The research analyzes benefit cost and break even point including sensitivity of making biodiesel production factory from palm fatty acid. Biodiesel production system of Thailand Institute of Scientific and Technological Research (TISTR) is used for this study. It is found the present net value has been a deficit of 27024966 baht. The sensitivity of the project has been analyzed by increasing selling price of biodiesel of 5% and 7.5% but reducing material price of 10% and 20%. It is found the present net value still has been deficient. The project will payback at 5th 8th and 10th year be with selling price of biodiesel. is about 31.71 baht per litre. Therefore the cost of palm fatty acid should lower than 2.89 3.05 and 3.82 baht per kilogram. If selling price of biodiesel about 33.30 baht per litre the cost of palm fatty acid should be lower than 4.65 4.82 and 5.58 baht per kilogram. respectively.

This thesis proposes technical performance evaluation and economic decence for the combination of harmonic correction devices in Industry. Currently an electronic device is popularly applied in power network. Although it is a higher performance device than the existing device it still causes the power quality issues and then network failure. Especially harmonic disturbance in the network it is a harmonic source that generates harmonic current into the network. Many types and solutions are available in the present time therefore the suitable and optimal financial solution must be considered. A network model for the analysis of harmonic correction devices suitable solutions and optimal financial has been established in the simulation software that bases on the power and Break Even Point (BEP) equations. The results of analysis shown that the performance of harmonic correction devices suitable solution and BEP of investment in match to the using of a detuned filter bank and an active harmonic filter (case 8) thus these information will be valued for the end-user.