Probably did this the same way the old fill your gas tank with water and drop in this special pill scam worked. Secret gas tank hidden someplace in the car
Well, Duh!!
For all I know, he could have had lemmings running on a wheel.
It was a local news story, and they had mechanics check the whole setup before/after the test.
These kinds of reports are like crop circles.
Even if 99.9 percent are outright fraud, all it takes is one to be true.
There is alot of con going on. But that by itself doesn’t make the idea impossible.
This is why I'd like to see this unit run for a month, at a different location, under supervision.
For the case of cars with extraordinary mpg, the test also needs to be to run continuously for a month(using drivers in relays, or on a dynamometer) and see. Hybrid car makers are big culprits in this sort of scam, starting the test with full batteries and not counting their contribution.