In the ongoing saga of Andrea Rossi's energy catalyzer (E-Cat) that promises clean, cheap power for the world, the latest events continue to bring as many questions as answers. Several scientists have performed supposedly independent tests of two E-Cat prototypes under controlled conditions and using high-precision instrumentation. In a paper posted at arXiv.org, the researchers write that, even by the most conservative of measurements, the E-Cat produces excess heat with a resulting energy density that is at least 1 order of magnitude—and possibly several—higher than any other conventional energy source, including gasoline.
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According to the researcher's conservative measurements and calculations, the E-Cat HT and E-Cat HT2 have energy densities of 680,000 Wh/kg and 61,000,000 Wh/kg, respectively. Even with a "blind" evaluation that probably underestimates the energy production significantly, the researchers still get a value that is an order of magnitude higher than all other conventional energy sources. Considering that gasoline has an energy density of 12,000 Wh/kg, these values are extraordinary and would blow all other energy technologies out of the water.

Here is how Rossi has fooled the bunch of physicist this time:

He has given them the thick insulated cables to measure with a
"clamp ammeters". This type of measurement uses magnetic field created by the current flowing trough a wire. The calculation of the current has an assumption of a single, non-wound and non-shielded wire. However, internal structure of the cables used in this setup were not exposed. It can be seen that they are thick enough to hide things like shielding, winding, or even ferrite rings that could completely distort the magnetic fields and so the validity of the measurement.
It looks like while focusing a lot on temperature measurement, they got fooled by simple electric measurement distortion. Cables are definitely thick enough to deliver
several kW of power while apparent "measured" current would be much less if magnetic field that is being measured is partly shielded. Input power underestimated — "unexplained energy" appears... Rossi did it again!