Bio-electricity

[Taem]

So I was thinking about our marvelous bodies the other day, and came to realize that for a very small amount of food (half a fist), our bodies are capable of converting the nutrients from that into hours and hours of physical labor through muscle contortions. Furthermore, those nutrients allow the body to heat itself, and run a mild electrical current to keep the pistons firing. Additionally, our waste can be used as fertilizer and methane gas. If someone were to find a way to create a non-living bio-engineered "thing" that requires a few drops of water and some sprinkling of fish food and in return outputs "x" amount of hours of physical labor or computing, well I see a real future in that! What is common solar power-to-AC-conversion loss rates? Like 65-70% or more? With bio-electricity, we're talking about a conversion gain, not loss! Think about it, people have put people through terrible tribulations, yet despite meager amount of food and water, human are capable of intense physical labor. Let me put this another way: ex. 1-lb of food = 6-8 hours of physical labor. In this example, the fusion our body does with food outputs incredible energy from such a small amount. I wonder how much energy is the food equal too (sunlight, growth, harvesting). If our example was fed grain or fish food, something that could be grown over time without much oversight, then the cost to produce as opposed to the gain would be out-marginalized by a tremendous amount, meaning very little put in for a huge gain! This could be the holy grail of endless power!