NOVELTY - A system for producing a bio-fuel comprises a reactant containing a bio-substance and an alcohol; a catalyst to be mixed with the reactant; and a radio frequency wave generator for generating a radio frequency wave to be applied to the bio-substance.    USE - For producing a bio-fuel i.e. bio-diesel useful in an engine (claimed).    ADVANTAGE - The method has bio-substance conversion rate of at least 65 (preferably greater than or equal to 90)%. By using radio frequency (RF heating), the method achieves higher production efficiency than microwave heating in bio-diesel production. Compared to microwave heating, the RF heating system are simpler to configure, have higher electricity to electromagnetic power conversion efficiency, and a deeper penetration of RF energy into a wide array of materials. Thus, the RF heating system is more economically feasible than microwave heating, and is more suitable to be applied in large commercial scale reactors.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) method (m1) of generating a bio-fuel involving either: mixing a bio-substance with an alcohol and an ion source, and applying a radio frequency wave to the bio-substance; or reacting a bio-substance with an alcohol through a transesterification reaction, and assisting the transesterification reaction by applying a heating method, where the heating method is performed by changing a phase of an electromagnetic field, and the electromagnetic field further includes a wave with a wavelength longer than a microwave frequency wave; or performing catalytic transesterification of a bio-molecule with the assistance of a polarized force having a frequency lower than the frequency of a microwave; and    (2) method of providing a bio-fuel to an engine involving providing bio-substance, catalyst and alcohol to a bio-fuel reactor; exposing the bio-substance to a radio frequency wave for a predetermined amount of time to generate the bio-fuel; and providing the bio-fuel to the engine.