Launch costs to GEO using solar-powered orbit transfer vehicles

Analysis of Hall-effect thrusters and ion engines for orbit transfer missions

“…Thus, the power mass/propel lant mass term increases with increasing specific impulse, As specific impulse is increased. the increasing power mass/propcllant mass term is countered by the decreasing propellant mass fraction in Equation 3. resulting in the initial rise in payload fraction versus specific impulse that we sec in Figure 8.…”