The idea of harnessing lightning and using the electricity to supplement our power grid has been thought up many times in the past. The difficulty has always been knowing when and where lightning will strike, capturing it, and then pushing the electricity onto the electrical grid in a controlled environment. But even if all these issues could be addressed, would it still be worthwhile to try and harness the power of a thunderstorm?
There’s no question thunderstorms generate a tremendous amount of electricity. A typical lightning bolt produces about 10,000 amps but some bolts, such as the one that struck the Apollo spacecraft upon liftoff in the 60’s, have measured well over 100,000 amps. When you convert a lightning bolt into watts, the result is a pretty larger number. But when you convert the lightning into kilowatt-hours and compare it to how much electricity the average home uses, it’s rather insignificant. When compared against a large city, it’s unnoticeable.
Even though the average lightning bolt contains about 250 kilowatt-hours of electricity, the average house uses anywhere from 500 kilowatt-hours to 1500 kilowatt-hours of electricity per month. So one lightning bolt won’t even power the most energy conservative home for half a month. Another way to look at it is, each house would need at least 2 to 4 lightning strikes per month to balance out the electricity they use. Now imagine how many lightning strikes would be needed for a whole neighborhood, small town, or a large city such as New York or Los Angeles! There are also a few technical challenges with trying to harness and use the electricity generated by a lightning bolt.
The electricity itself being one of them. Due to its high voltage and current, lightning is responsible for many power outages when it strikes power lines or transformers sending a huge amount of electricity onto the grid in an uncontrolled fashion. Harnessing lightning and releasing it in a controlled environment is difficult. One would need to come up with a system that could temporarily store the massive amount of electricity, perhaps in huge bank of capacitors and/or batteries capable of an extremely quick charge, and then slowly push the charge in a controlled release onto the power grid so as not to cause a large power surge.
While the technological advances of today’s capacitors allow them to store huge amounts of electricity, most aren’t charged in about 0.2 msec, the time it takes for a lightning bolt to deliver its 1,000,000 kilo-volts of electricity. Conversely, these large capacitors are usually charged slowly and then quickly discharged in specialized applications (particle accelerators, lasers, rail guns, etc).
Lastly, capturing the lightning presents its own difficulties. Knowing when and where a lighting bolt is going to strike is in many cases random. Lightning doesn’t know at 50,000 feet what object it is going to strike on the ground. Therefore, positioning collection towers is kind of like playing darts blindfolded. One could scatter a bunch of 500 foot towers all over the countryside, but that doesn’t guarantee a lightning bolt is going to hit it. But if one were to try, Florida would be the most likely location for such a lightning farm. Florida averages the most lightning strikes each year with about 10 strikes per kilometer per year. So, if you have a bunch of towers set up in a 1 kilometer area and these towers were able to attract all 10 of the lightning strikes for the entire year, you would produce enough electricity to power 2 homes for a month!
It’s simply not economical to build the infrastructure required to capture a lightning bolt to power our homes, which is why no company has ever successfully commercialize lightning as a source of electricity.