Science Buddies: "Ask an Expert"

Hey,

I have a simple idea for capturing the energy of lightning and use it but don't know if it's possible or not. So' I need some suggestions. However, my idea is, to store the electricity of a lightning bolt via high rods in a combination of capacitors in series (making the effective voltage high). Then we'll have to reconnect the capacitors in parallel for a lower output (opposite to particle accelerators). The energy thus captured will be too small to supply the grid but we can use it through inverter system to power up one house or one industry for several days or weeks. I have made a small scale model and successfully captured 220v for split of a sec and lit up a led for several mins with absolute perfection of my calculations. Please let me know the challenges regarding this or whether it's feasible. I googled it for a long time but found the idea never imagined by anyone.

Thanks...

If a very simple idea hasn't been done already, then its implementation is usually horribly complicated or not cost effective.

One way to think of a lightning strike is a dielectric strength break down. The voltage differential between something on the earth and something in the sky or between two things in the sky is sufficient to create an ionized conduction path.

How could you expect lightning to choose a path through your apparatus rather than some alternative?

Lightning chooses the lowest impedance paths available at the lowest dielectric break down voltage.
If your capacitor experiences a dielectric break down, it won't store any energy until the voltage drops well below the break down voltage to the point where the dielectic can self heal (assuming that is possible). If your capacitor doesn't experience a dielectric break down, then very little current will be flowing through it and the energy from any lighning strike in the area will bypass your apparatus.

Even if you could solve that dilemma, you have a cost benefit problem. There are very few places on the earth that lightning strikes multiple times a year. Even if you were able to choose use one of them, how much energy could you expect to capture per year and at what cost?

Hello zafe,

Your idea makes sense, and there is a large amount of energy that might be caught. But Craig's comments also make sense--that there are many engineering challenges to be overcome.

I think the biggest problem is that the conditions for capturing a lightning strike don't occur at any given place very often. The expensive equipment would sit idle over 99% of the time. Capacitors large enough to store for "days or weeks" would be difficult and expensive to arrange.

WW

Thanks Craig.......That's precisely what I wanted to know..