Japan's Kansai Elec submits 2nd nuclear reactor test results

* Move is part of initial step in restoring public faith in nuclear power

* Kansai Elec submitted test results on 1st reactor on Oct 28

* Not yet clear which reactors will restart first

TOKYO, Nov 17 (Reuters) - Kansai Electric Power Co said on Thursday it had submitted the results of first-stage stress tests on a second nuclear reactor, part of an initial step in rebuilding public faith in atomic energy.

No reactors taken offline for routine maintenance have been restarted since a massive earthquake and tsunami in March triggered reactor meltdowns and the world's worst radioactive material leakage in 25 years at Tokyo Electric Power Co's Fukushima Daiichi station in the northeast.

The western Japan utility said it submitted the results of tests on the 1,180 megawatt No.4 reactor at its Ohi nuclear plant to the Nuclear and Industrial Safety Agency (NISA).

Kansai on Oct. 28 filed the results of tests on the 1,180 MW No.3 unit at the same plant in Fukui prefecture, becoming the first nuclear generator to do so.

Kansai is among the utilities looking to get reactors back online to help meet peak winter demand in January and February.

But it is not yet clear when the NISA and its supervisors, including Prime Minister Yoshihiko Noda, will approve the stress test reports and when approvals by local authorities will pave the way for the reactor restart.

"Supply and demand conditions are tight. We've been doing tests on each reactor as we'd like to see (NISA) completing the assessments as early as possible," a company spokesman said.

Currently, only 11 reactors with a capacity of 9,864 megawatts are generating electricity.

Five more reactors, of which three are Kansai's, are set to enter regular maintenance by the end of the year, which would leave just 11 percent of the country's total nuclear power capacity in use at that point.

Earlier this week, Shikoku Electric Power Co, another highly nuclear reliant utility in the west, submitted first-stage stress test results on the 890 MW No.3 reactor at its sole Ikata plant in Ehime prefecture.

First-stage tests are on idled reactors which are ready to restart and second-stage tests apply to all reactors.

The stress tests evaluate each reactor's resilience to four severe events -- earthquake, tsunami, station blackout and loss of water for cooling -- and a reactor operator's management of multiple steps to protect reactors. (Reporting by Risa Maeda; Editing by Joseph Radford)