Plans have been filed with the Development and Planning Commission for a battery energy storage station [BESS] at the North Mole power station that will provide resilience to Gibraltar’s electricity supply and reduce the Rock’s carbon footprint.
The BESS is a zero-emission alternative to existing temporary diesel generators that provide grid support and stability services.
It will act as a large uninterruptable power source – much the same as many offices have on a far smaller scale – capable of providing an hour of Gibraltar-wide electricity supply in the event of a power cut.
That would provide a sufficient buffer on most occasions to enable engineers to get the system back up and running without the consumer noticing any glitch in supply.
The BESS’ capacity will be 14 megawatts for one hour, approximately the size of one of the power station’s engines.
“In power engineering terms, it’s an eternity, and would mean…that if we lose an engine, this kicks in, none of our consumers finds out about it, and we’ll have plenty of time to start another engine and basically take over from the [BESS] and keep it in reserve again,” Mr Caetano said during a recent interview on GBC’s Gibraltar Today.
Another benefit of the BESS is that it will reduce emissions created by the current back-up system of temporary diesel generators, some of which are kept “turning over” to ensure they can be used rapidly if needed.
“The existing generators produce heavily polluting emissions, which will cease with their replacement by the BESS, saving an estimated monthly average of 400 tonnes,” a planning statement accompanying the application said.
“There is also a high monthly cost associated with the current generators, both in rental and fuel costs, which will be reduced by about 70% through the installation of the BESS.”
Once through the DPC approval process, the decommissioning of the existing temporary generators and the installation of the BESS will occur in stages.
Energyst, the owners of the existing generators, are responsible for ‘leaving the site in the same or better condition as it was on the delivery date’, when the existing generators were installed.
The existing temporary generators will be removed by Energyst in batches.
The southern segment of generators will be removed first and replaced by the BESS, while the generators in the northern segment remain in-situ.
This northern segment will then remain vacant for use as hard standing, with any future proposals for this area subject to a separate, future planning application.
Once the BESS is successfully implemented and its reliability tested, the remaining generators, fuel containers and fuel processing facilities will be removed.
The specification for the existing temporary generators contains 110% spill containment of onboard engine fluids, reducing the likelihood of any contamination during the decommissioning process.
The installation of the BESS will take approximately six months and the hope is to deliver equipment and materials by sea if possible, although plans have also been drawn up for delivery by road if need be.
That latter option would entail a maximum of 20 lorries making deliveries over the six-month construction period.
The proposed development has an estimated design life of at least 15 years for the batteries, and 25 to 30 years for all other ancillary infrastructure.
It will be designed such that all relevant environmental consents and regulations are met during the operational phase, the planning statement said.
The proposed BESS is not anticipated to result in any significant potential adverse environmental effects either through installation or during its operational life.
“Several features of the BESS proposals provide environmental betterment over the existing temporary diesel generators on this site, and these include a more sustainable energy offer, much reduced air emissions, the use of natural resources, and a significant reduction in noise pollution,” the application stated.
The BESS project was first revealed by the then Minister for Utilities, Albert Isola, in an interview with this newspaper in 2022.
At the time, Mr Isola said that one of the challenges facing Gibraltar is that its geographical and political circumstances mean it has to be entirely self-sufficient in the generation of electrical power.
“If you think of the UK or anywhere else, any village in the UK has a number of different suppliers of power and if one goes, the other clicks in and you don't even notice, your power continues,” Mr Isola said at the time.
“We don't have that luxury, we have one power station.”
“Whereas they have outages in the UK the whole time, you don't notice. Here you do because we only have one source."
He said installation of the BESS would address that challenge.
“The beauty of that is that it will eliminate the bulk of the power cuts because it will take the slack when a machine trips,” Mr Isola said.
“The battery kicks in and not only does it give us that resilience but it also neutralises the power that we produce."
“For people that have particularly high-tech equipment, they notice that our power goes up and down.”
“By putting that power through a battery, which you do as you’re charging it anyway, it actually gives you a straight line of power which is far better.”
“So it will help us on a number of different fronts.”