Nuclear Production of Hydrogen, Fourth Information Exchange ...

CHANGING THE WORLD WITH HYDROGEN AND NUCLEAR: FROM PAST SUCCESSES TO SHAPING THE FUTURE
was first used to power military ships and submarines, and it was then applied to develop more
economically competitive power reactors that still constitute more than 80% of the world generating
fleet today.
Naval reactors
The nuclear aircraft carrier USS Enterprise in 1964 had its crew members spell out Einstein’s
mass-energy equivalence formula E = mc 2 on the flight deck.
Nuclear rockets
Secondly, the nuclear rocket programme ROVER/NERVA that was developed from the 1960s up to 1973
for defence applications and exploration of space combined a core designed for an extreme power
density and the use of hydrogen as coolant and propellant. The advantage of hydrogen here was its
low molecular weight that assured maximum specific impulse at a given outlet temperature and its
storability as a liquid at cryogenic temperature. Ground tests of nuclear rocket engines demonstrated
ejection temperatures well above 2 100°C and specific impulses of the order of 800-900 seconds. The
successful test at 5 000 MWth of the Phoebus 2A in 1968 still remains today the world record of
thermal nuclear power.
Controlled fusion
Thirdly, the understanding of fusion reactions in the sun by Hans Bethe triggered the interest in
controlled thermonuclear fusion through both the magnetic and the inertial approaches. Two isotopes
of hydrogen, deuterium and tritium, are rapidly identified as being the less demanding in terms of
temperature and confinement requirements to achieve fusion, due to the low electric charge of their
nucleus that minimises the energy needed to overcome their electrostatic repulsion. First tests of
fusion reactions with D-T plasmas occurred in the Joint European Torus (JET) in the 1990s, and this is
the goal of ITER to demonstrate the controllability of a D-T plasma in a close to ignition sustained
operating mode.
These three forms of nuclear systems make respective use of hydrogen as neutron moderator,
coolant and nuclear fuel.
The PNP-500 project
The fourth breakthrough with hydrogen and nuclear that was well on track in the 1980s consisted in
the Power Nuclear Project (500 MWth) in Germany that aimed at using nuclear heat to produce
hydrogen with the process of steam methane reforming. This project led to develop and test large
modules of heat exchangers and steam reformer in the facilities EVA on the research centre of Jülich
and KVK at Interatom in Bensberg. The whole programme stopped in the late 1980s shortly after the
decision to shutdown prototypes of high temperature reactors both in Germany and the United States.
Over the 20 th century, hydrogen and nuclear had been instrumental as alternative energy sources
to fossil fuels and as enabling technologies for specific and strategic applications such as space
missions and propulsion of surface ships and submarines. New concerns that emerged in the
21 st century about the growth potential and the sustainability of all energy production means call for a
stronger role of hydrogen and nuclear energy in the future energy system.
Stakes in hydrogen and nuclear production in the 21 st century
Energy challenges for the 21 st century
Indeed, the beginning of the 21 st century faces a number of real new challenges to meet the world
energy demand.
First, the increasing world population and the rapid economic development of large countries
such as China and India cause a fast-growing energy demand and rising concerns of energy security:
How will political constraints impact our access to oil and gas? Will prices of energy remain affordable
for our economies in spite of political constraints and needs for investments to exploit new resources?
26 NUCLEAR PRODUCTION OF HYDROGEN – © OECD/NEA 2010