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Source of power has been a hot topic for many years. There have been demands for renewable energy to slow down the rate of global warming. Power problems, such as resent events in South Africa, have also demonstrated the need to find quick, cheap, safe and eco-friendly power.

The Pebble Bed Modular Reactor (PBMR) is a new type of high temperature helium gas-cooled nuclear reactor, which builds and advances on world-wide nuclear operators' experience of older reactor designs. The most remarkable feature of these reactors is that they use attributes inherent in and natural to the processes of nuclear energy generation to enhance safety features.

It is also a practical and cost-effective solution to most of the logistics of generating electricity, with particular reference to South Africa today.

Overview

PBMR fuel is based on a proven, high-quality German fuel design consisting of low enriched uranium triple-coated isotropic (LEU -TRISO) particles contained in a moulded graphite sphere. A coated particle comprises a kernel of uranium dioxide surrounded by four coating.

The design aims to achieve lower risks and higher thermal efficiencies than possible in traditional Nuclear Power Plants. Instead of water, it uses pyrolytic graphite as the neutron moderator, and an inert or semi-inert gas such as
helium, nitrogen or carbon dioxide as the coolant, at
very high temperature, to drive a turbine directly.
This eliminates the complex steam management
system from the design and increases the thermal
efficiency (ratio of electrical output to thermal output)
from 32-35% to 40-50%. Also, the gases do not
dissolve contaminants or absorb neutrons as water
does, so the core has less in the way of radioactive
fluids and is more economical than a light water
reactor.

The uranium, thorium or plutonium nuclear fuels...