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Indonesia, as a developing country with an ever-increasing population, has an increasing amount of municipal solid waste, most of which is organic. Organic waste with high, medium, and low moisture content was acquired from TPST Piyungan, Yogyakarta. Moisture content is a organic waste quality parameter that must be studied for its impact on the gasification process. Gasification produces products in the form of gas (producer gas), solid (char+ash), and liquid (heavy tar+light tar). The light tar is the most difficult to separate. The light tar component has a high moisture content and contains 1-6 ring aromatic carbon 46.91%, heterocyclic 42.61%, phenolic 1.68%, benzene 0.60%, and other 8.20%. Meanwhile, 52.05% of the medium is aromatic carbon rings 1-6, 39.02% is heterocyclic, 0.44% is phenolic, 0.63% is benzene, and 7.86% is other. The content of 1-6 rings at low moisture content is 39.00% aromatic carbon, 46.60% heterocyclic, 1.20% phenolic, and 13.20% others. Producer gas has a high moisture content for chemicals that contribute to calorific value: CO 49.27%, H2 2.49%, and CH4 4.23%. CO is 50.37%, H2 is 2.41%, and CH4 is 4.40% with medium moisture level; at low moisture content, CO is 53.82%, H2 is 2.55%, and CH4 is 4.70%. Light tar and producer gas are crucial products for determining the quality of the gasification process based on the quality of the organic waste. It is critical to determine the magnitude of the influence on the energy conversion equipment for waste power generation. [ABSTRACT FROM AUTHOR]

Biodiesel is one of promising alternative fuel to be implemented in Indonesia due to its abundant resources. One of issue for utilization of high ratio blends was high fuel consumption of biodiesel as it has lower heating value compared with diesel fuel. Our previous study reported that light duty vehicle fueled with 30% biodiesel (B30) had result on increase of fuel consumption at around 2 – 3%. In study, we discussed for an influence of B30 on advance heavy duty engine application. Heavy duty engine has obviously difference range of operation with light duty engine therefore it might also influence to fuel consumption. Here, we investigated an effect of B30 on heavy duty fuel consumption at various engine speed and load by referring to R49 international standard. An experiment result showed that utilization of B30 on heavy duty engine at various load and engine speed has resulted on an increase of mass fuel rate at an average of 2%. Further, the results also showed that the highest difference of fuel consumption for B30 and diesel fuel occurred at low engine speed with 75% load conditions. [ABSTRACT FROM AUTHOR]

The increase in the price of petroleum-based fuel due to increasing demand and exacerbated by the war has made various countries start competing in managing available alternative energy, including bio-based fuels. Bio-based alternative fuels are also helpful in the transition to net zero emissions by 2050. Indonesia has successfully implemented B30 in the land transportation sector without significant problems. In the future, Indonesia plans to implement B40 or more; this is a challenge that is not easy, especially in the marine sector, with different distribution patterns, storage, operation, and engine characteristics, which pose a significant risk to the reliability of ship operations and increased maintenance costs. This research is directed to determine the level of fuel degradation in ships. With the advanced technology of the ship's engine, the water content specification is 200 ppm, and ISO cleanliness is 18/17/14. This specification is generally applied to engines with EU stage 2/Tier 2 specifications. As for higher technology, some engine manufacturers refer to WWFC with a maximum ISO cleanliness of 18/16/13. The fuel parameters that focus on this research are ISO cleanliness, water content, TAN, bacteria growth, and metal content. B30 samples taken from marine showed TAN and water content test results of around 27% and 65% below the national standard. Bacterial growth <10 CFU/ml, levels of some metal content in the range of less than or equal to 1 ppm. Particle count r>4 microns around 1300%, r>6 around 400-500%, and r>14 around 60-100%, all % above the limit based on WWFC 2019. High particle content can cause faster filter clogging and potentially damage the engine if the abrasive material enters the engine. The contaminant characterization data carried out in this study are beneficial as reference data in optimizing and selecting a suitable filtration system more appropriate. [ABSTRACT FROM AUTHOR]

This article examines the issue of load imbalance in electric power distribution systems, which leads to current flow in the neutral conductor of transformers. The study aims to investigate the impact of load imbalance on neutral current and losses in the transformer. The analysis reveals that a load imbalance of 24% during the day results in a large neutral current of 109 A and increased losses due to neutral current flowing to the ground (8.47%). The findings highlight the significance of load balancing in reducing losses and improving the efficiency of electric power distribution systems. The study provides insights for researchers and practitioners to develop strategies for load balancing to mitigate the effects of load imbalance on transformer losses. [ABSTRACT FROM AUTHOR]