The operator of Japan's crippled Fukushima nuclear power plant posted a solid mid-term pre-tax profit Friday, despite not restarting idle nuclear reactors or hiking electricity rates.

The striken Tokyo Electric Power Co. (TEPCO) refrained from making full-year projections, saying it is difficult to do so while its workhorse nuclear plant remains offline following the March 2011 earthquake-tsunami disaster.

TEPCO said it chalked up a group pre-tax profit of 242.8 billion yen ($2.23 billion) in the April-September period, up 71.4 percent from a year earlier.

It attributed the solid result to postponed construction of power plants and cuts in manpower and material costs.

Its revenue rose 3.7 percent to 3,334 billion yen despite a decline in the volume of electricity sales in an unusually cool summer.

But TEPCO declined to predict earnings for the year to March 2015 as its Kashiwazaki-Kariwa nuclear power plant in Niigata also remains offline and the effects of its cost-cutting efforts remained to be seen.

The utility giant had initially projected that its annual group pre-tax profit would reach 167.7 billion yen if some of the plant's seven reactors were refired in July.

TEPCO was forecast to book a pre-tax profit of 130 billion yen for the full year, topping 100 billion yen for a second straight year, Kyodo news agency said last week.

In the year to March 2014, TEPCO posted a pre-tax profit of 101.42 billion yen against a loss of 326.96 billion yen the previous year.

The utility had warned it would suffer a 15 billion yen pre-tax loss if the plant remained idle and electric rates stayed unchanged.

A massive earthquake and tsunami wrecked Fukushima's cooling systems in March 2011, sparking off reactor meltdowns and radiation leaks.

Japan shut down all 48 of its reactors in the wake of the Fukushima crisis, the worst nuclear accident since the 1986 Chernobyl disaster.

The government and power utilities would like to fire some of them up again despite public uneasiness. The reactors would have to clear tough safety requirements introduced after the Fukushima crisis.

The government has poured billions of dollars into TEPCO to keep the company -- that supplies electricity to Tokyo and its surrounding area -- afloat as it stumps up cash for decommissioning the reactors, cleaning up the mess from the 2011 disaster and paying compensation.