Animal Energy
For thousands of years the world ran not on oil but on muscles. Mostly they were not our own.
Before steam, diesel and electricity came, there was an energy source that ploughed, pulled, carried and milled: the animal. Horses, oxen, donkeys, mules, as well as camels and water buffalo were for thousands of years the strongest engines available to humankind. Whoever understands their role sees how young our world of machines really is and how much it builds on a hidden prehistory.
The living engine
A person can sustain only about 100 watts of muscle power. A working horse manages a multiple of that: roughly five to seven times as much, over a working day. An ox pulls more slowly, but incredibly steadily and stubbornly straight ahead, ideal for the heavy plough. That was exactly the point: a farmer alone could hardly break up a stony field, but with a team of oxen he accomplished in one day what would otherwise have taken him a week.
This power was so formative that we still carry it in our language today. When a car has 120 "hp," we mean horsepower. James Watt, the inventor of the practical steam engine, deliberately chose the horse as a measure because every buyer immediately understood how many animals his machine replaced.1 The engine was measured against the animal, not the other way round.
What an animal really produces, and what it costs
Animals look like "free" energy, but that is deceptive. An ox or horse must be fed, every day, even when it is not working. It needs pasture or oats, that is, land that then does not serve human nutrition. Historians estimate that in the age of horse-based farming a considerable part of the arable land went solely to feeding the draft animals. Added to that are water, stable, care, illness and rest periods.
An animal, after all, is not a tool you can put in the corner but a living being with its own needs. That made animal energy at once valuable and expensive. Whoever owned draft animals owned power: he could cultivate more land, transport more, trade more. Whoever had none remained dependent on their own hands. Energy was always unequally distributed, long before there were electricity bills.
Transport, trade and war
Without animals there would have been neither long-distance trade nor great empires. The caravans that carried silk and spices across continents ran on camels. Post, troops and goods rolled on horse-drawn wagons. Even the world wars of the 20th century devoured millions of horses that pulled guns and supplies where trucks failed in the mud.
It is easy to forget how deeply this animal power shaped our cities. A good hundred years ago, big cities were practically suffocating in horse manure, an environmental problem that hardly anyone knows today. The car was regarded back then, of all things, as the clean solution. A sobering thought: almost every new energy technology promises to fix the problems of the old one, and in doing so creates new ones that only become visible later.
Why this still matters today
The look at animal energy is more than nostalgia. It makes three things visible that are important for critical thinking about energy.
First: power was never free. Even the seemingly natural energy of the animal cost feed, land and care. Whoever today speaks of "free" sun or wind should ask just as closely about the hidden costs.
Second: energy is power. Whoever had draft animals at their disposal could achieve more than others. The same pattern repeats itself with every form of energy to this day, only that now it is about oil fields, grids and power plants.
Third: progress always has two sides. The machine freed countless animals and people from brutal drudgery, a genuine gain in dignity. At the same time it made us dependent on fuels whose consequences we are still paying off today.
In many parts of the world, by the way, animals still pull the plough and carry the loads, not out of romanticism but because diesel is expensive and electricity unreliable. Animal energy is thus by no means a thing of the past. It reminds us that the comfortable world of engines is a young, dearly bought exception and not a self-evident normal state.