Hybrid Micro-Grid for Adjuntas, Puerto Rico

Abstract

In the aftermath of Hurricane Maria and other natural disasters, an environmental community organization, Casa Pueblo, in Adjuntas, Puerto Rico decided to increase their social and economic resilience to disasters through grid independent energy resources. This study looks to model different microgrid scenarios where solar power can be complemented with biomass resources and used to power commercial buildings in central Adjuntas. The project involves expansion of the existing 13 kW micro-grid that serves Casa Pueblo’s load. HOMER and HelioScope softwares were used to model energy resources and identify the economically optimum solution, while fostering Casa Pueblo’s goal of energy independence and resilience. Energy consumption for Casa Pueblo and 12 businesses, self-identified as interested, were considered to create a community electricity load. The study modeled four different scenarios. The first scenario modeled a microgrid with only photovoltaic generation. The high solar capacity required would be higher than the possible installation on the existing roofs and storage needs made the costs of Scenario 1 infeasible. Scenarios 2 and 3 included biomass gasification with 1 and 2, 15 kW generators in each model. These two models produced feasible solutions with LCOE below the current cost of electricity in Puerto Rico. Finally, Scenario 4 takes advantage of net energy metering with the Puerto Rico Electric Power Authority (PREPA). This scenario offered a solution with the lowest LCOE and NPC. However, the desire for energy resilience prioritizes grid independence, and therefore Scenario 3 was chosen as optimum, with a NPC of $605,377 over 25 years and an LCOE of $0.16/kWh.