Although derived from marine propulsion systems, the VBER-300 also incorporates features from the larger Russian VVER reactor designs. The reactor core is composed of 85 hexagonal fuel elements similar in design to VVERs. Each element contains 312 pins of less than 5% enriched UO2 fuel. Soluble boron in the primary coolant

is used in addition to the 48 control rods and distributed gadolinium pins to control reactivity. Each steam generator is composed of 55 individual once-through coil-type cassettes with the feed water and outlet steam partitioned into three independent headers. The primary coolant flows over the shell-side of the steam generator cassettes. The external vessels are flanged very close to the reactor pressure vessel to reduce the likelihood of leaks or large-break loss-of-coolant accidents.

The VBER-300 is being designed for maximum flexibility as either a ground — based stationary plant or a floating plant and can be used for electricity generation only or as a co-generation plant for electricity and heat for water desalination, district heating or industrial applications. It is also being designed to be scaled to different capacities by using between two and six heat exchanger loops. If used for co-generation, steam is extracted from the low-pressure turbine with a commensurate loss of electrical output. The containment for the ground-based plant is a large-volume steel-lined concrete structure that is 34 m diameter by 42 m tall. Key parameters and a representative graphic for the VBER-300 design are given in Figure 2.9. [6]