Cost optimization for the 100% renewable electricity scenario for the Java-Bali grid

Abstract

A 100% renewable electricity supply is no insurmountable technical problem anymore after the respective technologies to harvest the energy from multiple renewable energy sources have been developed and have reached a high level of maturity. A problem may rather be suspected to reside on the economic side of an exclusively renewable electricity supply. The present study examines the economic implications of a renewable energy scenario for the Java-Bali grid. Based on given energy supply scenarios, the costs of an electricity supply from renewable energy sources alone are determined. Economic optimum configurations are determined for which the annual system costs and accordingly the power generation costs are minimized. First the system running costs are considered, i.e. the operation and maintenance costs as well as the costs of the continuous renovation of system components, while capital costs are not taken into account. After this the capital costs are taken into consideration, and total system costs and power generation costs are determined. One result is a specification of economic optimum system configurations. Another important result is that a future electricity supply from renewable resources alone is not more expensive than the current power generation in developed countries. A further result is that the integration of special long-term storage into the Java-Bali grid, like for instance methane storages, besides pumped storages and batteries, is not economically favorable if further moderate battery cost reductions are reached.