We always talk about the power of the human brain but now researchers are considering ways to use what powers the brain to power chips that may be implanted in the future to restore some brain functions. That is using glucose for generating electrical power. This is what our (and all life) cells are doing. At the cell level the glucose (sugar) is user to create ATP (Adenosine triphosphate), the power molecule for the cell.
Scientists at the MIT have created a fuel cell that can make use of the glucose present in the CSF (CerebroSpinal Fluid) to create a few hundreds microwatt of power. The fuel cell strips electrons out of the glucose molecule using a platinum electrode. The idea is to use this fuel cell to power brain implants, something that is becoming possible thanks to the decrease in power consumption of electronic circuits.
The glucose contained in the CSF is not used by the brain so the device will not “starve” it; another plus is that the CSF does not contain cells (basically) hence it does not react to foreign bodies.