Oils from plants and animal fats are hydrolyzed to fatty acids for a Kolbe reaction. The invention relates to a high productivity Kolbe reaction process for electrochemically decarboxylating C4-C28 fatty acids derived from sources selected based on their saturated and unsaturated fatty acid content in order to lower anodic passivation voltage during synthesis of C6-C54 hydrocarbons. The C6-C54 hydrocarbons may undergo olefin metathesis and/or hydroisomerization reaction processes to synthesize heavy fuel oil, diesel fuel, kerosene fuel, lubricant base oil, and linear alpha olefin products useful as precursors for polymers, detergents, and other fine chemicals.