The whole premise of THE MATRIX is flawed. The machines are using humans as a power source - WHAT? Yes, humans, and all animals, radiate heat, but they never radiate more energy than they consume. Any physicist will tell you that it will take more energy to produce food and transport it to the humans than will ever be gotten from the humans. The humans are an energy sink. It doesn't matter how high-tech the machines supposedly are. You can't overcome the laws of thermodynamics.