WEBVTT - What are other ways to store energy besides batteries?

0:00:00.560 --> 0:00:03.840
<v Speaker 1>Welcome to brain Stuff from how Stuffworks dot com where

0:00:03.840 --> 0:00:14.880
<v Speaker 1>smart Happens. I am Marshall Brain with today's question, what

0:00:15.000 --> 0:00:18.920
<v Speaker 1>are all the different ways to store energy? Besides using

0:00:18.960 --> 0:00:22.840
<v Speaker 1>rechargeable batteries? Human beings have been looking for a good

0:00:22.840 --> 0:00:25.520
<v Speaker 1>way to store energy for a long time. One of

0:00:25.560 --> 0:00:28.200
<v Speaker 1>the big things that's been holding up electric cars as

0:00:28.280 --> 0:00:32.360
<v Speaker 1>battery technology. When you compare batteries to gasoline, the differences

0:00:32.400 --> 0:00:35.880
<v Speaker 1>are huge. For example, a typical electric car might carry

0:00:35.880 --> 0:00:39.479
<v Speaker 1>a thousand pounds of lead acid batteries. Those batteries take

0:00:39.560 --> 0:00:42.320
<v Speaker 1>several hours to recharge, and they might give the car

0:00:42.400 --> 0:00:45.800
<v Speaker 1>a hundred mile range. Two or three gallons of gasoline

0:00:45.840 --> 0:00:49.120
<v Speaker 1>give the same range way less than thirty pounds, and

0:00:49.159 --> 0:00:51.560
<v Speaker 1>you can pump that much gasoline in about a minute.

0:00:51.800 --> 0:00:56.000
<v Speaker 1>There's really no comparison between gasoline and batteries. Here's a

0:00:56.040 --> 0:00:59.200
<v Speaker 1>list of some of the other technologies that people commonly

0:00:59.320 --> 0:01:02.520
<v Speaker 1>use to store energy. Some of these working electric car,

0:01:02.880 --> 0:01:06.800
<v Speaker 1>while others are better off for stationary applications. One of

0:01:06.800 --> 0:01:10.119
<v Speaker 1>the oldest techniques people have used is the falling weight.

0:01:10.600 --> 0:01:12.640
<v Speaker 1>You lift the weight to store the energy in it,

0:01:12.720 --> 0:01:15.240
<v Speaker 1>and then you let the weight fall to extract the energy.

0:01:15.640 --> 0:01:19.640
<v Speaker 1>Many grandfather clocks and cuckoo clocks use this technique. By

0:01:19.720 --> 0:01:22.559
<v Speaker 1>running the string attached to the weights through a gear train,

0:01:22.720 --> 0:01:25.120
<v Speaker 1>you can use a heavy weight and let it fall

0:01:25.160 --> 0:01:28.280
<v Speaker 1>over a long period of time. This approach doesn't work

0:01:28.360 --> 0:01:31.200
<v Speaker 1>very well in an electric car, but it's worked well

0:01:31.240 --> 0:01:35.080
<v Speaker 1>in clocks for hundreds of years. Many power plants use

0:01:35.160 --> 0:01:38.120
<v Speaker 1>the falling waight approach in the form of water. The

0:01:38.160 --> 0:01:41.240
<v Speaker 1>water is pumped uphill to a lake at night when

0:01:41.280 --> 0:01:44.679
<v Speaker 1>the power plant has excess capacity, and then during high

0:01:44.720 --> 0:01:47.960
<v Speaker 1>demand daytime periods, the water runs through a termit on

0:01:48.000 --> 0:01:51.040
<v Speaker 1>its way downhill to a lower lake. Another way to

0:01:51.080 --> 0:01:55.560
<v Speaker 1>store energy is in some form of repeatable mechanical deformation.

0:01:56.160 --> 0:01:58.520
<v Speaker 1>This is the idea behind a spring used in a

0:01:58.560 --> 0:02:00.800
<v Speaker 1>wind up clock or a rubber band used in a

0:02:00.840 --> 0:02:04.200
<v Speaker 1>wind up airplane. You store the energy by deforming the

0:02:04.240 --> 0:02:08.080
<v Speaker 1>material in the spring, and the material releases that energy

0:02:08.120 --> 0:02:11.320
<v Speaker 1>as it returns to its original shape. At the scale

0:02:11.320 --> 0:02:14.160
<v Speaker 1>of a car, this technology has problems because of the

0:02:14.200 --> 0:02:16.880
<v Speaker 1>weight of the spring, but it's smaller scales like a

0:02:16.919 --> 0:02:20.320
<v Speaker 1>wrist watch, it works great. Nature has been storing energy

0:02:20.400 --> 0:02:22.160
<v Speaker 1>for a long time, and if you want to think

0:02:22.200 --> 0:02:25.240
<v Speaker 1>about it this way, gasoline is really a form of

0:02:25.320 --> 0:02:30.399
<v Speaker 1>stored natural energy. Plants absorbed sunlight and turn it into carbohydrates.

0:02:30.400 --> 0:02:33.800
<v Speaker 1>Over millions of years, those carbohydrates can turn into oil

0:02:33.919 --> 0:02:36.600
<v Speaker 1>or coal, and that's a form of stored energy. On

0:02:36.680 --> 0:02:39.680
<v Speaker 1>a more human time scale, we burn wood to release

0:02:39.760 --> 0:02:43.200
<v Speaker 1>stored energy stored in the plant, or we turn corn

0:02:43.240 --> 0:02:47.080
<v Speaker 1>into alcohol and burn the alcohol. Another technique that nature

0:02:47.200 --> 0:02:49.760
<v Speaker 1>uses the store energy is fat, which many of us

0:02:49.760 --> 0:02:52.840
<v Speaker 1>are familiar with in a personal way. It's interesting to

0:02:52.880 --> 0:02:55.960
<v Speaker 1>think about a car that somehow eats grass or some

0:02:56.040 --> 0:02:59.720
<v Speaker 1>other form of carbohydrate and stores its fat. You can

0:02:59.760 --> 0:03:03.640
<v Speaker 1>take energy and split water into its hydrogen and oxygen

0:03:03.680 --> 0:03:07.720
<v Speaker 1>atoms using electrolysis. By storing the hydrogen, you can later

0:03:07.840 --> 0:03:10.480
<v Speaker 1>create energy by burning it or by running it through

0:03:10.480 --> 0:03:13.400
<v Speaker 1>a fuel cell. You can use energy to spin up

0:03:13.400 --> 0:03:16.480
<v Speaker 1>a flywheel and then later extract the energy by using

0:03:16.480 --> 0:03:19.440
<v Speaker 1>the flywheel to run a generator. Or you can store

0:03:19.480 --> 0:03:22.520
<v Speaker 1>heat directly and later convert the heat to another form

0:03:22.560 --> 0:03:25.760
<v Speaker 1>of energy like electricity. Molten salt is one way to

0:03:25.800 --> 0:03:29.520
<v Speaker 1>do this. You can use compressed air to store energy,

0:03:29.680 --> 0:03:32.200
<v Speaker 1>or you can compress air a lot and get something

0:03:32.280 --> 0:03:35.360
<v Speaker 1>like liquid nitrogen and use the liquid nitrogen to power

0:03:35.360 --> 0:03:38.560
<v Speaker 1>a car. One of the new technologies that may become

0:03:38.560 --> 0:03:42.160
<v Speaker 1>available in the future involves antimatter. When you combine matter

0:03:42.280 --> 0:03:45.760
<v Speaker 1>with antimatter, you get energy. You can store energy by

0:03:45.800 --> 0:03:49.840
<v Speaker 1>creating antimatter. Right now, none of these techniques can hold

0:03:49.840 --> 0:03:52.520
<v Speaker 1>a candle, which is really another form of stored energy,

0:03:52.720 --> 0:03:56.640
<v Speaker 1>to gasoline in the convenience sense. Fuel cells look to

0:03:56.680 --> 0:03:59.720
<v Speaker 1>be the closest competitor right now, and they'll probably become

0:03:59.720 --> 0:04:02.600
<v Speaker 1>a level to the general public over the next few years.

0:04:03.680 --> 0:04:06.559
<v Speaker 1>Do you have any ideas or suggestions for this podcast?

0:04:06.960 --> 0:04:09.640
<v Speaker 1>If so, please send me an email at podcast at

0:04:09.640 --> 0:04:12.360
<v Speaker 1>how stuff works dot com. For more on this and

0:04:12.400 --> 0:04:14.760
<v Speaker 1>thousands of other topics, go to how stuff works dot

0:04:14.840 --> 0:04:17.679
<v Speaker 1>com and be sure to check out the brain stuff

0:04:17.680 --> 0:04:20.159
<v Speaker 1>blog on the how stuff works dot com home page.