Utilizing the wealth of skills, knowledge and experience of several senior engineers in the nuclear industry, IST's Nuclear Systems group was created in the late 80's. Nuclear Systems' initial focus was on projects for the former Atomic Energy Corporation of South Africa (AEC) and later the Koeberg Nuclear Reactor in the Cape. During the 1990's, however, the focus shifted towards one of the world's most exciting nuclear projects, the Pebble Bed Modular Reactor (PBMR).

Starting in 1990, IST Industrial invested material funding and manpower in conceptualising, designing and developing the direct cycle, high temperature helium gas cooled nuclear reactor technology for commercial applications. The heat source selected was the Pebble Bed Reactor as developed and succesfully demonstrated by German technology during the previous three decades until 1989. The direct cycle power conversion unit (PCU) was IST's innovation. The concept became known as the South African PBMR. The concept was presented to Eskom (South Africa's national electricity supplier) and since 1993 the PBMR project has been under on-going investigation as part of Eskom's integrated electricity planning process.

In 1995, Eskom requested that IST Industrial perform a pre-feasibility study, followed by a techno-economic study completed in 1997. The full-scale engineering design phase followed, with IST being actively involved, initially in developing the engineering concepts at plant level, and later as a potential turnkey supplier of the Main Support Systems of the PBMR.

As part of the Detailed Feasibility Study of the PBMR, conducted during 2000/2001, IST was responsible for the basic design and costing of its sub-systems, namely the Fuel Handling and Storage System (FHSS), the Reactivity Control and Shutdown System (RCSS) and the Gas Systems.