The technology group Wärtsilä will supply two 10-megawatt/ 10-megawatt hour energy storage systems under an Engineering, Procurement, and Construction contract to Caribbean Utilities Company  in the Cayman Islands. This project, which will be CUC’s first energy storage facilities, will enable the utility to approximately double its renewable energy capacity on Grand Cayman, the largest of the three Cayman Islands. The order was booked to Wärtsilä’s order intake in Q3 2022.

The new energy storage facilities will allow CUC to operate its generating assets in a more efficient manner reducing fuel costs to electricity consumers. Additionally, the energy storage systems will facilitate up to a total of approximately 29 MW of distributed customer-sited renewable energy resources without causing instability to the grid. Like many island grids, Grand Cayman’s power system is isolated from grid-tied electricity, and susceptible to unplanned changes in generation output. Until now, the network connected electricity generation sources on Grand Cayman comprised 161 MW of diesel fuelled generation and approximately 14 MW of solar photovoltaic (PV) generation.

The energy storage systems will be connected to the Hydesville, West Bay and Prospect substations, which will provide extensive power system optimisation capabilities – from spinning reserve capacity to improved frequency response, and to enhanced grid stability, while also saving CUC on fuel costs. Each facility will include Wärtsilä’s GridSolv Quantum, a fully integrated, modular and compact energy storage system, as well as the GEMS Digital Energy Platform, Wärtsilä’s sophisticated energy management system.

Islands like Grand Cayman in the Caribbean demonstrate the importance of energy independence at the forefront of addressing climate change. Based on work with other microgrids around the world, Wärtsilä has gained insight on how to enable clean, optimised power systems that provide industry-leading energy and environmental benefits, improved control capabilities, and increased revenues.

“We are pleased to work with Wärtsilä to establish our first energy storage systems. This represents a crucial step for CUC to integrate more renewable energy into the grid. Once this project is completed, we anticipate savings on fuel costs and improved reliability of services for our customers on Grand Cayman,” said Sacha Tibbetts, Vice President, Customer Services & Technology, Caribbean Utilities Company.

“Energy storage has proven to be a game changer for our numerous island-based customers in the Caribbean and beyond to simultaneously lower energy costs, reduce greenhouse gas emissions, increase renewable energy consumption, and improve grid reliability,” said Jon Rodriguez, Director, Engine power plants, Wärtsilä Energy in North America. “Our industry-leading solutions empower islanded grid operators to optimise and modernise their energy systems, and we are happy to assist CUC along this path.”

The GEMS platform will provide several advantages to islanded systems which have until now been rare for even big grids. These include amongst other things: short term overload capacity, voltage support, black starts and peak shaving. As such, this project will showcase the full capabilities of GEMS.

Caribbean Utilities Company is a privately owned electricity generation, transmission and distribution utility which owns an installed generating capacity of 161 MW. It is the only electric utility in Grand Cayman, the largest island of the Cayman Islands, with a population of approximately 65,000 mostly residing in Grand Cayman.

The Wärtsilä energy storage systems in Grand Cayman are expected to become operational in mid-2023.