Home » Case Studies » Saft energy storage in Bermuda nets $1 million in fuel savings within months
As part of a long-term plan to improve power plant efficiency, the Bermuda Electric Light Company (BELCO) commissioned Saft to deliver and install a turnkey battery energy storage system (ESS). The system provides 10 MW steady state power for spinning reserves and frequency response to maintain grid stability and up to 15 MW for the first minute if required.
One of BELCO’s single most significant operating expenses is fuel for its generators. Like many island communities, imported fuel is very costly compared to the North American mainland and sudden changes of frequency can cause up to ten loadshedding events per year.
The operator had two objectives for the project. The first was to reduce fuel costs by using the ESS to provide spinning reserves, estimating that an ESS could save 2% of OPEX costs by reducing the number of running diesel generators and allowing the remaining units to run at optimal load. The second objective was to provide ultra-fast frequency response to support power quality, maintain grid stability and avoid load shedding events. Additional ESS benefits include enabling more units on light fuel oil (LFO) to be switched to units operating on heavy fuel oil (HFO), which is around 18% cheaper and contains 6% more energy, and reduced diesel maintenance.
Protecting Bermuda from load shedding
The energy storage system is ready to respond to sudden changes on the network. So, when a genset producing 10 MW tripped, the ESS immediately kicked in and prevented the frequency dropping below the load shed point of 58.2 Hz. A similar trip before installation of the ESS would have resulted in load-shedding and loss of supply to customers.
Not only has the Saft ESS been extremely beneficial in preventing under-frequency load shedding, but the experience gained with this technology is invaluable. Utility-scale battery systems are an indispensable asset to cope with the ever-changing grid. We’ve been delighted with the ESS so far.Stephanie Simons BELCO BESS Project Manager
Saft ESS and power conversion package