Potential of Lunar Helium-3 Fusion Power

Schmitt, Harrison H.¹ (1) University of Wisconsin-Madison, Albuquerque, NM

The long-term and primary financial, environmental, and national security rationale for a Return to the Moon consists of access to low cost lunar helium-3 fusion power. Helium-3 fusion represents an environmentally benign means of helping to meet an anticipated eight-fold or higher increase in global energy demand by 2050. Titanium-rich regolith over lunar mare basalts have a probable concentration of helium-3 of 20ppb. Two square kilometers of large portions of the lunar surface, to a depth of three meters, therefore contains about 100 kg (220 pounds) of helium-3, i.e., more than enough to power a 1000 megawatt (one gigawatt) fusion power plant for a year. In 2006, helium-3's energy equivalent value relative to $2.50 per million BTU industrial coal equaled about $1400 million a metric tonne. One metric tonne (2200 pounds) of helium-3, fused with deuterium, a heavy isotope of hydrogen, has enough energy to supply a city of 10 million, or one/sixth of the United Kingdom, with a year's worth of electricity or over 10 gigawatts of power for that year. In this context, the economic geology of lunar helium-3 is of significant interest to the formulation of space, energy and international policies.