Speaker 1: Stuff happens, just don't let it happen to your photos, music,
Speaker 1: and documents. Protect your important files with Mosey by e
Speaker 1: m C, the most trusted name and cloud backup. Save
Speaker 1: ten percent today with promo code brain Stuff at mosey
Speaker 1: dot com. That's m o z Y dot com. Welcome
Speaker 1: to brain Stuff from how Stuff works dot com where
Speaker 1: smart happens. I am Marshall Brain with today's question, what
Speaker 1: are all the different ways to store energy? Besides using
Speaker 1: rechargeable batteries. Human beings have been looking for a good
Speaker 1: way to store energy for a long time. One of
Speaker 1: the big things that's been holding up electric cars is
Speaker 1: battery technology. When you compare batteries to gasoline, the differences
Speaker 1: are huge. For example, a typical electric car might carry
Speaker 1: a thousand pounds of lead acid batteries. Those batteries take
Speaker 1: several hours to recharge, and they might give the car
Speaker 1: a hundred mile range. Two or three gallons of gasoline
Speaker 1: give the same range. Weigh less than thirty pounds, and
Speaker 1: you can pump that much gasoline in about a minute.
Speaker 1: There's really no comparison between gasoline and batteries. Here's a
Speaker 1: list of some of the other technologies that people commonly
Speaker 1: use to store energy. Some of these working electric car
Speaker 1: while others are better off for stationary applications. One of
Speaker 1: the oldest techniques people have used is the falling weight.
Speaker 1: You lift the weight to store the energy in it,
Speaker 1: and then you let the weight fall to extract the energy.
Speaker 1: Many grandfather clocks and cuckoo clocks use this technique. By
Speaker 1: running the string attached to the weights through a gear train,
Speaker 1: you can use a heavy weight and let it fall
Speaker 1: over a long period of time. This approach doesn't work
Speaker 1: very well in an electric car, but it's worked well
Speaker 1: in clocks for hundreds of years. Many power plants use
Speaker 1: the falling weight approach in the form of water. The
Speaker 1: water is pumped uphill to a lake at night when
Speaker 1: the power plant has excess capacity, and then during high
Speaker 1: demand daytime periods, the water runs through a termite on
Speaker 1: its way downhill to a lower lake. Another way to
Speaker 1: store energy is in some form of repeatable mechanical deformation.
Speaker 1: This is the idea behind a spring used in a
Speaker 1: wind up clock or a rubber band used in a
Speaker 1: wind up airplane. You store the energy by deforming the
Speaker 1: material in the spring and the material releases that energy
Speaker 1: as it returns to its original shape. At the scale
Speaker 1: of a car, this technology has problems because of the
Speaker 1: weight of the spring, but it's smaller scales like a
Speaker 1: wrist watch, it works great. Nature has been storing energy
Speaker 1: for a long time, and if you want to think
Speaker 1: about it this way, gasoline is really a form of
Speaker 1: stored natural energy. Plants absorbed sunlight and turn it into
Speaker 1: carbohydrates over millions of years, those carbohydrates can turn into
Speaker 1: oil or coal, and that's a form of stored energy.
Speaker 1: On a more human time scale, we burn wood to
Speaker 1: release stored energy stored in the plant, or we turn
Speaker 1: corn into alcohol and burn the alcohol. Another technique that
Speaker 1: nature uses the store energy is fat, which many of
Speaker 1: us are familiar with in a personal way. It's interesting
Speaker 1: to think about a car that somehow eats grass or
Speaker 1: some other form of carbohydrate and stores it is fat.
Speaker 1: You can take energy and split water into its hydrogen
Speaker 1: and oxygen atoms using electrolysis. By storing the hydrogen, you
Speaker 1: can later create energy by burning it or by running
Speaker 1: it through a fuel cell. You can use energy to
Speaker 1: spin up a flywheel and then later extract the energy
Speaker 1: by using the flywheel to run a generator, or you
Speaker 1: can store heat directly and later convert the heat to
Speaker 1: another form of energy like electricity. Molten salt is one
Speaker 1: way to do this. You can use compressed air to
Speaker 1: store energy, or you can compress air a lot and
Speaker 1: get something like liquid nitrogen and use the liquid nitrogen
Speaker 1: to power a car. One of the new technologies that
Speaker 1: may become available in the future involves antimatter. When you
Speaker 1: combine matter with antimatter, you get energy. You can store
Speaker 1: energy by creating anti matter. Right now, none of these
Speaker 1: techniques can hold a candle, which is really another form
Speaker 1: of stored energy, to gasoline in the convenience sense. Fuel
Speaker 1: cells look to be the closest competitor right now, and
Speaker 1: they'll probably become available to the general public over the
Speaker 1: next few years. For more on this and thousands of
Speaker 1: other topics, is it how stuff works dot Com. Your photos,
Speaker 1: music and documents are irreplaceable. Protect them with Mosey by
Speaker 1: e m C, the most trusted name and cloud back up.
Speaker 1: Back up your files today and save ten percent with
Speaker 1: promo code. Brain Stuff at Mosey dot com, m o
Speaker 1: z y dot com