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 A British company believes it is within five years of achieving
"reactor relevant" fusion, a major landmark in the six decade long
scientific search for the veritable Holy Grail of energy production.
Fusion is how stars produce energy. It occurs when the nuclei of
light atoms, such as hydrogen, are fused together under extreme
pressure and heat.
Tokamak Energy, from Oxfordshire, believes that the third version of
their compact, spherical tokamak reactor will be able to reach
temperatures of 100 million degrees Celsius by 2020. That's seven
times hotter than the center of the sun and the temperature
necessary to achieve fusion. Such a temperature fuses hydrogen atoms
together, releasing energy, which differs from fission reactors that
work by splitting atoms at much lower temperatures.
Such an achievement wouldn't mean a rapid rollout of a global fusion
electricity network, but would be a significant step to achieving
this by 2050, potentially making an enormous contribution both to
world energy supplies and reducing carbon emissions.
 In Paris world leaders are meeting to try to reach an agreed
framework for action aimed at stabilizing atmospheric concentrations
of greenhouse gases (GHGs). Governments hope the summit will end on
December 11 in a deal that will herald a shift from rising
dependence on fossil fuels since the Industrial Revolution to
cleaner energies such as wind or solar power.
Key to Tokamak Energy's success is the spherical shape of its
tokamak - a device using a magnetic field to confine plasma - and
thin high temperature superconductor strips.
"Here what we're developing is building these small tokamaks, like
ST25, and then we've got other devices using key technologies which
are high temperature superconductors and spherical tokamak shapes,"
senior Tokamak engineer Bill Huang told Reuters. "So we've got a
slightly different shape from traditional fusion and this allows us
to get a higher plasma pressure for a given magnetic field. It's a
measure of efficiency called beta, and by using this improved
efficiency it means that the overall size of our device is actually
quite a bit smaller."
Tokamak Energy says its technology would be similar in costs to a
nuclear fission plant, but without any fissile material and with no
risk of meltdown.
The company, a World Economic Forum Technology Pioneer, says its
compact design means fusion could be generated in far smaller
reactors than assumed possible by scientists until recently.
Huang says that its current ST25 reactor has already reached fusion
temperatures in short bursts, but hopes its third reactor, ST40 -
currently being completed - will enable it to produce "reactor
relevant" conditions.
"This (ST25) will allow us to get very high temperatures for a short
amount of time but what we're looking to do is generate these high
temperatures which are reactor relevant, so we've set ourselves a
100 million degree challenge, and we're aiming to get 100 million
degrees in that (ST40) device," said Huang.
The company is three stages into its five stage process - each
involving a new reactor.
 Tokamak CEO David Kingham believes it will be possible for his team
to transfer energy to the grid by 2030.
"We want to get within five years to an energy gain, and from there
we want to go on in ten years to get to first electricity, a device
where we can demonstrate production of electricity from fusion, but
it may be 15 years before we get energy to the grid in significant
quantities," said Kingham.
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He added: "Fusion is one of those technologies which, if it could be
harnessed, could be scaled up rapidly to be deployed world-wide by
2050 and could make a very big difference to carbon emissions and
therefore to climate change from 2050 onwards."
Tokamak Energy has developed its own magnets using novel high
temperature superconductors and believes that this new material
could be used to construct even more powerful magnets to keep the
hot plasma in position inside a power generating tokamak, at the
fusion reactor's heart.
The ongoing failure of the multi-billion dollar International
Thermonuclear Experimental Reactor (ITER) project in France has
encouraged many small companies to take advantages of advances in
various technologies to attempt to make fusion themselves.
A number of high-profile investors, such as Microsoft's Paul Allen
and Amazon's Jeff Bezos, are backing various small-scale fusion
projects. Investors are attracted to the sheer scale of eventual
return on offer in an era when the world is turning its back on
dwindling fossil fuel stocks and looking for cleaner energy sources.
The fact that many different routes could be developed to achieve
fusion, as opposed to a 'winner-takes-all' race where only one
invention succeeds, is also attractive.
One of the company's largest investors - and the first to stump up
funds - is the Rainbow Seed Fund, co-managed by Mark White. "I think
this opportunity here is possibly one of the most spectacular
combinations of risk and reward that I've ever seen. There are
undoubtedly many challenges still remaining," he said.
Such challenges include making exceptionally strong magnets from
high temperature superconductors.
White says that Tokamak Energy's superconducting magnet inventions
will also help investors like him achieve a good return on their
money. Additional factors make the venture attractive.
"First of all they (fusion reactors) can be constructed in a
factory, so you're talking about economies of scale; and the second
key thing is the way in which the grid itself, the future grid, is
likely to be more dispersed than current central power generation
units, one to two gigawatts per power station. The devices we're
talking about here are likely to be in the order of 100 megawatts,
considerably smaller than those units, and that puts them into the
sort of power output bracket that becomes really very interesting
for large mobile uses, such as some that you might see in the
defense sector - aircraft carriers, submarines, for example."
Other companies in the hunt for a fusion breakthrough include
Dynomak, developed by researchers at the University of Washington in
Seattle, which has proven that their concept works. The next step is
to scale it up so they can achieve the temperatures needed to start
and sustain a fusion reaction.
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