The increase has been attributed to Napocor making full use of the Ilijan gas-fired power plant in Batangas. From January to June 2003, the company has generated up to 2,448 GW/h. Last year, it only generated - during the same period - output was only 652.27 GW/h.

The use of natural gas is part of the company's plans to reduce the Philippines dependence on fuel oil to power the country's power plants. Other sources of energy that are being utilised in lieu of oil are hydropower and geothermal energy.

However, the an internal company report has revealed that coal-fired power plants represent Napocor's largest source of power generation, with 32.37% of the company's total power output - from January to June - coming from these plants.