Here's another surprise from my experience in a Formula E car: the electric racers don't charge using power from the grid. Juice is supplied by a generator, but it's not running gas or diesel or some kind of synthesized alien blood. It's using a pollution-free, non-toxic glycerine. I drank some and wasn't bent over a toilet afterwards. UPDATE.
If there's one over-arching complaint from opponents of electric cars, it's where the power comes from. Depending on the country and the market, electricity generation could be as clean as solar or as dirty as coal. Formula E wanted to squash that issue right out of the gate.
The series partnered with Aquafuel Research, which has a deal with one of the world's largest biofuel suppliers, Greenergy. For every nine gallons of biodiesel Greenergy produces, there's one gallon of crude glycerine as a byproduct. Normally it's used for everything from lubrication to cosmetics, but as biodiesel production ramped up, the supply of glycerine outstripped demand.
Aquafuel saw an opportunity to use the stuff as a fuel thanks to its energy density, high oxygen content, and ability to burn cleaner than standard diesel, with low NOx emissions, a 90-percent decrease in particulates, and no smoke.
For the race, Formula E uses a single diesel generator – yes, one – a lightly-modified Cummins KTA50 to charge all 40 racers from flat to full in around 50 minutes. The cars are hooked up 20 at a time, with 42 kW of energy provided to each car for a total of 840 kW – enough to power a couple thousand homes. [UPDATE: Several eagle-eyed commenters point out that the generator in the picture above isn't large enough to be the Cummins mentioned in the article. This generator was at Homestead during my time driving one of the Formula E cars, so it's not the same one used during the actual race.]
In addition to burning cleaner, the glycerine lubricates better than diesel thanks to its lack of soot and particulates, which boosts the generator's efficiency. It's also water-soluble and odorless.
As for how it tastes: it's sweet and syrupy, like corn syrup or something approximately cough meds, but without the alcohol flavor. I wouldn't want to take more than a shot of the stuff, but the fact I wasn't confined to the trackside toilets afterwards was proof enough for me.