Introduction
Indonesia has a very high dependence on coal as a source main energy for power generation. According to the Energy Institute (2023), coal contributes up to 50% of the total energy mix in Indonesia, with consumption increasing every year the year. Burning coal produces significant carbon dioxide (CO2) emissions, which has a negative impact on the environment. Data from the Global Carbon Budget (2023) shows increase in CO2 emissions from 605.98 million tonnes in 2020 to 728.88 million tonnes in 2020 2022.
Co-firing as a Solution
One solution that can be used to reduce coal use is by co-firing. Co-firing biomass is the process of mixing biomass with rock coals for use as fuel in power plants. This process offers several advantages. First, co-firing can reduce CO2 emissions significantly because Biomass is considered a carbon neutral energy source. Second, this method makes it possible Utilization of agricultural waste that should be waste, becomes a source of energy valuable.
Why Biomass?
In an effort to reduce the use of coal, biomass has emerged as an alternative which are interesting. Biomass is an organic material that can be used as an energy source renewable. One potential form of biomass is rice husks, agricultural waste abundant in Indonesia. With rice production reaching 53.63 million tons in 2022, waste The husk produced reaches 10.73 million tons per year. Rice husks have high calorific value quite high, namely 17.43 MJ/Kg, although it is still lower than coal reached 26.79 MJ/Kg.
Innovation through Torrefaction and Additives
To increase the calorific value of rice husks, pretreatment is carried out using torrefaction method. Torrefaction is the process of heating biomass at relatively low temperatures conditions of minimal oxygen. Research shows that torrefaction at 310°C for 30 minutes can increase the calorific value of rice husks from 17.43 MJ/Kg to 18.6 MJ/Kg. However, this increase is still not sufficient to match coal. The innovation offered is the modification of biochar torrefaction with additives such as glycerol, sunflower seed oil, and used cooking oil. The addition of this additive is purposeful to increase the calorific value of biochar. For example, adding 5% glycerol can increasing the calorific value from 15.7 MJ/kg to 16.35 MJ/kg, and adding 12% oil sunflower seeds can increase the calorific value from 17.9 MJ/kg to 20.4 MJ/kg. Closing Development of a coal co-firing method with modified torrefaction biochar using additives is an innovative step to reduce dependence on stone coal and increasing the use of renewable energy. With an increase in the calorific value of biomass rice husks, it is hoped that this method can be an effective and sustainable solution for Indonesia’s energy future is cleaner and more environmentally friendly