track the Sun means eliminating a massive power-transfer slip-ring between the array and rectenna.

Clever designs mean lower mass-to-orbit. Another concept uses L'Garde style inflatables as both power collectors and microwave array - by orbitting at the L2 halo this means the array can both collect and beam power while pointing Sun/Earthwards. Depending on microwave attenuation an array massing 1300 tons can generate 1 to 2 gigawatts. To get it to L2 I'd advocate using a predeployed collector unit and an electric propulsion system. Individual units produce ~ 100 kWe power enough for a near-term ion-drive able to haul multiple power-units. And by the array being so many independent power/transmission units it degrades gracefully rather than catastrophically if a segment is damaged.

The only problem with the L2 system is that it sends power to Earth's night-side, thus getting off-peak prices for its power. But as we switch from fossil fuel vehicles to fuell-cell/electrical then off-peak demand will grow.

Adam