In
1965, Fred Lee, the UK’s then Minister
of Power, famously told the House of Commons that 'we have hit the jackpot this time,' with the Advanced Gas-cooled
Reactor (AGR). That was maybe a reference back to an earlier episode, when
expansive claims were made that the ZETA nuclear fusion test plant heralded a
global breakthrough- it didn’t. Unfortunately,
things also went very wrong as the AGR programme unfolded. The first station, on
the south Kent coast, was Dungeness B. It was ordered in 1965, but did not start up
until 1982, over 17 years later, by which time its cost had reached more than
five times the initial estimate, and its output had been scaled down by over 20%.
In 1985, two decades after the original order, the second reactor at the
station had only just started up. Atomic Power Constructions, the company that
won the Dungeness B contract in 1965, had by 1970 collapsed in total technical,
managerial and financial disarray:
Project
disasters like that might be seen as part of the learning process, though the
UK seems hell bent on a repeat, with EDF’s £24bn Hinkley EPR project, to be
followed perhaps by more, with a variety of new ‘first of kind’ reactors
projects being proposed. As Peter Atherton put it in
evidence to a Lords committee: ‘we will be building
four different reactor types, with at least five different manufacturers,
simultaneously. That is industrial insanity’.
While
some nuclear enthusiasts hope that these Generation III reactors, like the EPR
or its rivals, will be successful, there is also pressure to move on to new
technology and so called Generation IV options, including liquid sodium-cooled
fast neutron breeder reactors, helium-cooled high tempertutre reactors and thorium-fuelled molten salt reactors, at various
scales. As I describe in my new book Nuclear Power: Past, Present and Future,
many of them are in fact old ideas that were looked at in the early days and
mostly abandoned. There were certainly problems with some of these early
experimental reactors, some of them quite dramatic. Examples include the fire at the
Simi Valley Sodium Reactor in 1959, and the explosion at the 3MW experimental SL-1
reactor at the US National Reactor Testing Site in Idaho in 1961, which killed
three operators. Better known perhaps was and the core melt down of the Fermi
Breeder reactor near Detroit in 1966. Sodium fires have been a major problem
with many of the subsequent fast neutron reactor projects around the world, for example
in France, Japan and Russia.
For
good or ill, ideas like this are back on the agenda, albeit in revised forms.
That includes the currently much
promoted idea of scaling down to small modular reactors- SMRs. In theory they
can be mass produced, so cutting costs. Not everyone is convinced: scaling down doesn’t necessarily reduce
complexity and it’s that that may be the main cost driver. One cost offsetting option is to locate them
in or near cities so that the waste heat they produce can feed into district
heating networks. But given the safety and security risks, will anyone accept
them in their backyard? And like all nuclear plants, they will produce
dangerous long lived wastes that have to be dealt with.
Fast neutron breeder reactors can produce new plutonium fuel from otherwise unused uranium 238 and may also be able to
burn up some wastes, as in the Integral Fast Reactor concept and also the
Traveling Wave Reactor variant. Molten Salt Reactors using thorium may be able
to do this without producing plutonium or using liquid metals for cooling. Both
approaches are being promoted, but both have problems, as was found in the
early days. Certainly fast breeder reactors were subsequently mostly sidelined
as expensive and unreliable. And as heightening nuclear weapons proliferation
risks. The US gave up on them in the 1970s, France and the UK in the 1990s.
Japan soldiered on, but has now abandoned its troubled Monju plant. For the
moment it’s mainly Russia that has continued, including with a molten lead
cooled reactor, although India also has a fast reactor programme, linked to its
thorium reactors plans.
Thorium was used as a fuel for some reactors
in some early experiments and is now being promoted again- there is more of it
available globally than uranium. But there are problems. It isn’t fissile, but neutrons, fast or slow, provided by uranium 235 or
plutonium fission, can convert Thorium 232 into fissile U233. However, on the
way to that, a very radioactive isotope, U232, is produced, which makes working
with the fuel hard. Another isotope, U234 is also produced by neutron
absorption. Ideally, to maximise U233 production, that should be avoided, but
experts are apparently divided on whether this can be done effectively.
The use of molten
salts may help with some of these problems, perhaps making it easier to play
with the nuclear chemistry and tap off unwanted by-products, but it is far from
proven technically or economically. The economics is certainly challenging. Nuclear plants of any sort
may not be competitive in the emerging electricity market, as renewables get
ever cheaper and their market share expands, but some nuclear options might be
able to compete in the heat and synfuel markets. However, even that is unclear-
renewables may also be able to compete in meeting these end uses, with fewer
side effects.
Back in the
1950s, President Eisenhower launched Atoms for Peace
initiative, promising US aid with the world-wide development of bountiful
nuclear energy, and that idea has lingered on. In 2006, under the Global Nuclear Energy Partnership (GNEP) backed
by President George W Bush, US Energy Secretary Samuel Bodman said that ‘GNEP brings the promise of virtually
limitless energy to emerging economies around the globe’. After Fukushima and the economic challenges to nuclear
presented by gas and renewables, GNEP was in effect abandoned and we don’t hear
rhetoric like that so much: nuclear is on the defensive, only supplying 11% of
global electricity as against 25% from renewables, with the cost of the later
falling rapidly, while nuclear costs seem to be rising inexorable. Whether the
new Generation of fission technologies will be able to resuscitate it remains
to be seen. It doesn’t seem a good bet: http://science.sciencemag.org/content/354/6316/1112.1 And if you still have hopes for fusion, see this: http://thebulletin.org/fusion-reactors-not-what-they’re-cracked-be10699
All this and more is covered in my new IOPP book ‘Nuclear Power: Past, Present and
Future’: http://iopscience.iop.org/book/978-1-6817-4505-3
*If you are a real devotee of nuclear history, take a look at this new
long, partisan and somewhat overwhelmingly chaotic video selling thorium molten
salt reactors: https://www.youtube.com/watch?v=H6mhw-CNxaE
