What are other ways to store energy besides batteries?

a thousand pounds of lead acid batteries. Those batteries take several hours to recharge, and they might give the car a hundred mile range. Two or three gallons of gasoline give the same range way less than thirty pounds, and you can pump that much gasoline in about a minute. There's really no comparison between gasoline and batteries. Here's a list of some of the other technologies that people commonly use to store energy. Some of these working electric car,

while others are better off for stationary applications. One of the oldest techniques people have used is the falling weight. You lift the weight to store the energy in it, and then you let the weight fall to extract the energy. Many grandfather clocks and cuckoo clocks use this technique. By running the string attached to the weights through a gear train, you can use a heavy weight and let it fall

over a long period of time. This approach doesn't work very well in an electric car, but it's worked well in clocks for hundreds of years. Many power plants use the falling waight approach in the form of water. The water is pumped uphill to a lake at night when the power plant has excess capacity, and then during high demand daytime periods, the water runs through a termit on its way downhill to a lower lake. Another way to store energy is in some form of repeatable mechanical deformation.

This is the idea behind a spring used in a wind up clock or a rubber band used in a wind up airplane. You store the energy by deforming the material in the spring, and the material releases that energy as it returns to its original shape. At the scale of a car, this technology has problems because of the weight of the spring, but it's smaller scales like a

wrist watch, it works great. Nature has been storing energy for a long time, and if you want to think about it this way, gasoline is really a form of stored natural energy. Plants absorbed sunlight and turn it into carbohydrates. Over millions of years, those carbohydrates can turn into oil or coal, and that's a form of stored energy. On a more human time scale, we burn wood to release stored energy stored in the plant, or we turn corn

into alcohol and burn the alcohol. Another technique that nature uses the store energy is fat, which many of us are familiar with in a personal way. It's interesting to think about a car that somehow eats grass or some other form of carbohydrate and stores its fat. You can take energy and split water into its hydrogen and oxygen atoms using electrolysis. By storing the hydrogen, you can later create energy by burning it or by running it through

a fuel cell. You can use energy to spin up a flywheel and then later extract the energy by using the flywheel to run a generator. Or you can store heat directly and later convert the heat to another form of energy like electricity. Molten salt is one way to do this. You can use compressed air to store energy, or you can compress air a lot and get something like liquid nitrogen and use the liquid nitrogen to power a car. One of the new technologies that may become

available in the future involves antimatter. When you combine matter with antimatter, you get energy. You can store energy by creating antimatter. Right now, none of these techniques can hold a candle, which is really another form of stored energy, to gasoline in the convenience sense. Fuel cells look to be the closest competitor right now, and they'll probably become a level to the general public over the next few years. Do you have any ideas or suggestions for this podcast?

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