by Yavuz Arik, independent analyst

The potential for nuclear danger lies not in the newer designs and installations, but in the older designs that are being kept operating beyond their originally planned lifespan. The age of a nuclear power station also roughly distinguishes the level of design. Gen I (test reactors) was followed by Gen II (commercial energy reactors) until 1996. Hence any plant that is older than 27 years is a Gen II plant.

Eskom's Koeberg nuclear power station was built in 1985 and is therefore a Gen II design - Ed.

Gen III plants were first installed in 1996, and even though the first two installed in Japan were eventually taken down, to date, none of the Gen III plants have experienced any serious accidents. This is a testament to good design specs:
- Designed for 60 years of operation, extendable to 100+ years
- Designed for less than 1 core damage event in 1,66 million reactor years for pressurized water reactors (PWRs).
- Designed for less than 1 core damage event in 33 million reactor years for boiling water reactors (BWRs).

For the roughly 130 Gen III and III+ plants that are in operation worldwide, the joint design probability of a core damage event is 1 in 12 800 reactor years, using the lesser criteria for PWRs. If they were all BWRs, the probability would be as low as 1 in 256 000 reactor years. That is the low probability of any of the 130 reactors having a core problem in a given year!

Unfortunately, the same can't be said for Gen II plants. These plants require significant maintenance and supervision due to their age and older designs.

We are on the way to have even safer specs in place for all types of Gen IV reactors and SMRs (even safer than Gen III designs) within 10 to 20 years. Hence, we will need to bear with at most a 1 in 12 800 probability any given year with the current fleet, until they give way to even safer units designed as 'walk-away' safe, with no more need for huge and very costly containment structures.

Air travel on commercial jets is safer than ever thanks to technology that we all enjoy and don't even think twice about trusting on our holidays. Nuclear power will surely become as trusted in the near future, if nuclear plant producers keep implementing the most rigorous design criteria and all possible safety measures to prevent serious events from ever happening again.
 

Acknowledgment

This article was first published on LinkedIn