26.08.2015   The Future of Nuclear Power

VHTR (Gen IV)

The very high temperature reactor (VHTR) has been put forward by the GIF members as part of their Generation IV programme (The US Generation IV Implementation Strategy, 2003; Figure 12.2). This could be used for high efficiency electricity production but is also

Table 12.3. High temperature gas reactors

Reactor

Rating (MWe)

Country

VHTR (Gen IV)

~ 300

GIF members

GT-MHR

293

US/Russia/France/Japan

PBMR

120

South Africa/Consortium

Data from IEA/OECD (NEA)/IAEA (2002), The US Generation IV Implementation Strategy (2003), Squarer et al. (2001) and 18th Meeting of the Technical Working Group on Gas Cooled Reactors.

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Figure 12.2. Very high temperature reactor. Source: NEA Annual Report (2002).

seen as a good candidate for hydrogen production by thermochemical water splitting or through high-temperature steam electrolysis. The reference reactor is a 600 MWt helium — cooled reactor with a coolant outlet temperature of 1000°C or more with a design efficiency of 50%. At this efficiency, it could produce 200 metric tonnes of hydrogen per day. This technology requires advances in high-temperature materials, alloys, ceramics and composite materials.

The VHTR is seen as a natural development of the gas turbine modular helium reactor (GT-MHR) and PBMR reactor designs out lined below. These designs are the latest in evolutionary high-temperature reactor technology that are being proposed for short — to medium-term deployment.