Increased energy consumption in Indonesia encourages energy conservation in the field of renewable energy. One form of energy that has been increasingly developed is the use of biodiesel as vehicle fuel. The process of biodiesel production can be done by various methods, such as the use of induction technology as a heat supply media in the transesterification reaction. This induction technology uses a non-contact process that utilizes magnetic field radiation in the metal so that it will generate heat from inside the metal material. The raw material used in this research is waste cooking oil by varying the reaction temperature used. Based on research that has been done, obtained high yield results at the use of a temperature of 60 degree C for the use of used cooking oil is 86.95 percent and the biodiesel products obtained are by the applicable quality standards in Indonesia.

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The performance of electro coagulation system with aluminum and iron electrodes to remove heavy metals from actual wastewater of coal's stockpile which has studied. The effects of process variables such as electrode material, current density and operation time for electro coagulation process are investigated on ferrous and manganese removal efficiencies. Preliminary results show that the electro coagulation process is able to enhance the removal of heavy metal contents. The batch experiment results showed that the high heavy metals which is contained wastewater coal's stockpile can be effectively treated by electro coagulation system using aluminum electrodes. The overall removal efficiencies of heavy metals have been obtained at 89.7% for ferrous and 94.6% for manganese, respectively. The removal rates of those elements were increase with operation time. Therefore, electro coagulation technique to remove high content of heavy metal and TSS from wastewater of coal's stockpile is found effective and friendly with the environment.

The target of increasing the use of renewable fuels is directly proportional to the increasing demand for biodiesel. High demand for biodiesel must be balanced with sufficient availability from producers. One of the factors that influence biodiesel conversion rate is the use of catalysts. The use of sodium teoxide (CH3ONa) catalyst in the manufacture of biodiesel can be applied in the process of biodiesel production using induction heating technology. This technology will accelerate the heating process needed in the transesterification reaction. Based on research that has been done, the use of a catalyst concentration of 1% will produce a yield of 86.95% with product quality in accordance with SNI such as density 0.858 gr/cm3, viscosity 5.727 cSt, flash point 190°C, and acid number 0.439 mg-KOH/gr.

Plastic is overused in every life application resulting in the accumulation of plastic waste that takes a long time to decompose. An alternative way of handling plastic waste today is to convert plastic waste into fuel oil or called plastic pyrolysis process. Pyrolysis is a chemical decomposition of organic matter through a process of heating without or little oxygen in which the raw material will break the chemical structure into a gas phase. One of the factors affecting the pyrolysis process is the heating temperature in the reactor. In this research, the design of the plastic waste pyrolysis tool using the thermal cracking method with a capacity of 500 grams using infrared heating element. The raw materials used are Polypropylene type plastic. The independent variables are temperature variations in the reactor, i.e., 250°C, 300°C, and 350°C. The dependent variable is the mass of plastic waste, operating time, and operating pressure. From the research results, the higher the heating temperature in the reactor, the higher the % yield, density, specific gravity, and volume of liquid product produced. Conversely, the higher the temperature, the lower API Gravity, Heating Value, and Flash Point are.