Developing a Green Path Power Expansion Plan in Indonesia by Applying a Multiobjective Optimization Modeling Technique

AbstractThis paper aims to apply a multiobjective optimization modeling technique to a power expansion problem evaluating two objectives functions: minimizing the power generating cost and minimizing CO2 emissions, between which there is a tradeoff. A convex curve is obtained representing the relationship between the generating cost (Rp/kWh) and CO2 emissions (ton). This represents a bad-luck curve where there is an increasing marginal cost to reduce 1 t of CO2 emissions. This is because most of the less-carbon-intensive power plants consume oil, which has the highest fuel cost. Instead of simply minimizing CO2 emissions, this paper argues that Indonesia needs to pursue technology to switch from steam coal subcritical technology to supercritical and ultra-supercritical technology to reduce CO2 emissions. It is further found that the generating cost will increase by less than 1.6% and yearly CO2 emissions can be reduced by about 6.9% by adopting supercritical technology. This implies that adopting ultra-supercritical technology can cut CO2 emissions by more than half. A squeezing effect is also found by adopting more-advanced steam coal technology. Thus, promoting renewable energy and gas utilization also should be enhanced. The green path power system allows both CO2 emissions and the generating cost to increase gradually, but with lower CO2 emissions than by minimizing the generating cost alone. It is thereby proposed that the current feed-in tariff for renewable energy also needs to be supported with an emissions reduction target.