PRE-FEASIBILITY ANALYSIS OF A WIND-SOLAR-DIESEL ELECTRICITY GENERATION SYSTEM FOR A REMOTE ISLAND COMMUNITY IN THE GULF OF GUAYAQUIL IN ECUADOR

摘要

Reliable energy provision to poor island communities is a challenging problem, particularly in developing countries. This paper presents a pre-feasibility analysis of a wind-solar-diesel electricity generation system to satisfy residential demand in a small, poor island community located in the Gulf of Guayaquil in Ecuador, using HOMER as an analysis tool. The community currently has unreliable diesel generated electricity that energizes homes and street lights, but wishes to replace it with renewable sources as they see that these sources are more aligned with their intention to move into sustainable tourism as a source of income. Relevant meteorological data is lacking and there is only anecdotal evidence that wind is strong in summer time nights at the site. Data for solar irradiance and wind speed were taken from a meteorological station located in Guayaquil, a city relatively close to the island. Wind speed was estimated during a field visit. The community is composed of 85 households for a total of 650 people. Domestic demand data was available and categorized into two types of households. HOMER was used to model four generation system types combining wind turbines, PV panels and Diesel generators to satisfy five different demand models with varying proportions of total households of each type. Selection of the best system is based in both energy and cost optimization, with low use of diesel and low excess of electricity. A sensitivity analysis of the wind and solar resources is included to account for the unavailability of reliable data for wind speed and solar irradiance. The expansion of the system due to population and ensuing demand growth is considered in the analysis using a 25 years project lifetime. The results show that there is potential to install a wind-solar-diesel system under medium-high weather conditions (more than 4 kWh/m~(2)d for solar irradiance and 3.5m/s for wind speed). As a sample, at a 4.5kWh/m~(2)d solar irradiance and 4.6m/s wind speed, a wind-solar-diesel system presents a total NPV of dollar1,616,615 and a LCOE of dollar0.23 per kWh, with a diesel reduction use of 81.8percent and a excess energy percentage of 3.44percent.