Solar PV mini-grids for Small Islands
Solar photovoltaic (PV) powered mini-grid systems have been under consideration for use in the Pacific Island countries for some time. Until recently, however, such systems were deemed to have limited potential. With recent improvement in inverter technology and increase in household demand for electricity in many small islands, the mini-grid approach may now be both technically and economically feasible. The installation of a PV mini-grid system on the island of Apolima, Samoa in November 2006 has been a milestone achievement and could potentially be replicated on small islands across the world.
Apolima Island is a small island in Samoa consisting of a volcanic caldera approximately 4km in diameter. It lies between the main islands of Upolu and Savaii, about 45 minutes boat ride from Upolu. The island features high, steep cliffs that allow access at only one point. The only village in Apolima is located inside the caldera near a point that opens to a constricted and difficult passage from the sea. The village has a population of approximately 100 people. Soil quality is poor and therefore coconuts and fish are the islanders’ main sources of food. The Samoa Electric Power Corporation (EPC) used to operate a small diesel generator during hours of peak energy demand.
The electricity supply faced a number of problems including the lack of 24-hour supply, noise emissions, inefficient operations with a high level of technical and non-technical losses, environmental pollution by waste oil and fuel, difficulties in providing an operator/technician to maintain the generator and transportation of diesel fuel. In order to address these problems, EPC in cooperation with the Government of Samoa and UNDP launched a solar PV mini-grid system along with a stand alone system for a church. Both systems were designed to be replicated in other parts of Samoa. The expected overall outcome was to improve livelihoods through a reliable, effective and environmentally friendly power supply 24 hours a day.