CoachAn energy store is anything holding energy ready for use. The great everyday stores: food (your body’s fuel), fuels like wood and petrol, charged batteries, a wound-up spring, water held high behind a dam — and the hot Sun, pouring energy down on everything, all day, for free.
Examples
Example 29.3 (Spot the store)
Every going thing has a store behind it. The scurrying toy: its wound spring. The flashlight: its batteries. The car: the fuel in its tank. You: your breakfast. The sailboat: the moving air of the wind. When the store runs empty — spring unwound, batteries flat, tank dry, lunchtime near — the going stops.