Environmental radioactivity analysis has been carried out to determine the level of environmental radioactivity and the potential radiological hazards at Tanjung Enim’s coal mine. Gamma spectroscopy method has been carried out to identify radionuclides and their types of activity. The results of radionuclide concentration are used to determine the radiological hazard index and become input data for the Residual Radioactivity Onsite 7.2 application to determine the dose rate and long-term cancer potential received by workers in coal mines. The results obtained for the average concentration of radionuclide activity in coal samples are 226Ra, 232Th, and 40K are 72.468 Bq/kg, 86.905 Bq/kg, and 1802.049 Bq/kg, respectively. While the soil samples 226Ra, 232Th, and 40K respectively 79.205 Bq/kg, 100.209 Bq/kg, and 1443.275 Bq/kg. The radionuclide concentrations of both samples exceeded the UNSCEAR and worldwide reported averages for coal and soil. The average radiological hazard index for coal samples, namely Raeq, Hin, and Hex, was 335.500 Bq/kg, 1.102, 0.906, respectively. While the soil samples were 333.636 Bq/kg, 1.115, and 0.901, respectively. The index parameter is already lower than the UNSCEAR recommendation except for Hin, so there is a potential radiological hazard in internal pathways such as respiratory and digestive organs for mining workers. The total annual effective dose rate based on 5 RESRAD-Onsite 7.2 pathways, namely external gamma, inhalation, radon, soil ingestion, and drinking water, is 1.675 mSv/year, exceeding the dose limits determined by ICRP, 1 mSv/year. The ELCR is 6.625×10-3 which exceeds the UNSCEAR recommendation, 2.4×10-4. Based on the results, it is necessary to intervene in the mining environment of the Tanjung Enim’s coal mine.

The current government's goal is the realization of an even distribution of the electrification ratio in Indonesia. However, in 2018 the electrification ratio in Nusa Tenggara Timur (NTT) only reached 62.07%. One of the solutions offered is the implementation of a Bladeless Wind Turbine (BWT). BWT is a type of wind power plant that can work optimally in areas with low wind speeds, 3 to 8 m/s, which is still above the NTT average wind speed, 2.3 m/s. This study aims to optimize the mechanical design of BWT with shape and size parameters based on the manipulation of the coefficient of friction through computational fluid dynamic simulations that can work optimally according to wind speed in NTT. In this study, 3 design variations were used, namely Initial Design, Modified Design 1, and Modified Design 2. Based on the research that has been done, MD2 has better results than MD1 and ID, and it can be said that MD2 can work optimally in wind speed areas. low. So MD2 is a mechanical design model that is very suitable to be applied in NTT and is expected to be a recommendation in making masts for BWT-based wind power plants in Indonesia.

The current government's goal is the realization of an even distribution of the electrification ratio in Indonesia. However, in 2018 the electrification ratio in Nusa Tenggara Timur (NTT) only reached 62.07%. One of the solutions offered is the implementation of a Bladeless Wind Turbine (BWT). BWT is a type of wind power plant that can work optimally in areas with low wind speeds, 3 to 8 m/s, which is still above the NTT average wind speed, 2.3 m/s. This study aims to optimize the mechanical design of BWT with shape and size parameters based on the manipulation of the coefficient of friction through computational fluid dynamic simulations that can work optimally according to wind speed in NTT. In this study, 3 design variations were used, namely Initial Design, Modified Design 1, and Modified Design 2. Based on the research that has been done, MD2 has better results than MD1 and ID, and it can be said that MD2 can work optimally in wind speed areas. low. So MD2 is a mechanical design model that is very suitable to be applied in NTT and is expected to be a recommendation in making masts for BWT-based wind power plants in Indonesia.