This is the ultimate SOLAR EAGLE version..tailerons, ground effect and 2800 m2 of solar panels !
The rocket first stage is reusable and second is for a long journey to Mars ( or even Jupiter perhaps ) and the ION thruster for the return journey. The lander worx a bit differently as a combo than the Apollo did. Downsizing and new materials play a role and the possibility to fly to space in mild temperatures via solar energy to 50 km altitude.
The indicated 1860 hp is from solar alone. In addition the plane could carry a 3600 kw power worth of accus to be used at the high to gain super sonic speeds in the really thin air ( in order to stay airborne ).
The Vincent Burnelli idea of a lifting body has been implemeted fully in this as well.