NOVELTY - Making biodiesel fuel (A) and fuel additive products (A1) comprises improvements of directing radio frequency microwave energy into: a first mixture (II) prior to the first separation for reducing the amount of unreacted alcohol and glycerin retained in a biodiesel product (III); or a second mixture (V) prior to the second separation for reducing a washing agent (IV) retained in (III).    USE - The invention relates to the production of biodiesel (claimed).    ADVANTAGE - The process is improved and involves directing radio frequency microwave energy (claimed). The process is cost effective and efficient.    DETAILED DESCRIPTION - Making biodiesel fuel (A) and fuel additive products (A1) comprising reaction of a triglyceride-containing feed stock (I) with an alcohol in the presence of a transesterification catalyst to form a first mixture (II) of biodiesel product, alcohol and glycerin, subsequently separation of (II) in a first separation for separating the biodiesel product (III) from unreacted alcohol and glycerin, subsequently washing of (III) with a washing agent (IV) to produce a second mixture (V) of (III) and (IV) and subsequently subjecting (V) to a second separation for separating (III) from (IV), where the process comprises improvements of directing radio frequency microwave energy into: (II), prior to the first separation for a time sufficient to reduce an amount of unreacted alcohol and glycerin retained in (III) and to reduce a time required for separating (III) from the unreacted alcohol and glycerin; or (V) prior to the second separation for a time sufficient to reduce an amount of (IV) retained in (III) and to reduce a time required for separating (III) from (IV). INDEPENDENT CLAIMS are included for:    (1) a method of enhancing a transesterification reaction rate and biodiesel product yield for production of (A) and (A1), comprises applying radio frequency microwave energy prior to the separation of (III) to increase the transesterification reaction rate and to drive the reaction equilibrium towards biodiesel production to increase the yield of (III) available for the recovery from the unreacted alcohol and glycerin;    (2) a method of reducing the free fatty acid content of (I) used for the production of (A) and (A1) comprising reaction of (I) having a first free fatty acid content (VI) with a reactant to produce a treated mixture (VII), application of radio frequency microwave energy to (VII) to produce (I) having a second free fatty acid content (VIII) (which is less than (VI)), and separation of (I) having (VIII) from a byproduct waste emulsion, where the radio frequency microwave energy is applied prior to the separation of (I) to reduce an amount of free fatty acid retained in (I) and to increase (I) having (VIII) recovered from the byproduct waste emulsion; and    (3) a system for preparing (A) and (A1).