Private islands are often remote, and they need a reliable power supply. They typically use solar energy for electricity, with a back-up power source such as a generator or batteries. This combination has worked well for a number of well known island destinations such as Little Hall’s Pond Cay, owned by Johnny Depp and Nukabati Resort in Fiji. However, the costs and complexity of running an entirely renewable energy system have been a barrier for many.
But now there is a solution that enables even the most cost-conscious island owner to take advantage of solar, wind and battery power without paying through the nose. It is called GEMS, and it’s the brainchild of a German company named DHYBRID, which specialises in designing total energy systems for remote areas.
The basic idea is simple enough: solar panels generate electricity by converting sunlight into electric current, which charges batteries which in turn power appliances when the sun isn’t shining. When there is insufficient sunlight, a backup power source such as a diesel engine takes over. When the batteries are exhausted, a new charge is pumped in and the cycle begins again.
To make the most of the sun’s energy, the system uses a battery management system (BMS) that constantly monitors how much power is being generated and consumed by each process on the island, down to individual LED fixtures. The BMS then balances the load by directing the appropriate amount of electricity to each of the energy sources, ensuring that a steady flow of power is maintained.
Kamen is confident that the new system can handle the island’s energy needs now, and will continue to do so for the foreseeable future. But he is also looking forward to implementing more renewables as the economy improves and he can afford them.
Until recently, Roatan’s islanders got their electricity through the state-owned public utility, PREPA, which has been saddled with massive debt. But a recent agreement with bondholders to cut costs may bring a turnaround. Regardless, PREPA will need to do more than slash its costs to remain viable in the long run. It must also modernise its generation capacity.
The DHYBRID system uses one megawatt-hour of storage in supercapacitors from New York-based Kilowatt Labs, a power management company. These electronic devices hold and release energy much more quickly than batteries but don’t degrade as they do.
The system also uses a series of inverters to continually monitor the state of the batteries, and when they fall below 50%, the inverters signal for the standby diesel generators to start. They dispense the energy needed until the batteries are fully charged, at which point the inverters tell the generators to stop. As a result, the DHYBRID system allows RECO to seamlessly integrate any further renewables as it moves towards 100 percent renewable energy.