This isn't a perfect source but Charles Stross includes Lunar He3 mining in his list of scifi-bunk.
Short answer: No. There's better materials to do fusion with.
Now for a biggie: Mining the lunar regolith for Helium-3. This is junk
science on stilts and it just keeps coming back from the dead. It's
also a barrel of past-their-sell-by-date red herrings that keeps being
rolled out by space cadets whenever they're challenged to produce an
economic justification for space colonization. Here's why it's crap
Fusion, the Jenga-pile begins, is the energy source of the future.
(This may or may not be true: I for one hope it is.) However, the
easiest form of reaction you can run in a fusion power reactor is
deuterium/tritium. This tends to release most of its energy in the
form of neutrons, which can ideally be captured and used to breed more
tritium fuel and produce waste heat to drive a turbine generator. The
problem with neutrons is that they're rather penetrating and when they
slow down enough to be captured by an atomic nucleus they transmute
it, often into an unstable isotope. D/T reactors therefore look likely
to suffer from one of the same problems as fission reactors:
neutron-induced structural embrittlement and secondary activation
producing high level radioactive waste.
Aneutronic fusion—which hasn't actually been tested yet in even a
prototype research fusion reactor—offers the possibility of running on
other fuels and producing <1% of its energy output in the shape of
neutrons. Helium-3, an isotope of helium consisting of two protons and
one neutron, can in principle be fused with deuterium instead of the
(radioactive) tritium and produce power with a far lower neutron
output—the energy-bearing product of the reaction is a proton, which
can be contained using magnetic fields. Hence the interest in He3
fusion reaction designs.
The first problem with He3 reactors (after—cough—we don't know how to
build one yet) is that He3 is incredibly rare. It costs on the order
of millions of dollars per kilogram and the global supply is very
restricted; there's certainly not enough of it to power a global
energy economy even at today's levels. But there is some evidence that
He-3 produced in the sun and emitted in the solar wind may be captured
in the Lunar regolith. The plan, per the proponents of lunar
colonization, is therefore to build vast strip mines on the moon to
extract this vanishingly rare moonshine/pixie dust and export it to
Earth to power our 22nd century energy economy. And of course
estimates that we could power our current level of energy use by
processing 4 million tons of lunar regolith per week are music to the
space cadets' ears because, well, it means big engineering and thus
big steely-jawed engineers with slide rules and socket wrenches on
hand to repair the mining machines when they break. Space colony
Except this is moonshine and junk. Firstly, we don't have an
aneutronic fusion reactor, much less a planetary base load capacity
driven by aneutronic fusion reactors in need of fuel. Hell, we don't
even have a working D-T fusion reactor that can produce surplus
energy; ITER isn't due to achieve first plasma until 2020 and won't
begin D-T reaction operations before 2027, and the Wendelstein 7-X,
while promising, is a generation behind (roughly equivalent to where
the Joint European Torus was in the 80's).
But let's jump the gun. Let's assume we do have a working fusion
reactor. Let's even assume we've put in the decades of legwork
required to build a working aneutronic fusion reactor—it's worth
noting that aneutronic reactions have to run about an order of
magnitude hotter than D-T fusion reactors can achieve, and they're
already in the 100 million Kelvin range. But let's play make-believe:
are we then going to see large-scale lunar regolith mining to fuel the
Because it turns out that if you can build an aneutronic reactor,
then, subject to some considerable amount of fine tuning, you can run
it on fuels other than sparkly lunar regolith moonshine and pixie
dust—notably the proton-boron-11 cycle and the proton-lithium-7 cycle.
Both these fuel cycles are aneutronic and run on isotopes that are
readily available here on Earth in sufficient quantities to power our
civilization for some millions of years without trying to build
massive engineering infrastructure on an airless rock. There's even an
aneutronic fusion cycle that relies on proton-nitrogen fusion,
although it produces less energy and is even harder to achieve.
Nitrogen and hydrogen ... nitrogen makes up about 80% of our
atmosphere, and hydrogen makes up about 15% of our hydrosphere, so
we're not running out of either of those fuels any time soon, either.
Upshot: any work of SF that takes "Lunar 3He mining" as an economic
premise is about as plausible as one that assumes combustion powered
by the release of phlogiston.