Belco customers suffered outages after a glitch during testing at the power plant.

The company said a load shed interrupted power supply as it carried out testing processes on the Battery Energy Storage System.

It did not specify the number of people who lost power, but warned more could be affected over the next few days.

Belco president Dennis Pimentel said: “While every precaution was taken to ensure testing of the BESS did not impact on plant operations, unfortunately a load shed was experienced when the system was being integrated with the grid.

“Testing of the BESS will continue during the next few days and there is a possibility of further load shed events.

“Every effort is being made to minimise the impact on our customers and an update will be provided as soon as testing is complete.”