Assesment of hybrid powerplant in Matenggeng DAM

Abstract

Indonesia's electricity production is dominated by non-renewable resources, with coal at 48% and gas at 28%. Indonesia should start changing its energy sources as non-renewable resources over time can damage the environment. One of the abundant renewable resources in Indonesia is hydropower, but the production of electricity by water is highly dependent on the availability of water, which is affected by seasonal variability. Matenggeng Dam is planned to have a Hydroelectric Power Plant (PLTA), which has a discharge capacity of 19 m3/s. By analyzing the operation pattern of the Matenggeng reservoir, it can produce power of about 11.74 MWac (33 GWh/year), which occurs at the normal elevation of ±194 m. Then, when the dry season hits, its power production decreases to 5.74 MWac (19 GWh/year), which occurs at the lowest elevation of the dam, 148 m. This indicates that the power is decreased by 6 MWac (14 GWh/year). Furthermore, solar renewable resources also have great potential in Indonesia, supported by Indonesia's location on the equator and tropical climate, which means that Indonesia will be in the sun all year round. So, in this study, an attempt was made to optimize the decrease in existing electricity production in Matenggeng by hybridization of hydropower with floating solar power plants (PLTS). According to the analysis, the area of the floating solar power plant required is 236x291 m with 132 moorings and 44 anchor blocks on each side of the solar power plant island. Furthermore, the solar power plant has successfully produced 14 GWh of energy annually, where the monthly generation is stable at 1,200 MWh per month. In previous studies, optimization has been carried out with existing spilled water, which is tapped into a pipe that has the same capacity as the hydropower plant. This system produces 78 GWh of electricity per year. The effectiveness of this system is much greater by at least 30% than floating solar power plants. This hybridization system is less effective due to the small amount of electrical energy generated by the solar power plant, which is due to the lack of available land at the lowest water elevation.