Nuclear power without radioactive waste? The lunar helium-3 perspective

摘要

~3He mining on the Moon has recently received much interest and was proposed as an incentive for lunar exploration, with ~3He as the perfect fuel for nuclear fusion energy without radioactive waste. The Earth has no significant ~3He resource. However, the lunar regolith, the upper few meters of loose material on the Moon, appears to contain about 20 ppb of ~3He implemented by solar wind over billions of years. The value of ~3He can be estimated at around 1 million US dollars/kg, based on energy content and comparison with nuclear fission reactors and zero-emission coal plants. The corresponding ore value then is 20 US dollars/t. Both grade and value-per-tonnage data are comparable to marginal diamond mining on Earth, but the specific economics of Moon mining will greatly depend on a drastic reduction of the currently prohibitive transport costs, as well as on support from other space activities.