Tokyo Electric Power Co. officially declared Wednesday that the two reactors that suffered no major damage at the Fukushima No. 1 plant in the 2011 disaster are defunct, meaning the nation will have only 48 operable commercial reactors.

“With this decision, all of the plant’s six reactors will be classified as defunct,” Tepco said in a press release following a meeting of its board. “It is extremely regrettable that we hugely betrayed the local people’s trust due to the accident and are deeply ashamed of ourselves.”

Reactors 5 and 6 will be classified as defunct on Jan. 31, but instead of dismantling them, Tepco may use them as experimental facilities to support the challenging task of scrapping the three reactors that experienced meltdowns and the other one crippled by a hydrogen explosion.

The public has been demanding that Tepco scrap both the Fukushima No. 1 and nearby Fukushima No. 2 plants. The utility has not made clear what it intends to do with the four-reactor Fukushima No. 2 complex, located about 12 km south of the crisis-ridden Fukushima No. 1 facility.

As new accounting rules regarding decommissioning came into force in October, Tepco is likely to avoid booking a large extraordinary charge for the current business year through next March due to a shortfall in funds for decommissioning.

“We are currently examining the impact of the latest decision on our accounting,” Tepco said.

After the Fukushima No. 1 plant was hit by the March 11, 2011, magnitude 9.0 earthquake and tsunami, reactors 1, 2 and 3 experienced core meltdowns. And the building housing reactor 4, which did not have fuel inside its core because it was under maintenance, was damaged by a hydrogen explosion.

But reactors 5 and 6, which were also under maintenance at the time of the earthquake, achieved cold shutdowns through the use of an emergency diesel generator that avoided flooding.

Reactors 1 to 4 were deemed defunct in April last year. In September, Prime Minister Shinzo Abe visited the severely damaged nuclear plant and urged Tepco to also scrap reactors 5 and 6 as well, saying the utility should focus more on the crisis cleanup efforts. Just scrapping the crippled reactors alone will take decades, and radiation levels in and around them will remain dangerous at least over that time.

Fukushima No. 1 is Tepco’s first nuclear power station. It started commercial operation in 1971. Electricity supplied by the plant supported the economy after the oil crisis in the 1970s, said Tepco, which serves Tokyo and nearby areas.

Tepco is seeking to bring its remaining Kashiwazaki-Kariwa nuclear plant in Niigata Prefecture back online to improve its tough business condition in light of the nuclear crisis.

The utility estimates that if it can restart that plant’s reactors 6 and 7 as planned, it can cut between ¥240 billion and ¥330 billion annually in fuel costs for thermal power generation.

Tepco has been under effective state control after receiving a ¥1 trillion capital injection from a government-backed fund.