/sci/ - Science & Math

How viable do you think space based solar power stations could be?

Continuing the discussion about Helicon Dual Layer Thrusters, the fact that you get ~1mo Mars manned ferry class thrust levels out of 50MWe input even hauling a fusion reactor along is really cool, because that means if it's for fixed routes between Earth and Mars, it might be possible to have one ferry route without using nuclear power at all. Assuming we can leave the entire mass of the reactor at home, we can probably get away with 20% of the electric power and propellant flow to get the same delta-V, so we'll use 10MWe as our target value for the engine input.

Assuming that the math checks out at Atomic Rockets[1], usually a safe bet, we have a rough beam efficiency factor for converting laser received input to electrical output of 0.63. That means to make our 50MWe HDLT-rod go, we need 10/0.63 = 16MW of laser hitting its receiver dish. During the standard launch window the loss from Earth to Mars is less than 50%, so we can call the source beam power 32MWe.

Assuming solar panels that are 15% efficient, and a laser array that is 50% efficient at turning electricity into light, and 1367 W/m^2 light at 1AU, that means we could build a solar powersat of 312,119 m^2... less than 0.4km^2, and without the political problems of a nuclear reactor in orbit. Then you can have slowboat Starships haul about 1km^2 of solar panels (to account for weaker solar flux at Mars orbit) and a laser emitter to Phobos or Deimos for providing the boost for the trip home.

[1]: www.projectrho.com/public_html/rocket/infrastructure.php#id--Solar_Power_Stations--Beamed_Power

>On a side note, can you guys take the political discussion to >>>/pol/ ? I just want to talk about rockets. I have /pol/ open in another tab to talk about Trump stuff there.