The government is moving forward plans to change business operating hours for manufacturers, with the joint ministerial decree to take effect in Java and Bali from July 21 until the end of 2009.

Under the regulation, manufacturing companies will be obliged to move two working days each month to Saturday and Sunday.

A maximum violation of the decree will result in a temporary cut in electricity supply, but no incentives will be given for compliance, despite earlier announcements.

Industry Ministry secretary-general Agus Tjahjana explained the change in manufacturers' operating hours was necessary to ensure a more even distribution of electricity consumption, thus avoiding a supply deficit.

Expected power shortages due to the temporary disruption of gas supplies to two power plants in Jakarta meant two weeks of blackouts were scheduled to begin this week for areas of Jakarta and Tangerang.

Tangerang, one of the capital's satellite cities, is an industrial zone for more than 655 manufacturing firms.

"There are idle capacities of between around 1,000 megawatts and 1,500 MW on the weekend, so industries should shift two working days every month to Saturday and Sunday," Agus said.

Manufacturing companies that operate 24 hours a day will be exempt from the regulation.

He said the government would authorize local governments to oversee the rescheduling of operating hours, under the guidance of state electricity company PT PLN.

"Mayors or regents will decide which operating hours of which companies will be moved to Saturday or Sunday based on the criteria of electricity usage," Agus said.

The government had earlier said companies that moved their operating hours in accordance with the decree would be rewarded.

But PLN president director Fahmi Mochtar said PLN would not give any incentives, as companies already enjoyed electricity subsidies.

Companies now pay Rp 600 per kilowatt per hour instead of the Rp 1,300 per Kwh that would be required without subsidies.

"With that they have enjoyed incentives from the government. So I think there will be no other kind of incentive," Fahmi said.

Companies that refuse to comply with the regulation will receive warning letters and eventually a temporary cut of electricity supply, he said.

The details of the punishments will be prepared separately by PLN after consulting with business associations, in particular the Indonesian Chamber of Commerce and Industry.

The Energy and Mineral Resources Minister Purnomo Yusgiantoro said the decree was a temporary solution for the country's electricity problem until the 10,000 MW power plant project was completed in 2010.

Local governments will evaluate the decree and report on it to the Industry Ministry, the Energy and Mineral Resources Ministry, the Manpower and Transmigration Ministry, the Home Ministry and the State Ministry for State Enterprises.