First few paragraphs quoted below, but worth reading the whole report. Very interesting, good find @Parax
"British-based company Aquafuel, a specialist in renewable power innovation, is to supply the new FIA Formula E Championship with one of its highly-advanced glycerine (glycerol) generators, to be used to charge all 40 Spark-Renault SRT_01E cars at all race events.
Working with the UK’s leading fuel company Greenergy, Aquafuel has developed ground-breaking new technology for the combustion of glycerine in standard diesel generators. Located in the paddock, these generators will be used at all ePrix with the sole purpose of ensuring the Formula E cars are charged quickly, safely, fairly and without producing CO2 emissions.
Using a single generator, all 40 cars can be charged from flat to full in 50 minutes and with automated precise power controls, can be relied upon to ensure no car is given additional power."