This paper looks at ways for Indonesia to switch from fossil fuels to renewable energy sources for electricity, aiming to lower carbon emissions while meeting energy needs. By using computer models, the researchers planned a gradual swap of old fossil fuel plants with new renewable ones. Their results suggest that Indonesia could reach nearly zero carbon emissions in electricity by 2050 without extra costs, possibly saving money. They tested faster transitions and found that slashing emissions to zero by 2040 and even 2030 could be doable, with lower costs mainly due to cheaper renewables. The study also suggests expanding electricity production with renewables and introducing mini-power systems for remote areas as budget-friendly alternatives to expanding the main grid.