Investigation into the Correlation of Solar Modules within a Subgrid for the Island of Barbados

The dependence of many Small Island Developing States (SIDS), including Barbados, on fossil fuel imports, to meet national energy demands not only contribute to a large portion of foreign expenditure but stands to further increase their vulnerability to climate change impacts. Over the last decade, the Government of Barbados has developed an Energy Policy that outlines the country’s strategy to transition from fossil fuels to renewable sources of energy. Energy production from photovoltaic (PV) systems forms a significant component of this strategy. To date, the private investment has resulted in the erection of a 10 MW PV plant in the north of the island with smaller private sector investments located at industrial facilities across the island. Government investments have funded small PV plants across the island. Homeowners are increasingly installing small roof-mounted systems across the island. In most cases, the PV systems are grid-tied within a buy-all sell-all arrangement. It is anticipated that PV investments will continue into the foreseeable future. While the annual number of sunshine hours in Barbados makes PV generation a good option, the stability of the national grid is a concern given the characteristics of cloudiness across the island - coastal cloud characteristics may differ significantly from inland cloud characteristics. The variability in cloud characteristics will, for example, (i) control the variability in the irradiance reaching ground level and (ii) result in highly correlated production between PV systems in sub-grids. These factors will influence spin-up capacity and its utilization as well as energy storage design. The presentation explores the important role cloud characteristics may play in the design of optimal PV networks for SIDS.