We also use 100 million barrels of oil every day. Each barrel carries equivalent energy to ten years of human labour. Let's forget for a moment about other ene

We also use 100 million barrels of oil every day. Each barrel carries equivalent energy to ten years of human labour. Let's forget for a moment about other energy sources, and also pretend we use all that oil just for energy. That would mean that every day, the 8 billion humans on Earth are using the same energy that it would take 365 billion humans to provide by hand.