The Generation IV Initiative

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Generation IV systems are intended to improve significantly on current Generation III systems, which comprise advanced light water reactors (ALWRs) (Fig. 13.2) in terms of cost, safety, environmental performance and proliferation resistance (Abram and Ion, 2008). The Generation IV International Forum (GIF) is an international body established to carry out the research needed to establish the feasibility and potential performance of this next generation of nuclear power plants. The GIF Charter was signed in July 2001 by thirteen countries: Argentina, Brazil, Canada, France, Japan, the Republic of South Korea, South Africa, the United Kingdom and the United States. The Charter was later signed by Switzerland in 2002, Euratom in 2003 and, in 2006, the People’s Republic of China and the Russian Federation. In early 2006 the US also proposed a global nuclear energy partnership (GNEP) with a similar goal of delivering a sustainable and proliferation-resistant fuel cycle. GIF expects the first Generation IV systems to come on stream by 2030. Interim systems may be developed by the nuclear industry in the next 15 years, but these are not considered to be true Generation IV systems (Abram and Ion, 2008).

13.2 Historical evolution of nuclear reactors.

In 2009 GIF set the following criteria for any Generation IV system (Generation IV International Forum, 2009):

• Safety and reliability: Generation IV nuclear energy system operations will excel in safety and reliability. They will have a very low likelihood and degree of reactor core damage and will eliminate the need for offsite emergency response.

• Economics: Generation IV nuclear energy systems will have a clear life-cycle cost advantage over other energy sources. They will have a level of financial risk comparable to other energy projects.

• Sustainability: Generation IV nuclear energy systems will provide sustainable energy generation that meets clean air objectives and provides long-term availability of systems and effective fuel utilization for worldwide energy production. They will minimize and manage their nuclear waste and notably reduce the long-term management burden, thereby improving protection for the public health and the environment.

• Proliferation resistance and physical protection: Generation IV nuclear energy systems will increase the assurance that they are very unattractive and the least desirable route for diversion or theft of weapons-usable materials, and provide increased physical protection against acts of terrorism.

GIF has identified six nuclear energy systems for further development that have the potential to meet these criteria. These use a range of reactor sizes and types, energy conversion technologies, and open and closed fuel cycles. The six reactor types are:

• VHTR: very high-temperature reactor

• SCWR: supercritical water reactor

• MSR: molten salt reactor

• SFR: sodium-cooled fast reactor

• LFR: lead-cooled fast reactor

• GFR: gas-cooled fast reactor

All of these systems have been studied and, in many cases, experimental or prototype systems established. Each system has its strengths and weaknesses. The capacity of each system to meet the criteria set out by GIP is summarized in Table 13.3. GIF expects that, depending on initial results, it will eventually narrow the selection down to two or three systems for further commercial development. It is important to note that Generation IV systems will need to address all the aspects of nuclear power generation, from the mine to the final disposal of waste. They will need to address the whole fuel cycle as well as the building and disposal of plant. This life-cycle approach makes Generation IV systems (and connected initiatives such as GNEP) different from previous generations. An overview of the whole fuel cycle R&D requirements is given in Table 13.4. The following section discusses these common requirements for any Generation IV system.

Table 13.3 Potential of each system to meet Gen IV goals

Generation IV goal

VHTR

SCWR

MSR

SFR

LFR

GFR

Efficient electricity generation

high

high

high

high

high

high

Availability of high-temperature process heat

very

high

low

medium/

low

medium

medium

high

Creation of fissile material

medium

low

medium

high

high

high

Transmutation of

medium/

low

very

very

very

very

waste

high

high

high

high

high

Potential for passive safety

high

very

low

low

medium/

low

medium

low

Current technical feasibility

high

medium

low

high

medium/

high

medium

Table 13.4 Gen IV crosscutting fuel cycle R&D needs (Generation IV International Forum, 2002)

Generation IV System

Fuel

Recycling

Oxide

Metal

Nitride

Carbide

Advanced

aqueous

Pyroprocess

GFR1

S

P

P

P

MSR2

SFR3

P

P

P

P

LFR

S

P

P

P

SCWR

P

P

VHTR4

P

S

S

Notes:

P: Primary option S: Secondary option

1 The GFR proposes (U, Pu)C in ceramic-ceramic (cercer), coated particles or ceramic-metallic (cermet).

2 The MSR employs a molten fluoride salt fuel and coolant, and fluoride-based processes for recycling.

3 The SFR has two options: oxide fuel with advanced aqueous, and metal fuel with pyroprocess.

4 The VHTR uses a once-through fuel cycle with coated (UCO) fuel kernels, with no need for fuel treatment, as the primary option.

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