Nuclear Production of Hydrogen, Fourth Information Exchange ...

EXECUTIVE SUMMARY
Executive summary
Session 1: Programme overviews
Chairs: Yoshiyuki Nemoto (OECD/NEA), Carl Sink (US DOE)
Programme overviews from USA, France, Japan, Korea, Russia and Canada were presented in
Session 1.
As less than 30% of the thermal energy from a nuclear power plant is used to generate electricity,
nuclear production of hydrogen should be developed to utilise the remaining energy. This would
especially be appropriate for some of the next generation high-temperature nuclear plants. It was
suggested that an economic and efficient use of thermal energy from a nuclear power plant would be
to utilise the surplus energy for hydrogen production during periods in which electricity consumption
is relatively low.
Outlines of research and development programmes for several nuclear hydrogen production
technologies, such as high-temperature steam electrolysis (HTE), and sulphur-iodine (S-I) and hybrid
sulphur (HyS) thermochemical processes were introduced. The panel discussion, which followed the
presentations, discussed the criteria for choosing the best hydrogen production system and suggested
that the selection would be judged mainly on economic criteria. Detailed information about the
economic analysis and considerations was presented in Session 5.
Potential future hydrogen applications were discussed. As a huge amount of CO 2 is emitted from
the transport sector, it would greatly reduce CO 2 emissions and prevent global warming if, for example,
hybrid automobiles could be fuelled by electricity from nuclear power plants, oil fuels made from
biomass and hydrogen produced by nuclear power plants. Other issues discussed by the panel related
to gasoline upgrading and iron production using hydrogen.
It was generally acknowledged that a sustainable energy production is required in the future.
From this point of view, the nuclear fuel cycle has to be further developed. Fast breeder reactor (FBR)
technology seems to be a good candidate for nuclear hydrogen production. However, other new reactor
concepts, such as high-temperature gas-cooled reactors (HTGR) and supercritical water-cooled reactors
(SCWR) have some advantages for hydrogen production, and further analysis is therefore required.
Session 2: High-temperature electrolysis
Chairs: Yoshiyuki Inagaki (JAEA), J. Stephen Herring (INL)
Seven papers were presented during Session 2. Dr. James O’Brien of the Idaho National Laboratory
began with a summary of the status of research on high-temperature electrolysis at the INL. He included
a discussion of the systems’ analysis results, comparing the efficiency of hydrogen production using
air, steam or nothing as the sweep gas for the oxygen. He also compared the hydrogen production
efficiency using low-temperature electrolysis, high-temperature electrolysis and the S-I process for a
range of reactor outlet temperatures from 400-1 000°C. The HTE efficiencies were between 40-60% for
temperatures above 600°C. Dr. O’Brien then reviewed the recent results from the INL Integrated
Laboratory Scale (ILS) experiment. This experiment, using three modules of 240 cells each, initially
produced 5.6 Nm 3 /hr at a power of 18 kW. Over the course of the 1 080-hour experiment the H 2
production dropped to about 0.8 Nm 3 /hr due to the increase in cell resistance.
Dr. Julie Mougin of the CEA Grenoble Laboratory described research on a low-weight stack and on
materials for better efficiency and durability. The central experiment in answering both questions is
NUCLEAR PRODUCTION OF HYDROGEN – © OECD/NEA 2010 9