More recently, hybrid car-makers have had programs to take back and safely dispose of used or damaged high-voltage battery packs for 15 years. Those nickel-metal-hydride cells contain precious metals with a known recycling value.
The term secular stagnation was originally coined by Alvin Hansen in 1938 to describe what he feared was the fate of the American economy following the Great Depression of the early 1930s: a check to economic progress as investment opportunities were stunted by the closing of the frontier and the collapse of immigration.
For the purposes of this article, we'll use the term hibernation to describe any long-term reduction in body temperature (hypothermia) and metabolism during winter months. When an animal enters a hibernationlike state during the summer, it's known as estivation. It's much less common than hibernation. Hibernation in reptiles is sometimes called brumation. It differs from mammalian hibernation because reptiles are cold-blooded -- they can't control their own body temperature, so they need to spend the winter in a place that will stay warm enough.