An increase in power bills this month could happen due to lack of supply but there are ''market intervention measures'' so the public will not feel this, a spokesman of the Department of Energy (DOE) said.

''Power rates may go up because of lack of supply but there are market intervention measures so this will not increase too much,'' Energy Undersecretary Felix William Fuentebella told dzBB.

For example, he said prices in the wholesale spot market can go back to the original after five days as a corrective measure.

To find out what happened, Fuentebella said the DOE will examine the electricity bill for June.

The Luzon grid went on red alert from Monday to Wednesday after several power plants shut down. It was lifted Wednesday afternoon after a power plant went on stream.

Fuentebella said there were no outages in April until late May when outages began.

''That is why we were surprised when these (outages) happened,'' said Fuentebella. He pointed out that Energy Secretary Alfonso Cusi was wondering where the reserves went.

Fuentebella said power situation is expected to be stable this weekend due to lack of demand but it is another story on Monday.

''This weekend, the demand (for power) is not that great. But on Monday, it is different,'' he said.

But on Monday, Fuentebella said it is a different story as reserves remain thin.

He likened the power supply situation to a basketball game. ''It won't be a rout but it will be a close fight,'' he said. DMS