Status of the Generation IV Initiative on
Future Nuclear Energy Systems

Frank Carré and Gian Luigi Fiorini
CEA/Nuclear Energy Division

Last updated: 21 April 2004.



The US Department of Energy (DOE) launched the Generation IV initiative in 2000. Today, it groups 10 member countries plus Euratom, with the aim of developing innovative nuclear systems (reactors and fuel cycles) likely to reach technical maturity by 2030. (The ten countries are: Argentina, Brazil, Canada, France, Japan, the Republic of Korea, the Republic of South Africa, Switzerland, the United Kingdom and the United States.)

Six nuclear systems were selected; they aim at considerable improvements in economic competitiveness, in safety, in uranium resource economy and in reducing long-life radioactive waste. A technology roadmap (nuclear.energy.gov/genIV/documents/gen_iv_roadmap.pdf), initially prepared at the request of the US Congress, is now used as a basis to structure and share the R&D effort among the participating countries, in order to develop the selected nuclear systems.

In the future, other countries or international authorities could join the Generation IV International Forum and the related R&D effort.

1. Generation IV – pooling international R&D

The founding principle of the Generation IV International Forum (GIF) is its members’ recognition of nuclear technologies’ role in satisfying the world’s increasing energy needs – in the context of sustainable energy development and climate change prevention. This principle, laid down in the GIF charter, expresses a common will to create a framework for international R&D. This framework’s role is to define, develop and enable the deployment of Generation IV nuclear systems. Most of the research involved will develop within this multilateral framework, over the coming decades.

2. What is Generation IV?

Nuclear systems can be classified according to the generation they belong to. The US DOE distinguishes four generations:

  • Generation I was operational before the 1970s and made use of natural uranium, to avoid the need for enrichment;

  • Generation II comprises light water reactors deployed since the 1970s. They are still in operation;

  • Generation III involves optimising the current reactors, in terms of economics and safety. These reactors are likely to be deployed before 2010;

  • Generation IV comprises nuclear systems likely to reach technical maturity by 2030. Their design will take cognisance of the progress made in economics and safety. In addition, the aim is for these reactors to support sustainable energy development worldwide, and to open up the range of nuclear systems’ applications to hydrogen generation for transport (in addition to electricity production).

3. Generation IV’s goals

International consensus has been reached on the on the general goals and criteria to be met by Generation IV nuclear systems. They will have to be:

  • sustainable: the systems should offer efficiency in the use of the natural resources, and should minimise environmental impact (and, at the same time, minimise waste in terms of mass, radio toxicity, residual power, etc.);

  • economically viable: economic considerations are: the generating cost, which should be competitive when compared with other energy sources; and the capital investment cost, which should be low enough for the nuclear system under development to remain accessible to a large number of countries (total investment cost and specific investment cost ($/kWe) refers);

  • safe and reliable: it is mandatory that future reactors perform at least as well in terms of safety and reliability as current reactors. In particular, key focus is to be placed on eliminating, as far as possible, the need for public evacuations from areas outside nuclear sites – in the event of an accident, whatever its cause and extent of gravity;

  • resistant to proliferation risks and likely to be easily protected from external attack.

Besides electricity generation, the Generation IV systems will offer potential for the generation of hydrogen from water for use in transport, seawater desalination, and heat generation for industrial processes.

4. The selection of Generation IV systems

From April 2001 to October 2002, technologies likely to meet the above-mentioned criteria were identified by means of the roadmap. The six selected concepts will be developed, in multilateral co-operation, during a second phase of the Forum’s activity.

The six concepts, as presented in Figure 1, are:

  • GFR: Gas-cooled Fast Reactor system cooled with helium;

  • LFR: Lead Fast Reactor cooled with lead or lead-bismuth eutectic;

  • MSR: Molten Salt Reactor fuelled with molten salts;

  • SFR: Sodium Fast Reactor;

  • SCWR: Super-Critical Water-cooled Reactor;

  • VHTR: Very High Temperature Reactor cooled with helium at 1000°C at the core outlet, for efficient production of hydrogen.

Generation IV

Among the six selected systems, three have fast neutron spectra: the GFR, SFR and LFR. Two advanced gas-cooled systems (GFR and VHTR) rely on R&D which, to a large extent, follows the same path. The SCWR was retained with a thermal neutron spectrum as an intermediate step and a fast neutron spectrum as an ultimate goal. The MSR stays in the running as a non-conventional system. With the exception of the VHTR, all these systems will be operated with a closed fuel cycle.

Key comments relevant to the selection of the six Generation IV systems:

  • among the retained goals and criteria, sustainability has been the most discriminating. This is demonstrated by the majority of the systems having fast neutron spectra and closed fuel cycles.

  • the grouping of systems in families – according to homogeneity in performance and R&D needs – turned out to be important for optimising R&D efforts and structuring recommendations along the lines of federal guidelines.

  • selecting two gas-cooled systems (GFR and VHTR) was an acknowledgement of the interest in this coolant for high temperature applications. A strongpoint governing this selection is the consistency of the technology they employ, enabling a sizeable common R&D pathway to be followed.

  • the issues which prevented the more innovative systems from being selected concerned important uncertainties on: their definition and performance, as well as on the prospects of overcoming obstacles to their viability before the 2030 realisation deadline.

The European participants in the project’s ‘technology roadmap phase’ (i.e. France and the United Kingdom as GIF members, and the European Commission as an observer) played a vital role. Actively emphasising the significance of sustainability issues, they also advocated selecting Generation IV systems which, historically, have been developed in Europe – and result from expertise which is essentially European. This and the existence of a European HTR network, place GIF’s European partners in a strong position to significantly contribute to the two Generation IV advanced gas-cooled systems. Countries such as France and the United Kingdom also plan to give national support to developing a new generation of sodium-cooled fast reactors. Lower priority has been given to supporting R&D work on supercritical water-cooled reactors, lead-cooled fast reactors and molten salt reactors, which are already the subject of initiatives taken under the European Commission’s 5th Framework Programme (FP5).

5. A shared R&D effort

Two main phases of R&D were identified:

  • the ‘feasibility phase’ dedicated to resolving technology showstoppers;

  • the ‘performance phase’, aiming at confirming and optimising the systems’ performance (which was the criterion emphasised in the selection process).

The feasibility studies for the more mature systems – i.e. the Sodium Fast Reactor (SFR) and the Very High Temperature Reactor (VHTR) – should last until 2008 and 2012 respectively; and the performance studies, until 2015.

As regards the more futuristic systems – i.e. those having fast neutrons and gas coolant (GFR), lead (LFR) and supercritical water (SCWR) – the feasibility studies will proceed until 2013 and 2015, and the studies of optimisation until 2020. The timeline for the molten salt system will be longer.

While nuclear R&D organisations will play an essential role in both the feasibility and the performance studies, there will be substantial participation from universities, other research organisations and manufacturers. Countries that are not currently GIF members will be able to join the R&D effort at this stage.

Following the feasibility and performance phases, it is expected that international consortiums of manufacturers and R&D laboratories will support demonstrations of the key technologies. They will also identify which Generation IV systems they are interested in launching commercially.

6. Progress in preparing for the next phase of GIF

The GIF Policy Group meeting, held in Zurich on 26-27 January 2004, led to progress on three main topics: the co-operation agreement at system level, the governance of the Forum, and relations with other organisations.

In Zurich, the US DOE presented a draft system agreement – jointly prepared by its State and Trade Departments – covering the first 10 years of co-operation (and providing for extensions in five-year increments). This project of agreement will establish the R&D framework required to address Generation IV system feasibility issues, as well as to confirm system performance, established during the system selection process. Future phases of demonstrating and commercialising the six selected nuclear systems will be the subject of further agreements. The parties to this system agreement are intended to be governmental entities or mandated national laboratories. GIF members are to be invited to give their input on the draft system agreement, which is expected to be finalised by mid-2004.

As regards the organisation and the governance of the GIF, the principles proposed at the previous meeting (on 24-26 September 2003 in Toronto) were confirmed, and the main focus of the discussion was on the role of the OECD/NEA as support to the Technical Secretariat of the GIF. The following decisions were made:

  • W. Magwood of DOE was elected as the GIF Policy Group’s chairman, for three years. His appointment officially began on 1 January 2004, and he will be assisted by two co-chairmen: J. Bouchard of the French Atomic Commission, CEA and Y. Sagayama of JNC;

  • the principles of organisation and governance will be the subject of Policy Statements intended to complement the charter of the GIF;

  • a Policy Secretariat assists the chairman of the Policy Group during its three-year mandate, whereas a Technical Secretariat provides ongoing support to the technical activity of the GIF and centralises data integration.

  • the Policy Group confirmed the organisational structure (in Figure 2 below).

  • all GIF members agreed to give the mandate to the NEA to act as the Technical Secretariat.

Concerning the relationship between the GIF and the INPRO initiative, which falls under the auspices of the IAEA, a series of meetings and exchanges have had the objective of defining those factors which are complementary and to provide project co-ordination:

  • INPRO is viewed as intending to refine users’ requirements and methodology, in order to assess the suitability of a nuclear technology to IAEA-affiliated countries and to facilitate exchanges of public GIF information to non-GIF member countries;

  • GIF will consider the users’ requirements developed by INPRO, especially with a view to enlarging the criteria to make the sustainability of nuclear power a reality.

R&D Organisation

Among the four GIF countries which are not INPRO participants (the United States, Japan, the United Kingdom and France), France is the only one which has decided
to join this initiative.

Furthermore, the GIF will benefit from the advice of a Senior Industry Advisory Panel constituting high-level representatives of the industry, in a position to make recommendations on long-term strategic considerations, including industrial, technical, commercial and statutory aspects. The GIF will also interact with the heads of GIF member countries’ safety authorities. A first exchange of this nature, involving GIF Policy Group members, took place at the Toronto meeting. At this meeting the importance of the IAEA safety standards were underscored as establishing reference criteria and contributing to international harmonisation.

Finally, the following progress has been achieved in preparing the R&D plans for Generation IV systems:

  • the Experts Group, which advises the Policy Group, reviewed the current version of the R&D plans drafted for the GFR, SCWR, SFR and VHTR systems, and, in December 2003, issued guidelines for the provisional Steering Committees for these systems to make improvements to these documents by mid-2004;

  • the Policy Group decided to set up a provisional Steering Committee for the Lead Fast Reactor, with the United States, Japan, South Korea, Switzerland, and Euratom as participants; and

  • establishing a Steering Committee for the Molten Salt Reactor, which was debated by the Policy Group in January, is to be re-examined at the next meeting (May 2004).

In conclusion, preparations for the GIF’s collaborative phase are actively progressing, both in terms of harmonising views on multilateral co-operation agreements, and sharing R&D work among the GIF member countries. This provides excellent prospects for the international development of the selected six Generation IV systems being initiated in 2004.








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