Increasing redundancy keeps nuclear plants safe

Published August 6, 2017, 10:00 PM By Myrna M. Velasco

http://business.mb.com.ph/2017/08/06/increasing-redundancy-keeps-nuclear-plants-safe/

Ljubljana, Slovenia – With extreme weather swings and catastrophic disasters that could hit on energy facilities, nuclear plants have been installing multiple redundancies in their plant control systems as well as additional safety measures to prevent disastrous meltdown of their reactors.

This is the key lesson set off by the Fukushima Dai-ichi nuclear tragedy in 2011 and a cautionary measure for countries wanting to go into nuclear power program, according to Dr. Andrej Stritar, Director at Slovenia’s Nuclear Safety Administration, the regulatory agency of this country’s nuclear power program.

“Everywhere in the world where there are nuclear plants in operation, a lot had been invested for additional protective measures after the Fukushima incident… in our case in Slovenia, we have invested several hundred millions of euros,” he said.

At Slovenia’s 730-megawatt Krško nuclear power plant, he noted that the government pumped in $200 million to $300 million additional multi-year investments to enhance the nuclear plant’s redundancies, or the back-up systems that could keep the plant off from operational failure.

The Krško plant was recently visited by officials of the Philippine Department of Energy (DoE) to learn the lessons it had adhered to on its years of operations – as this is a facility utilizing the same Westinghouse pressurized water reactor and almost of parallel age as the Bataan Nuclear Power Plant.

The Krško plant, which is now on its 35th year of operations would have been due to reach its 40-year decommissioning in year 2023, but regulatory agencies had just recently given go-signal for it to extend its operating life cycle by additional 20 years or until 2043.

Throughout the nuclear facility’s more than three decades of operations, Sistrar noted that Krško had not experienced any major industrial mishap, as he emphasized on their “very deep culture of safety” in operating the plant because it sits on an earthquake fault.

“We have been constantly examining the most vulnerable things that could affect its operations. We are calculating probability of accidents because they could happen anytime,” he said.

Sistrar reminded though that even the Fukushima nuclear tragedy had not been caused by an earthquake, but by the strike of tsunami – which at that time had been among the “external influences” that even Japan had not known or experienced yet on its stretch-decades of nuclear plant operations.

“Safety on nuclear power plant operations is of crucial importance with all these external influences, including earthquakes. But there are solutions and there are methods to keep the facilities safe and secure,” he stressed.

Sistrar noted two paramount reinforcing features or back-up assets critically required to be on-site in nuclear plant operations – that there should an on-the-fence diesel generating facility and a water source close to the facility.

“It is important that you have water source and you have electricity to pour that water in into the nuclear reactor in case of a meltdown… so these two are very important to be there in a power plant site,” he said.

As Krško nears the culmination of its initial 40-year operation, the host governments of Slovenia and Croatia had spent five years of study and data gathering as well as securing community approval for the establishment of its radioactive waste and spent fuel repository.