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Some interesting technical background
here:
Not mentioned: while He3 may be *relatively* more
abundant on the lunar surface, there's no question that we're talking about very
low grade helium ore, and therefore very high investment in extraction.
Sending raw lunar soil back is a non-starter. Even if only extracted
helium were returned to Earth, there would be an issue of ROI. Extracted
He3 returned -- now, you're talking. But even if that's a guaranteed ROI,
the question mark follows the 'I'. To keep the investment manageable, we
still need to address the bottleneck of Earth-to-orbit costs.
Schemes like Space Elevator and momentum-transfer tethers offer potential for
reducing costs by two orders of magnitude, but even there, you're looking at a
staggering upfront investment just to bootstrap the bootstrap.
I believe there are solutions, but they will be very
long range, very cost-conscious, about as sexy as sea tortoise, and not much
faster. Am I alone in biting my nails about SMART-1's plodding progress
through the van Allen belts on its way to the Moon? This kind of
technology is far more significant than your average space enthusiast realizes,
I think.
-m
----- Original Message -----
Sent: Saturday, November 15, 2003 3:28
AM
Subject: Helium 3 on Luna as an energy
source
By Satyabrata Rai Chowdhuri
With the oil age
starting to appear alarmingly finite, and with governments all over the planet
searching for new energy sources, space scientists are looking at yet another
fuel source, this one distributed on the moon over billions of years as birds
distributed guano on the island of Nauru.
The energy source is Helium
3, which exists in minute quantities on earth but which has been deposited on
the moon by solar winds, a rapid stream of charged particles from the sun,
from the dawn of time. Helium-3, or Astrofuel, as scientists have dubbed it,
sounds, well, almost too good to be true. All they have to do is figure out a
way to go get it, and then to build a plant to transform it to energy once
they get it back here.
Estimates of world energy use and recoverable
reserves vary widely. Average energy consumption, measured in crude oil, is
71,530, barrels per day against a total known world reserve of about 1.0
trillion barrels. Thus a conservative estimate indicates that commercially
viable oil supply could be exhausted in 40 to 50 years although by another
estimate there is enough coal in the United States to last another 275 years
at current consumption rates. Coal, however, is a dirty fuel that is costly to
clean up through filters and scrubbers.
At present rates of
consumption, which are unlikely to hold steady forever as alternative fuels
come on stream, when the population reaches the 10 billion mark consumption is
projected at about 100 to 150 billion barrels of oil per year. Mankind is
already looking for energy sources based on solar, wind, hydro, geothermal and
biomass and certainly some will continue towards playing a major role in
energy production.
Nuclear fusion is the other source of energy, but
faces lots of political problems because of the radioactive waste it produces
and because it produces a great number of neurons, which damage reactors,
cutting their life. On the other hand, a fusion reaction carried through
Helium3 releases only one percent of its energy in the form of neutrons. As a
result, this type of reactor becomes easy and reduces radioactivity to a very
low level, scientists working on the subject say.
Enter Astrofuel, as
Helium-3 or He3 has come to be known, which was discovered on the moon in 1969
when American astronauts first arrived, although the link between the isotope
and lunar resources was not made until 1986. Scientists describe it as the
most efficient known source of power, because 99 percent of the energy can be
released as charged particles and thus be converted into electricity with
greater efficiency. The level of radioactivity is so low that a complete
reactor meltdown would not spread radioactive particles. And the reactor could
be dismantled at the end of its useful life to be disposed of like any other
ordinary median instruments.
The Center for Space Automation and
Robotics at the University of Wisconsin in Madison first conceived the idea of
mining Astrofuel from the Moon in 1986. The center, one of 16 National
Aeronautics and Space Administration (NASA)-funded facilities for the
commercial development of space, is positioned to manage the project because
of the university's already existing fusion, space and life support research
program.
Researchers at Madison say they are certain that He3, an
isotope of helium with one less neutron than helium itself, could replace
fossil fuels. While it is rare on earth, it is available in large quantities
on the moon. One tonne, they say, could supply the energy needs of a city of
10 million people when combined in a fusion reactor with a form of hydrogen
extracted from water. It is hardly difficult to thus imagine the impact that
Astrofuel could have on world energy supplies.
The extremely high
power density means that only 28 tonnes of Astrofuel, approximately the
payload of the current US Space Shuttle, could supply the entire electrical
demand of the US for a year. Even at a selling price of US$1 billion per
tonne, the energy cost would be equivalent to oil at $7 a barrel.
Unfortunately, the space shuttle is not at this time configured to fly to the
moon, and a new space vehicle would have to be developed.
The nation
that develops the technology to retrieve Astrofuel could thus find itself in a
commanding economic and strategy position in this century. The US already has
the research and resource lead for recovery. While some He3 is available on
earth, the quantity is not sufficient to be exploited commercially. The US
strategic reserve amounts to only 29 kg, with another 187 kg mixed up with
natural gas. By contrast, the moon has an estimated reserve of 1.1 billion
tonnes of He3 that has been deposited by the solar wind.
The
commercial viability of Astrofuel was determined by the Wisconsinâs University
Research Center in 1987, a year after its discovery. In 1987 prices, it was
found that the US spends $40 billion annually to buy coal, oil, natural gas
and uranium to produce electricity. For the megawatt volume of electricity for
one year, the US might need to import one spacecraft load of fuel at a cost of
$25 billion - about a fourth of the price of crude today at the aforementioned
$7 per barrel.
Obviously, billions of dollars would be required or
research and development by participating countries and would involve the
development of many technologies that currently remain to be created. Foremost
among them are superconducting magnets, plasma control and diagnostics,
robotically controlled mining equipment, life support facilities, rocket
launch vehicles, telecommunications, power electronics, etc. Though the
investment seems astronomical, compared to the benefit derived, the
justification seems more than adequate.
For one thing, the developed
world would no longer be held hostage to the Middle East, where the
preponderance of the worldâs fossil fuel reserves are located. American
scientists have already declared that the moon could be the Persian Gulf of
the present century. Two liters of He3 would do the work of more than 1,000
tons of coal.
And who would own this real estate? No doubt, the only
affordable source of energy would be completely dominated by American
industries. With the collapse of the USSR, Russiaâs space program has largely
disappeared. The Chinese, who only launched their first man into space last
month, are well behind in the race. India, with its fledgling space program
even less-developed, is even further behind. The Euroland space program is
hardly oriented towards anything beyond launching commercial earth satellites.
It is thus possible that every member of the United Nations could be
forced to stand in a queue to receive a quota of fuel fixed by Uncle Sam. All
discussion about energy security would take a back seat. The UN will discuss
everything, but its members would go on waiting for their quota to arrive.
Astrofuel would decide politics, economics and the world order.
The
technology to harness He3 as an energy source is a continuing process in the
laboratories of the US universities. Miniaturization of He3-driven reactors
would take an immense role in the new world order.
Dr Satyabrata
Rai Chowdhuri is a former professor of international relations at Oxford
College in the UK and a guest professor of international relations at the
London School of Economics & Political Science.
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