A new PV-diesel-hybrid system combined with a battery storage system makes the island St. Eustatius less dependent from fossil fuels.
The Caribbean island St. Eustatius was given the status of a “special municipality”, a special administrative division of the Netherlands, whose citizens can e.g. vote in Dutch national and European elections. At the same time the special municipalities do not necessarily have the same laws as the Netherlands. The Dutch Ministry of Economics decided to finance the installation of a PV system to make the island and the local Statia Utility Company (STUCO) less dependent on oil-imports.
“We were looking for fossil fuel reduction and at the same time for a solution with both very low maintenance and also stand-alone operation,” said Fred Cuvalay, CEO of STUCO. Overall, St. Eustatius now has a PV plant with a total capacity of 1.9 MW and batteries of the type Sunny Central Storage 1000 with a capacity of 1 MW. The new system can supply 23% of the island’s yearly electricity demand and save up to 30% of the fossil fuels used. The battery storage system and the Fuel Save Controller 2.0 by SMA help in producing nearly a quarter of the 13.5 GWh of electricity, which are used on St. Eustatius per year with the help of the sun.
In times of high solar irradiation the batteries enable the system to reach a solar coverage of 88%. Being able to store excess electricity also helps to stabilize the power grid of the island. This is done by regulating the frequency, limiting weather related power fluctuations of the PV plant and stabilizing the optimization of the diesel generator. As a whole, STUCO expects to save more than 800,000 litres of diesel fuel per year thanks to photovoltaics and batteries.
“Rapid movement of clouds in this region, in particular, leads to extreme fluctuations in solar power generation which constrains the integration of large-scale photovoltaics into diesel-based grids,” commented Volker Wachenfeld, Executive Vice President SMA business unit Off-Grid and Storage. “That's why using large-scale storage systems is meaningful for this application as they minimize the impact of fluctuating energy sources on diesel generators”, he added. The PV plant on St. Eustatius is the first project of this kind in the whole Caribbean area and is seen as a showcase project for the neighbouring islands.
The hybrid system has been installed turnkey ready on St. Eustatius within nine months by the local system integrator Eco Energy N.V., Curaçao. Within the framework of a service contract for the PV system, SMA Sunbelt Energy GmbH also offers a customized PV hybrid monitoring system for integrated data logging of power management system, PV inverters, battery inverter, diesel generators and the complete storage system.
SMA Solar Technology AG / Tanja Peschel