JV formed to upgrade Kashiwazaki-Kariwa unit 6

03 June 2020

Tepco Holdings Corporation and Toshiba Energy Systems Corporation have agreed to establish a joint venture company to conduct safety upgrade work at unit 6 of the Kashiwazaki-Kariwa nuclear power plant. Tepco plans to restart units 6 and 7 of the plant, which is in Japan's Niigata Prefecture.

Units 5-7 of the Kashiwazaki-Kariwa plant (Image: Tepco)

"Tepco and Toshiba ESS have brought together technologies and knowledge that cross industry boundaries to jointly establish a company responsible for safety measures for Kashiwazaki-Kariwa nuclear power station unit 6," they said. "We have signed a memorandum of understanding regarding safety measures construction, design and management of construction."

The new company - KK6 Safety Measures Joint Venture Co Ltd (KS6) - is to be established this month. Each partner will invest JPY150 million (USD1.4 million) in the KS6 joint venture.

Kashiwazaki-Kariwa was unaffected by the March 2011 earthquake and tsunami which damaged the Fukushima Daiichi plant, although the plant's reactors were previously all offline for up to three years following the 2007 Niigata-Chuetsu earthquake, which caused damage to the site but did not damage the reactors themselves. While the units were offline, work was carried out to improve the plant's earthquake resistance.

Although it has worked on the other units at the Kashiwazaki-Kariwa site, Tepco is concentrating its resources on restarting units 6 and 7 while it deals with the clean-up at Fukushima Daiichi. Restarting those two Kashiwazaki-Kariwa units - which have been offline for periodic inspections since March 2012 and August 2011, respectively - would increase the company's earnings by an estimated JPY100 billion (USD921 million) per year.

In December 2017, Tepco received approval from the Nuclear Regulation Authority to change the installation of units 6 and 7. They were the first of the country's boiling water reactors determined to meet the standards.

Researched and written by World Nuclear News