Over billions of years, solar wind has deposited an isotope
called Helium 3 onto the lunar surface. Helium 3 is not found in nature on the
Earth, though trace amounts have been produced in nuclear experiments. Helium
3, however, may be the fuel which powers the future, when fusion power become
practicable
While the promise of fusion energy remains elusive, it has
the potential of unlocking a source of power that could sustain civilization
for thousands of years. One problem is that some forms of fusion, using
deuterium and tritium (isotopes of hydrogen) release eighty percent of its energy
in the form of radioactive neutrons, greatly increasing cost and safety issues
for any potential commercial application.
Fusion using helium 3, on the other hand, produces little or
no radioactive byproducts. The closest place where helium 3 can be found in any
quantity is the surface of the Moon, where it is estimated a million tons of
the isotope exists, depositing over billions of years by solar wind. Helium 3
could be mined from the Moon and delivered to Earth where just a few tons of
the isotope could supply all the power needs of the United
States for a year, without pollution
Research into technology to not only develop fusion power
plants using helium 3 as fuel, but to also mine helium 3 from the lunar surface
is currently being conducted by the Fusion Technology Institute at the
University of Wisconsin at Madison. At the current pace of research, helium 3
fusion power is still decades away, though scientists suggest that time might
be greatly shortened given more resources and attention.