GEA battery testing triggers power cut

Much of Gibraltar was plunged into darkness in the early hours of this morning, as the Gibraltar Electricity Authority carried out testing on its new Battery Storage system.

The Government says the BESS system will make future power cuts less likely as the batteries will allow for energy to be stored for back-up use when needed.

Speaking to GBC earlier today, GEA CEO Stanley Antoniou said the system didn’t respond as expected causing the outage but that teams were quickly dispatched and supply restored promptly

The Battery Energy Storage System at the North Mole is the result of a £16.5 million deal signed by the Government in 2024. 

The system aims to provide instant back-up power in the event of engine failure and help stabilise the electricity grid by supporting frequency and load variations.

Its introduction is another step by the Government to stop power cuts affecting the Rock.

A seven hour Gibraltar-wide black out back in September led to Parliament unanimously passing a bill giving the Electricity Authority the power to issue fines of up to £100,000 to contractors whose actions lead to power failure or disruption.

Last night’s power cut though, was due to testing the Battery Storage - which did not perform as expected. The GEA's CEO Stanley Antoniou told GBC that further testing is planned as they work to integrate the new system.

The Authority says it would like to apologise to its customers for any inconvenience caused.

Full statement from the GEA:

The Gibraltar Electricity Authority has been working closely with Battery Energy Storage System (BESS) contractors to optimise and program the integration of the BESS into the GEA network.

As part of this process, a series of controlled live tests have been conducted, including simulations of engine failures at low load levels during late-night and early- morning hours. These tests are designed to ensure that system parameters remain within established standards under varying operating conditions.

During testing last night, previous results at levels up to 6MW had remained within acceptable frequency ranges. At approximately 12:20 a.m., a simulated engine failure was initiated at a 4MW load. This resulted in a frequency drop that activated the system’s falling frequency protection, leading to the loss of two feeders. Service was quickly restored after system parameters were reviewed and adjustments were made to BESS controls and instrumentation.

Testing then resumed, progressing from 4MW to 6MW and subsequently to 7MW, with BESS performance remaining within acceptable limits. Upon increasing the test to 8MW, the BESS did not respond as expected, resulting in a frequency decline below network thresholds and causing a system-wide outage. Our teams were quickly dispatched to the affected areas and restored supply promptly.

BESS contractors are actively investigating the incident to determine the cause of the failure and to implement corrective measures to prevent a recurrence.

The GEA would like to apologise to its customers for the inconvenience cause during testing of BESS.