PBMR

Pebble Bed Modular Reactor (Pty) Ltd

Type	Engineering
Industry	Nuclear
Founded	1994
Headquarters	Centurion, Gauteng, South Africa
Area served	South Africa, International
Key people	CEO: Alex Tsela (acting since March 2010)
Services	Design, Project Management and Related Services
Number of employees	Est. 900, reduction to 9
Website	http://www.pbmr.com

The Pebble Bed Modular Reactor (PBMR) is a particular design of pebble bed reactor under development by South African company PBMR (Pty) Ltd since 1994. The project entails the construction of a demonstration power plant at Koeberg near Cape Town (now postponed indefinitely) and a fuel plant at Pelindaba near Pretoria.

The PBMR is characterised by inherent safety features, which mean that no human error or equipment failure can cause an accident that would harm the public.

Heat from the PBMR can be used for a variety of industrial process applications, including process steam for cogeneration applications, in-situ oil sands recovery, ethanol applications, refinery and petrochemical applications. The high temperature heat can also be used to reform methane to produce syngas (where the syngas can be used as feedstock to produce hydrogen, ammonia and methanol); and to produce hydrogen and oxygen by decomposing water thermochemically.

The PBMR is modular in that only small to mid-sized units will be designed. Larger power stations will be built by combining many of these modules. As of 2008, 400MWt was emerging as an optimum module size, considerably larger than the original concept size. The PBMR is fuelled and moderated by graphite fuel spheres each containing TRISO coated low enriched uranium oxide fuel particles. There are 15000 fuel particles per fuel sphere the size of a billiard ball. "Each fuel pebble contains 9 g of uranium, and this holds enough generation capacity to sustain a family of four, for a year. Five tons of coal and up to 23 000 m³ of water will be required to generate one pebble's energy.”

The concept is based on the AVR reactor and THTR in Germany, but modified to drive a Brayton closed-cycle gas turbine. The core design is annular with a centre column as a neutron reflector.

Since its establishment in 1999, Pebble Bed Modular Reactor (Pty) Ltd grew into one of the largest nuclear reactor design teams in the world. In addition to the core team of some nine hundred people at the PBMR head-office in Centurion near Pretoria, more than a thousand people at universities, private companies and research institutes were involved with the project.