The major cost driver of any planetary outpost is that of lifting its mass away from Earth. Even future heavy-lift vehicles, such as the proposed Shuttle-derived cargo vehicle shown here, will cost thousands of dollars to get each kilogram of material to the Moon. A major element in the case for Indigenous Space Materials Utilization stems from reducing this logistics train. By producing materials on the planet where an outpost is located, the cost, operations, and launch schedule of Earth-to-orbit vehicles can be reduced.
The use of lunar-derived LOX is thus a high-leverage item because it frees our space vehicles from the inefficient and costly exercise of shipping bulk propellants. The total cargo that must be shipped to the Moon will be reduced significantly. And for the remaining flights, instead of transporting large quantities of LOX to the Moon, more people, complex equipment, and scientific instruments can be shipped to provide additional capabilities at the lunar outpost. This effect can be increased dramatically when we also produce lunar-derived fuels, such as hydrogen or methane.
Perhaps as important as propellant production will be the use of the regolith for the manufacture of basic material. While it is true that much of the cargo arriving on the Moon will be extremely complex equipment, there is a real need for simple, basic infrastructure such as roads, rocket blast protection, and structures for habitats, storage, and equipment repair. If brought from Earth, the mass required for these uses would be enormous. For example, just for protection from solar particle radiation, the amount of mass that would have to be brought to the Moon represents several Space Shuttle launches. Based on present launch costs, the expense of transporting the hundreds of metric tons needed to protect an early habitat from this dangerous radiation would surpass a billion dollars.
Just as important as cost is the high flight rate which would be needed to support this effort. This would strain the capacity of our launch systems. When LOX is produced on the Moon, fewer flights to LEO will be necessary. On-orbit assembly and processing at Space Station Freedom (SSF) can also be reduced. Indeed, the additional facilities that would otherwise be required here on Earth and at SSF represent further cost savings made possible through an ISMU program.