Pompa hydram telah banyak diaplikasikan terutama di daerah pedesaan atau perbukitan dimana ketersediaan suplai energy listrik menjadi kendala. Pompa hydram adalah pompa mekanis yang memanfaatkan peningkatan tekanan (water hammer) yang terjadi akibat mekanisme penutupan katup limbah secara tiba-tiba. Untuk itu pada badan pompa hydram dipasang tabung udara untuk mengurangi denyutan aliran air hasil pemompaan. Dalam kurun waktu tertentu operasi pompa hydram, jumlah udara yang ada dalam tabung udara akan terus berkurang. Untuk menggantikan volume udara dalam tabung udara tersebut maka pompa hydram dilengkapi dengan katup penghirup udara (snifter-valve). Namun dalam implementasinya, katup ini hanya berupa lubang berdiameter 1 ÷ 2 mm pada jarak sekitar 2 cm di bawah katup tekan pada badan pompa hydram. Namun sampai saat ini belum ada acuan diameter lubang snifter-valve tersebut. Oleh sebab itu, pada penelitian ini diinvestigasi besarnya peningkatan tekanan yang terjadi dalam tabung udara pompa hydram. Pada penelitian ini pompa hydram dilengkapi dengan katup hirup dengan variasi diameter lubangnya yaitu 0,5, 1,0, 1,5, 2,0 dan 2,5 mm. Hasil penelitian menunjukkan bahwa pada model pompa hydram dengan pipa penggerak berdiameter 1¼ inchi yang diuji, peningkatan tekanan yang terjadi dalam tabung udara berkisar antara 0,4 sampai dengan 0,5 bar. Snifter-valve dengan lubang berdiameter 1,5 mm menghasilkan peningkatan tekanan water hammer tertinggi dalam tabung udara sehingga memberikan kerja tertinggi yang terjadi dalam pompa hydram. Hydraulic ram pumps have been implemented and installed mainly in hilly or remote area where they are facing public electrical supply problem. Hydraulic ram pumps are mechanical pumps that utilize the increased water hammer due to the sudden shutdown mechanism of the waste valve. Therefore, the hydraulic ram pump is equipped with air vessel to reduce the pulsation of the pumping water flow. Within a certain period of hydraulic ram pump operation, the amount of air present in the air vessel will continue to decrease. In order to replace the air volume in the air vessel, the hydraulic ram pump is equipped with a snifter-valve. However, in its implementation, this valve is only a hole with a diameter of 1 ÷ 2 mm at a distance of about 2 cm below the delivery valve on the body of the hydraulic ram pump. However, there has not been any reference for determining the diameter of the snifter-valve hole yet. Therefore, in this study, works carried out for investigating the magnitude of the increased pressure that occurs in the air vessel of hydram pump. In this study, a hydraulic ram pump equipped with a snifter-valve with various orifice diameters of 0.5, 1.0, 1.5, 2.0 and 2.5 mm. The results show that for the hydraulic ram pump model with 1¼ inch diameter of the drive pipe that tested, the incrising pressure in the air vessel is about 0.4 up to 0.5 bar. The snifter-valve with 1.5 mm orifice diameter generates the highest incrising pressure of water hammer pressure in the air vessel, therefore, it gives the maximum work in the hydraulic ram pump.

The power system must be able to server the load in a sustainable manner with good service quality, such as constant voltage and frequency, quickly stabilized when load changes occur. The control generator automatically changes the frequency to the highest value when the system changes every time. This is called AGC. To keep the frequency in a stable state required frequency control system. Currently developing a lot of control system with fuzzy logic method. The simulation is performed using 5 membership functions and gives a loading of 0.1 pu, using MATLAB-Simulink software. From the analysis result, the comparison of output of frequency response in overshoot condition with conventional method yielded , settling time of 20.5 second. While the fuzzy logic controller method produces frequency response output in the overshoot state that is , settling time is 12 seconds. Whit the fuzzy logic controller method produces better performance and faster than conventional methods.

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Bali memiliki banyak sumber energi aliran air  sungai atau saluran irigasi yang mempunyai debit aliran relatif kecil pada head yang rendah, dengan demikian Hydropower dapat memberikan solusi praktis terhadap masalah konservasi energi dan masalah lingkungan. Pada penelitian ini didesain model kincir sudu melengkung ke belakang (back curve vanes) skala laboratorium, mengikuti kaidah-kaidah desain turbin air, dengan metode satu busur lingkaran, sehingga pengusaha bengkel nanti dapat membuat sudu kincir air dari potongan pipa besi. Data-data yang  diamati adalah : kapasitas aliran (Qa), head  (Ha), putaran kincir (n),  pada setiap variasi beban, sudut  aliran air masuk sudu,  dan sudut kelengkungan sudu dengan demikian menjadi jelas karakteristik dari kincir air. Empat sudu yang diuji memiliki sudut kelengkungan sudu (?) yang berbeda yaitu 10o, 20o, 30o dan 40o, sudut air masuk (?1) yaitu 2/5 ?, 3/5 ?, 4/5 ? dan 5/5 ?. Hasil penelitian menunjukkan bahwa unjuk kerja sudu lengkung ke belakang dengan besarnya sudut aliran air masuk sudu (?1) yang sesuai/sama dengan sudut kelengkungan sudu (?) akan menghasilkan unjuk kerja yang paling baik. Empat sudu yang diuji pada konstan dan variasi kapasitas maka   sudut kelengkungan sudu (?) = 20o menunjukkan hasil terbaik. Semakin kecil sudut kelengkungan sudu maka unjuk kerja akan semakin baik dalam batas toleransi atas meningkatnya kerugian gesekan/hidrolis dari fluida kerja yang terjadi. Bali has many sources of river water streams or irrigation channels that have relatively small flow discharge at low head, thus Hydropower can provide practical solutions to energy conservation and environmental issues. In this research, the model is designed for the back curve vanes of laboratory scale, following the rules of water turbine design, with the method of one circular arc, so that the workshop entrepreneur can make the waterwheel from the iron pipe binder. The observed data are: flow capacity (Qa), head (Ha), rotation (n), at each load variation, angle of the water entering the blade, and the angle of the blade curvature thus becomes clear the characteristic of the waterwheel. Four tested blades have different angle of curvature (?) that is 10o, 20o, 30o and 40o, the inlet angle (?1) is 2/5 ?, 3/5 ?, 4/5 ? and 5/5 ?. The results showed that the performance of the back end curve with the angle of the water flow in the blade corresponding to the angle of curvature of the blade (?) will produce the best performance. Four blades tested at constant and capacity variation then angle curvature angle (?) = 20o shows best result. The smaller the angle of the blade curvature, the better the performance within the tolerance limit of the increased friction / hydraulic losses of the working fluid that occurs.

A good electrical power system is a system that can serve the load in a sustainable and stable voltage and frequency. Changes in frequency occur due to the demand of loads that change from time to time. The frequency setting of the PLTG power system depends on the active power charge in the system. This active power setting is done by adjusting the magnitude of the generator drive coupling. The frequency setting is done by increasing and decreasing the amount of primary energy (fuel) and carried on the governor. Simulation in governor analysis study as load frequency control at PLTG using fuzzy logic controller is done by giving four types of cultivation that is 0,1 pu, 0,2pu, 0,3 pu and 0,4 pu. The simulation is done to compare the dynamic frequency response output and the resulting stability time using fuzzy logic controller with PI controller. Based on the results of comparative analysis conducted to prove that governor as load frequency control using fuzzy logic control is better than using PI controller. This can be seen from the output response frequency and time stability.