Are High Renewable Energy Shares In Large Power Grids In Indonesia Too Expensive?

Abstract

High shares of power from renewable resources in large power supply grids do not imply insurmountable technical problem anymore. A question is rather whether, besides the technical feasibility, it is also economically viable to go for a high share of power from sun, wind, water, geothermal resources and biomass. This paper scrutinizes the costs of a renewable-energy based power supply in the Java-Bali grid, by far the largest grid in Indonesia. The study refers to a challenging power supply scenario in which 100% of the power in the Java-Bali grid comes from renewable resources. This scenario is expressed in a one-year modeling of the load and the respective power supply in the grid. The modeling identifies possible sets of installed capacities of the different power plant types and storage systems that allow the supply of the required electricity. A cost scenario is applied to these sets, which renders the system costs, and finally the power generation costs. All scenarios refer to the year 2050. The results show that, assuming moderate financing costs, the cost of the electricity generation in the possible supply systems would not be higher than that in currently existing systems in developed countries; and it would even not be far away from the power generation cost in the current Java-Bali grid. A secondary result of the study is that the usage of special long-term storage systems for the balancing of seasonal power supply fluctuations, additionally to pumped storages and batteries, is not economically necessary in the considered grid.