Naked Science Forum
Non Life Sciences => Technology => Topic started by: Nizzle on 25/11/2009 10:53:45
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What technical difficulties still need to be overcome to store electrical energy straight from lightning?
We can already control the place where lightning will strike by simply building a big lightning rod, but why can't we store it yet?
Aren't there mechanisms like oversized capacitors or something we can use to convert the massive amount of electricity on a short period of time to a more constant rate of electricity over a longer period of time?
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There's just not enough to bother with.
There are about 100 strikes a second and each delivers about 500MJ- about 50GW
If I bought that at the rate I pay the electricity company it would cost (at about 10p/KWhr) about £5M an hour. That's about £43B a year which is quite a lot of money. Imagine I wanted to invest in a "worldwide lightning conductor/power station".
I could expect to recover something like £43B a year from my investment and, on that basis I might be able to borrow about 10 times that much (ie at 10% interest).
That gives me about £0.5T to invest.
The trouble is I have to spread that over the entire earth.
That's about
510072000 km²
That's about £850 per square Km.
I couldn't get close to buying the land rights for that- never mind setting up horribly complex infrastructure.
I realise that you wouldn't need to buy all the land but at a rough guess if you build towers 1Km high (which is about the limit of technology) you would need to have them not much further than 1Km apart or a lot of the lightning would miss them.
The Burj tower cost about a billion dollars so you can see that the economics don't make sense.
There may be places in the world where the number of strikes per square km is high enough to make the investment worthwhile, but for the earth as a hole, it's a pipe dream.
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Thanks for explaining the financial difficulties BC.
But wasn't there a stretch of land somewhere in Mid-USA that sees a lot of thunderstorms and accompanying lightning each year? Maybe it would be worth building some "lightning plants" over there, keeping the Copenhagen Climate Conference in mind...
Now back on topic [;)]
What technical difficulties still need to be overcome to store electrical energy straight from lightning?