Whether they’re fringed by white sand beaches or secluded among tropical flora and fauna, private islands often offer a serene escape from the bustle of the mainland. But that sense of remoteness may also mean being disconnected from a central power supply. In cases where connecting to the main grid is prohibitively expensive, enterprising island owners have found innovative ways to become self-sufficient for electricity generation.
Some choose to make use of solar, wind and generators to power the resorts and homes that attract vacationers from around the world to their paradise. Others have turned to battery systems and specialized energy management technologies to bring their islands into the 21st century. In the case of Roatan, the Caribbean island famed for its sun-kissed beaches and cruise ship ports, the local electricity utility RECO has opted for a smart storage solution combined with renewables.
The key to Roatan’s new system is GEMS, a component neutral technology that enables the seamless optimisation of all of the energy resources on the island. In combination with the existing 10MW of batteries and the newly built south solar park, GEMS will enable RECO to create a fully integrated electricity generation portfolio that will ensure reliable service even as demand for power spikes during peak holiday season.
In addition to a battery-based power generation system, Roatan’s system is equipped with propane engines that will step in as needed. In cases where no renewable energy is available, or when the electricity system needs to be restarted due to a fault or maintenance, the engines will take over and provide the required amount of power.
On islands, as well as in many rural areas around the globe, the availability of renewables is limited by weather conditions. Wind is another alternative energy source for electricity generation, and can be a useful complement to solar power in regions with less sunshine. Depending on the size and type of generator, wind power can provide a good share of an island’s electricity generation, although a back-up source like a generator is necessary in case of severe storms or technical malfunctions.
Especially in northern latitudes, island projects using 100 percent renewable energies are the exception rather than the rule. However, there are several approaches that come very close to the goal of achieving a self-sufficient island power supply.
These include hybrid systems that combine various power sources with a battery, such as the one implemented on the Norwegian island of Samso, and CHP (combined heat and power) plants that generate electricity from biomass or liquefied natural gas. Another possibility is a mobile power plant, or “mini powerplant”, that sails or is towed to the desired location and docks in a harbor. Floating power plants are essentially mini powerplants with onboard regasification facilities, storage tanks and generators, and run on Liquified Natural Gas (LNG). The LNG is stored on carrier vessels that are moored alongside the power plant. Next Kraftwerke is exploring all of these options for island energy systems in the context of our GREIN project.