is it possible to harness the lightening to get electricity.
Absolutely. It's also so dangerous and unpredictable that it's useless as a concept for power generation.
Also throw in not dense or continuous enough for widespread, continuous use.
can a huge capacitor or van dee graaff generator connected to lightening protection system store a part of the electricity from lightening.
I would think that practically any method of power storage could be adapted to lightning.
“However, there are two seemingly insolvable problems in tapping the power of lightning: (1) most of the power is converted to thunder, hot air, and radio waves which cannot, at present, be recovered, leaving only a small fraction available at the (lightning) channel for immediate use or storage. And (2) it is impractical to intercept with tall towers or similar schemes any significant amount of lightning energy. For example, the total energy in a single flash, if it could be captured, would operate a single light bulb for only a few months. Since only a small fraction of the total flash is available, thousands of flashes would have to be captured during that period to power a single home.”
From “The Lightning Discharge” by Martin A. Uman, Dover Publications, 2001
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