- Albert Bartlett
We know that energy is used during food production, but if only someone would run the calculations to see how much. Well, this guy (David JC MacKay) has. And he’s run the numbers on solar, wind, flying, cars and every other energy-generating and energy sucking activity out there.
Food is perhaps my personal favorite. While I’m sure I can give up flying, I’m not so sure I can give up eating.
According to some estimates, it takes 10 calories of energy to produce 1 calorie of food energy. We can sustain this imbalance as long as we have the cheap fossil fuel subsidy, but it won’t last forever. When the shit hits the fan, will owning a chicken provide a net positive caloric energy return on investment? Here’s what MacKay says:
A “layer” (a chicken that lays eggs) eats about 110 g of chicken feed per day. Assuming that chicken feed has a metabolizable energy content of 3.3 kWh per kg, that’s a power consumption of 0.4 kWh per day per chicken. Layers
yield on average 290 eggs per year. So eating two eggs a day requires a power of 1 kWh per day. Each egg itself contains 80 kcal, which is about 0.1 kWh. So from an energy point of view, egg production is 20% efficient.
