Detail Abstract

Role of Renewables in the Energy Transition: Techno-economic Studies towards Least-Cost Off-Grid Electrification and a 100% Renewable Energy (RE) System Philippines

Abstract

Archipelagic countries like the Philippines and Indonesia rely on diesel generators to power small off-grid islands. The dependence on diesel for power generation leads to high greenhouse gas emissions, high power generation cost, and unreliable electricity when supply of diesel is difficult (i.e. presence of typhoons), among others. In many of these small off-grid islands, grid interconnection is also impractical due to the long distance from the grid-connected bigger islands. However, there is an opportunity to decarbonize the energy system in off-grid islands by harnessing endemic renewable energy sources, such as solar, wind, and biomass. In this work, we will show that hybrid systems utilizing renewable energy sources offer a cleaner and more sustainable way of powering these off-grid islands, while at the same time, lowering the power generation cost. Using an energy systems simulation tool, which balances both energy and mass, we simulate the hourly operation of the island grids for an entire reference year to find the cost-optimal hybrid configuration from the various combinations of conventional power sources (e.g. diesel plant), renewable energy sources (e.g. solar photovoltaic, wind turbine), and energy storage (e.g. batteries). The techno-economic modelling obtains the cost-optimal system component sizes having the lowest levelized cost of electricity (LCOE) using typical island load demands and using local solar and wind resource data. In 125 out of 143 of the islands considered, the utilization of both solar and wind resources offers the cost-optimal solution. Batteries play a key role in increasing the penetration rate of solar and wind, without further increasing LCOE. Since water access in off-grid islands is also challenging due to limited water resource, the techno-economics of coupling a desalination unit to an island grid as a form of energy storage was investigated.  Lastly, I will present the results of our on-going study of a 100% RE system Philippines, emphasizing that the global energy transition is no longer a question of technical feasibility or economic viability but of political will.