There is an increasing demand for alternative fuels that are environmentally friendly, especially because of the fact that crude petroleum reserves are dwindling. Also, research on alternative fuels is essential for increased energy security. Biodiesel is a renewable, biodegradable, and nontoxic fuel. At present, biodiesel is primarily produced in batch reactors in which the required energy is provided by heating accompanied by mechanical mixing. Alternatively, ultrasonic processing is an effective way to attain required mixing while providing the necessary activation energy. We found that, using ultrasonication, a biodiesel yield in excess of 99% can be achieved in a remarkably short time duration of 5 min or less in comparison to 1 h or more using conventional batch reactor systems.