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We're consuming one thousand liters of gasoil every 11 nautical miles, that is more or less one thousand times more expensive than the most economic Japanese car.
This guy however, is following us for the last four hundred nautical miles, turning circles around us constantly, and he is doing all this only on a couple of fresh fish a day.
As human, we have a long way to go if we are talking about economic energy use. But look at his aerodynamics, it is perfect.