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Comment by dole

20 hours ago

This [1] article claims that the electricity from 115 strikes could power the entire US grid for a year, but it's surely napkin math. Awesome tech, though!

[1] https://www.treehugger.com/how-much-energy-is-in-lightning-8...

Apparently a single lightning strike contains the equivalent of about 40 gallons of gasoline. It’s very powerful but not that significant on the scale of a whole city.

In fact a quick back of the napkin math suggests it would only power a city of a million people for half a second.

https://en.m.wikipedia.org/wiki/Harvesting_lightning_energy

  • This comment made me wonder about the idea of harvesting lightning as a power source. Obviously it’s incredibly challenging, but I wondered if we had magic sci-fi technology that allowed it, how useful would it be?

    Back of the napkin math suggests that even with theoretically perfect prediction, capture, storage and distribution you’d still get at best ~1% of the US’ energy through lightning capture.

  • I wonder what the average property damage is per strike. And if forcing lightning reduces or changes storm power. Maybe for preventative reasons you put them outside of towns and such.

Secondary school physics teacher here: The article is conflating power (watt or joule per second) and energy (joule or kilowatt-hour), so any claim they make is nonsense and the article shouldn't be taken seriously. My students make the same mistake all the time but they don't get to publish it :-)

Power is energy per time unit (thus: energy = power x time), so while the power of a lightning strike is very high (~10GW), the overall energy isn't because it only lasts for a very short duration (apparently the duration of a lightning event is hard to define, [1] says about 0,5 seconds, other places mention much shorter durations, ~10us). So if that 10GW lasts for 0,5 seconds, the total energy is 1,4MWh, which is 1/6 to 1/10 of the electrical energy an average American household consumes in a year[2].

[1] https://amt.copernicus.org/articles/16/547/2023/ [2] https://www.eia.gov/energyexplained/use-of-energy/electricit...

that article does not make that claim