Philip Metzger has a study of mining water on the moon. If water is mined on the moon then it could save satellite missions to geosynchronous orbits about $100 million.
Currently it costs over $100 million for the extra stage to move from low earth orbit or the use of ion thrusters that take one year to move the satellite. The delayed operation is close to the cost of the boost stage.
Water can be mined on the Moon, delivered to a gas station, sold to operators of the space tug, who will then boost the satellite to its final orbit for much less than $100 million per spacecraft.
A wide range of potential customers for the hydrogen and oxygen products has been identified. They can be used to fuel reusable landers going back and forth between the lunar surface and lunar orbit. They can make travel to Mars less expensive if the interplanetary vehicle can be refueled in cislunar space prior to departure. Operations closer to Earth can also benefit from this new, inexpensive source of propellant. Refueling in Low Earth Orbit can greatly improve the size, type, and cost of missions to Geosynchronous Earth Orbit and beyond. This study has identified a near-term annual demand of 450 metric tons of lunar-derived propellant equating to 2,450 metric tons of processed lunar water generating $2.4 billion of revenue annually.
It has been discovered that instead of excavating, hauling, and processing, lightweight tents and/or heating augers can be used to extract the water resource directly out of the regolith in place. Water will be extracted from the regolith by sublimation—heating ice to convert it into water vapor without going through the liquid phase. This water vapor can then be collected on a cold surface for transport to a processing plant where electrolysis will decompose the water into its constituent parts (hydrogen and oxygen).
To achieve production demand with this method, 2.8 megawatts of power is required (2 megawatts electrical and 0.8 megawatts thermal). The majority of the electrical power will be needed in the processing plant, where water is broken down into hydrogen and oxygen. This substantial amount of power can come from solar panels, sunlight reflected directly to the extraction site, or nuclear power. Because the bottoms of the polar craters are permanently shadowed, captured solar energy must be transported from locations of sunlight (crater rim) via power beaming or power cables. Unlike solar power sources, nuclear reactors can operate at any location; however, they generate heat that must be utilized or rejected that may be simplified if located in the cold, permanently shadowed craters.
The equipment needed for this lunar propellant operation will be built from existing technologies that have been modified for the specific needs on the Moon. Surprisingly little new science is required to build this plant. Extensive testing on Earth will precede deployment to the Moon, to ensure that the robotics, extraction, chemical processing and storage all work together efficiently. The contributors to this study are those who are currently developing or have already developed the equipment required to enable this capability. From a technological perspective, a lunar propellant production plant is highly feasible.
The initial investment for this operation has been estimated at $4 billion, about the cost of a luxury hotel in Las Vegas. With this investment however, a scalable market can be accessed. As refueling decreases in-space transportation costs, entirely new business and exploration opportunities will emerge with potential to vastly benefit the economies of Earth. Even with the early customers identified within this study, it has been determined that this could be a profitable investment with excellent growth opportunities.