Investigating the Impact of Carbon Tax to Power Generation in Java-Bali System by Applying Optimization Technique
Java-Bali power system dominates the national installed capacity and will contribute to about 76% of the national CO2 emissions from the electricity sector in the future. Thus, minimizing CO2 emission from the Java-Bali system can help Indonesia to reduce the national CO2 emissions level. We apply optimization approach to investigate this problem by including carbon tax into the cost function. We analyzed data based on electricity generating system in 2008. In general the optimization showed that diesel and gas turbine is not needed in the power plant system. Further, the simulation showed that if Indonesia adopted carbon tax by US$56/ton CO2 - USD 86/tCO2; it will lead to three major changing. First, carbon tax will increase the cost of power plant or equivalently increase tax revenue to about 2.1% of GDP in a year. Second, combine cycle has important role to offset decreasing output in steam power plant. Finally, by implementing carbon tax, daily CO2 can decrease by 77,586 ton per day. By applying sensitivity analysis, we also found a structural break in marginal cost when carbon tax is higher than US$ 50/tCO2. There are some weaknesses from this study such as not use strong assumption for availability factor and generating costs. This study proposed that government needs to optimize utilization of combine cycle power plan to offset steam power and implement carbon tax above US$ 50/ ton CO2, to reduce CO2 emissions significantly.
Supply- and demand-side effects of carbon tax in the Indonesian power sector : an integrated resource planning analysis
This study examines the implications of carbon tax for power sector development, demand-side management programs and environmental emissions in the case of Indonesia from a long-term integrated resource planning perspective. Introduction of carbon tax is found to result in improvements of system load factor, system reliability and overall efficiency of thermal power generation while the capacity utilization factor deteriorated. At low tax rates, CO2 mitigation due to changes in electricity price is found to be higher than that due to technological substitution and fuel switching while the opposite was the case at medium and high tax rates. It is also found that tax revenue need not always increase with carbon tax.
Studies on root enamel (2). Enamel pearls. A review of their morphology, localization, nomenclature, occurrence, classification, histogenesis and incidence.
Enamel pearls are one of a number of different enamel structures that can be found on the roots of deciduous and permanent teeth. They have a distinct predilection for the furcation areas of molar teeth, particularly the maxillary third and second molars. They can consist primarily of enamel, but in most instances, a core of dentin is contained within them. On rare occasions, even pulpal tissues can be found. Enamel pearls usually occur singularly, but up to 4 enamel pearls have been observed on the same tooth. Depending on the study, enamel pearls on permanent molar teeth have an incidence rate of between 1.1%-9.7% with distinct differences among racial and national groups. The incidence of enamel pearls increases greatly in histological studies, suggesting that they are often obscured by a covering of cementum.