We will install a hybrid solar – wind system The generated power will feed the islands electrical load directly and charge an array of batteries designed for off-grid power usage and sufficient to provide power for all essential functions on the island. We can minimize use of the batteries and extend their longevity by running certain devices such as pumps for topping of water tanks at times when we are also producing power, i.e. when there is sun and/or wind. The batteries will provide most power at night when there is little wind or when we have a stretch of cloudy, windless days.
The solar array will include 10-12 panels producing around 2000 watts (2 Kw) at peak production. The wind turbine will be modestly sized to minimize it’s visual footprint and noise. This link shows a model which would be suitable for our needs: http://www.windenergy.com/products/whisper/whisper-200
While most components are available in Nicaragua, we may import some elements such as the solar panels to minimize high costs resulting from import duty.
Most items consuming power on the island including lights, fans, water pumps, and refrigeration will use direct current (DC) supplied directly from the production/storage systems without needing conversion to alternating current (AC). Choosing devices carefully will provide great efficiency, avoid the approximate 5-10% loss in conversion from DC to AC, and costs associated with purchasing and maintaining large inverters required for conversion. Small inverters (convert DC to AC) in guest spaces and the kitchen will provide for guests needing to plug in and the few necessary devices for which there is no DC option such as a blender.
Besides lights, fans, and pumps, we will also provide power for a modest music system, security cameras, and computers for managers. Laundry will be send off the island due to higher power requirements associated with washing linens.