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Could lightning discharges be harvested and stored in supercapacitor banks? Could supercapacitors withstand and collect lightning?

Lightning usually lasts for about 10 micro seconds and reaches potentials of hundred thousand volts. However, the energy levels of lightning are quite high: Several million Joules of energy.

If lightning harvesting is not practical on ground level, could aeroplanes benefit from lightning harvesters to collect electricity?

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  • \$\begingroup\$ Supercapacitors have even lower voltage ratings than normal caps and a lightning bolt is very very high voltage. \$\endgroup\$ – DKNguyen Jun 28 at 14:18
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    \$\begingroup\$ You should do some research! Hints: 1) what voltages and currents are involved with lightning, realize that to make a 10 mm spark, about 30 thousand volts are needed. Now think about the distance between a cloud and the earth 2) Is lightning harvested at all anywhere in the world? 3) what voltages do supercapacitors work on? Find some images using google, the maximum voltage is always printed on the device. \$\endgroup\$ – Bimpelrekkie Jun 28 at 14:21
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    \$\begingroup\$ Even if you could, would there be any point? You'd have to set up an expensive lightning-attracting structure and an expensive capacitor bank, and get maybe a few dozen strikes a year. \$\endgroup\$ – Hearth Jun 28 at 14:27
  • \$\begingroup\$ NO . Even Faraday, Coulomb, Tesla and Benjamin. Franklin et al, tried and failed. The problem is 1us storage inductance and breakdown Voltage @1million bolts and extreme low voltage-ultra caps have significant losses and leakage currents. Rl/ESR is a physical limitation. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jun 28 at 17:04
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No, supercapacitors could not withstand lightning. Very few things can, actually. You're dealing with millions of volts here; supercapacitors are usually rated for less than three volts, and even the highest-rated capacitors on the general market are rated for a few tens of kilovolts.

Additionally, there really wouldn't be any point in this, for the same reason it's not practical to generate energy from the wind in a hurricane: you're relying on an inherently random event occurring in a specific location where you've set up your infrastructure. Lightning happens more often than hurricanes, sure, but consider the cost of setting up a lightning-attracting structure (expensive) and a massive bank of capacitors (very expensive), and the buck converter to get that into a usable form (also very expensive), only to get maybe a few dozen lightning strikes a year.

While trying to find information on how much energy a lightning strike contains, I found that wikipedia actually has an article specifically on this topic. It seems there has actually been some research in this direction with, surprisingly, some success in laboratory conditions, but not anything too promising. Stick with solar power.

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    \$\begingroup\$ Fun fact: The energy "released" in a hurricane in tens of minutes is on the same order of a nuclear weapon, and hurricanes last a lot longer. \$\endgroup\$ – DKNguyen Jun 28 at 14:51

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