Of course, your calculations of energy consumption are for a normal human. The gastrointestinal system not only produces energy, but consumes it as well. For a photosynthetic human, a smaller gastrointestinal system could result in less power consumption. Likewise, transporting energy could become more efficient, in that it could be less centralized; tasks such as hair growth could use the energy from the surrounding photosynthetic skin, rather than the food energy (of course, the actual material must be pulled from the food).
That said, I know zilch about biology, as I'm sure my post made evident.
Slashdot Mirror
Of course, your calculations of energy consumption are for a normal human. The gastrointestinal system not only produces energy, but consumes it as well. For a photosynthetic human, a smaller gastrointestinal system could result in less power consumption. Likewise, transporting energy could become more efficient, in that it could be less centralized; tasks such as hair growth could use the energy from the surrounding photosynthetic skin, rather than the food energy (of course, the actual material must be pulled from the food). That said, I know zilch about biology, as I'm sure my post made evident.