Kebutuhan energi di Indonesia terus mengalami peningkatan setiap tahun. Kebutuhan energi tersebut dipenuhi dari energi primer yang berasal dari batu bara, min-yak bumi, gas bumi, serta energi baru terbarukan (EBT) misalnya energi panas bumi, an-gin, panel surya dan sebagainya. Dari empat energi primer tersebut, gas bumi merupakan energi fosil yang ditingkat-kan bauran energinya sampai tahun 2050. Hal ini dikarenakan cadangan gas bumi yang cukup besar, ramah lingkungan dan relatif murah daripada minyak bumi, serta gas bumi untuk pembangkit listrik dan bahan baku industri. Konsumsi gas bumi di Indonesia terus meningkat, sedangkan besar cadangan gas bumi Indonesia semakin berkurang dan masih adanya komitmen ekspor gas bumi selama puluhan tahun ke depan. Mulai tahun 2012, prosentase pemanfaatan gas bumi Indonesia untuk konsumsi domestik mulai lebih besar daripada untuk ekspor. Seiring dengan terus meningkatnya konsumsi domestik tersebut dapat mengakibatkan Indonesia akan menjadi negara net im-porter gas bumi di kemudian hari. Untuk itu, diperlukan upaya prediksi kebutuhan konsumsi gas bumi di masa depan yang akurat sehingga pemerintah dapat mengupayakan pemenuhan pasokan gas bumi tersebut baik dari kegiatan eksplorasi dan eksploitasi dalam negeri maupun membuka opsi impor. Maka proyeksi tersebut dapat dibantu menggunakan Artificial Intelligence dengan memasukan beberapa parameter yang mempengaruhi konsumsi. Adaptive Neuro Fuzzy Inference System (ANFIS) merupakan suatu sistem yang meng-gabungkan kemampuan jaringan syaraf tiruan dan logika fuzzy. Untuk itu, pada penelitian ini dilakukan prediksi kebutuhan gas bumi menggunakan ANFIS dengan tiga parameter inputan yang dipakai adalah pertumbuhan ekonomi, jumlah penduduk, dan harga gas, sementara output yang dicari adalah kon-sumsi gas bumi. Dari hasil prediksi didapatkan tingkat akurasi 99.203% dan MAPE sebesar 1.2855 %. Sehingga dapat disimpulkan bahwa ANFIS dapat digunakan sebagai metode proyeksi kebutuhan konsumsi gas bumi Indonesia.

The oil production process is the process of extracting oil from the reservoir using the wells that have been made. In the production process there are three stages, namely primary recovery, secondary recovery and tertiary recovery. At the primary recovery stage there are two methods, namely production using natural reservoir energy (natural flow) and production using artificial lift methods (artificial lift). There are two basic principles of artificial lift, namely gas lift and pumps. The principle of the gas lift is to inject gas into the bottom of the well thereby reducing the density and pressure gradient of the reservoir fluid so that the fluid flows more easily. While the principle of the pump is to provide additional energy (head) to lift the fluid. The type of pump that is often used for shallow wells is Sucker Rod Pump. The performance of the sucker rod pump is influenced by the characteristics of the well and reservoir such as pressure, well productivity, physical properties of the fluid, as well as the depth of the well and the dimensions of the sucker rod pump. In this study, the factors studied were the physical properties of the fluid, namely the API of the fluid with variations of API 15o and API 45o, as well as the pump volumetric efficiency (Ev) of 90% and 70%. From the analysis carried out, the results obtained a). For API 15° and Ev 90% fluids: 759 stb/day and 39 hp prime mover power; and for API 15° and Ev 70%: 591 stb/day and prime mover power of 32.2 hp. b). For API 45° and Ev 90% fluids: 783 stb/day and prime mover power of 34.3 hp; and for API 45° and Ev 70%: 609 stb/day and prime mover power of 28.6 hp.

Energy needs in the future will continue to grow along with the growth of the population. Renewable and non-renewable energy sources continue to develop with various innovations. However, energy consumption from non-renewable energy such as coal, oil, and natural gas still dominates. Therefore, one of the potential non-renewable energy sources that can be optimized at present is unconventional oil and gas reserves. Unconventional oil and gas are oil and gas that comes from sourcerock, low permeability reservoirs, such as shale oil, shale gas, tight sand gas, coal bed methane, and methane-hydrate. To produce oil and gas from the tight sand gas reservoir, the hydraulic fracture method is a commonly used method. A hydraulic fracture is a well stimulation technique in which rock is fractured by a pressurized liquid. The process involves the high-pressure injection of fracking fluid into the wellbore to create crack in the deep rock formation through which natural gas, petroleum and brine will flow more freely. When the hydraulic pressure is removed from the well, small grains of hydraulic fracturing proppants hold the fracture open. Well log data such as gamma ray log, SP log, density log, resistivity log and so on will be processed and produce shale volume, porosity, permeability, and water saturation. Procced data from well log will be validated by core data. These data will be input into a reservoir model. A hydraulic fracture design will be made in the reservoir model with a certain length, width, and permeability using the uniform conductivity rectangular fracture method. The simulation will continue by using different length fracture design so that the optimum fracture length value is obtained. Keywords: Hydraulic Fracture, Reservoir Modelling, Reservoir Simulation

Geothermal energy is a renewable alternative energy source. One of the analyses used to determine the characteristics of a geothermal field is water geochemical analysis. The target of this research is the Blawan-Ijen geothermal prospect area, Bondowoso. The geochemical analysis was carried out using AAS, Spectrophotometer and acid-base titration. This survey shows the characteristics of the geothermal system and geothermal fluid in the Blawan area, Ijen. From the chemical analysis of hot water, we found that the types of geothermal water fluids in the Blawan Ijen area vary. In samples BL1, BL2 and BL5 included in the type of Sulphate Water with the dominant elemental Sulphate (SO4) content is also known as Sulfuric Acid Water (Acid-Sulphate Water). Then for the BL4 sample included in the type of chloride water. This type of water is a type of geothermal fluid found in most areas with high-temperature systems. Areas with large-scale hot springs flowing with high Cl concentrations originate from deep reservoirs and indicate permeable zones in those areas. However, this area may not be located above the main upflow zone. There are several other possibilities, such as topographic influences, which can significantly impact hydrological control. The presence of chlorine gas can also identify high zones' permeable areas (e.g., faults, breccia eruptions or conduit). In contrast, BL3 samples are included in the Bicarbonate Water-type. The element HCO3 (bicarbonate) is the most dominant element (main anion) and contains CO2 gas from the chemical analysis results. HCO3 water is generally formed in marginal and near-surface areas in systems dominated by volcanic rocks, where CO2 gas and condensed water vapour into groundwater. The vapour condensation can either heat the groundwater or be heated by steam (steam heated) to form an HCO3 solution