Japanese officials have approved the re-start of a nuclear reactor for commercial purposes for the first time since the March 11 earthquake and tsunami.

The energy ministry was expected to issue a safety certificate authorizing operations later Wednesday after the governor of Hokkaido prefecture announced she has no objection to the move.

Only 15 of Japan's 54 nuclear reactors are operating normally, forcing citizens and companies to economize on air conditioning and other electrical use during one of the country's hottest summers.

However the decision will not immediately affect electrical output as the Hokkaido plant has been operating at full capacity in “test status” for months.

Nevertheless, the decision could help clear the way for other governors to authorize plant start-ups in spite of high public anxiety about nuclear power. Hokkaido Governor Harumi Takahashi made her decision only after conducting public meetings on the issue.

The government has ordered stress tests on all nuclear plants in Japan to ensure they are not vulnerable to the type of accident that struck the Fukushima Daichi plant on March 11.

The tsunami knocked out power to the cooling systems at the plant, resulting in core meltdowns in three of its six reactors. Officials are still struggling to bring the plant to a safe state while radiation continues to leak into the air, ground and water.