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Lightning Arrestor

06/11/2010 4:09 AM

we knw that lightning arrestor protects the device from damaging due to lightning..... my question is that where does the large amount of current go and why cant we make it as a storage device rather than juz arrester???? if not what are the problems in storing the energy coming from lightning?

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Anonymous Poster
#1

Re: Lightning Arrestor

06/11/2010 7:57 AM

The large amount of current goes to the zero potential i.e. earth, We can not store the energy of lightning because the voltage produced by lightning is very high voltage and storation and proction is very diffcult.

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#2

Re: Lightning Arrestor

06/11/2010 10:04 PM

You have to undertsand the phenomenon of Lightning first. Lightning is discharge of energy stored in the cloud formations abovehead to earth. Even without a lightning arrestor the lightning stroke will find its path to earth either thro the atomosphere (have you noticed the stepped leader - a flash of white light during lightning?) or thro any structure that comes in its path. The huge discharge current would cause damage to the structures if the lightning stroke finds a path thro them. So, we provide a low resistance path for the stroke to find its path to earth. And, that low-resistance device is called "Lightning Arrestor". It diverts the lightning stroke safely to earth rather than thro any other costly & important structure. So, whether thro the LA or thro any other means lightning current goes to (natural) earth only.

The problem with storing lightning energy is both the magnitude and duration. As already posted, there is no device found so far to "receive" and store the huge magnitude of lightning energy. Also, how do yoy capture such huge energy in, say, micro-seconds of the stroke duration?

But, that would be an innovative idea to store the lightning energy. If only we could .......

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#3
In reply to #2

Re: Lightning Arrestor

06/11/2010 10:14 PM

hmmmmmmm..... fine lets try to find some device that can store the lightning energy so that a large amount of energy can b utilised.........lets think

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#4
In reply to #3

Re: Lightning Arrestor

06/11/2010 11:29 PM

Welcome to this forum young lady, and i hope you will have a great time here.

Coming to lightning, Tesla is my favourite on this and other subjects.

Please study and let us know what you find...

cheers.

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#5
In reply to #4

Re: Lightning Arrestor

06/12/2010 12:18 AM

hi the link is very useful..... and i went thro that... from this we can infer that capacitors are good for instantaneous charging.....and cud u say wat is ur point of view??? but i dont hav any idea abt using it practicaly.....pls let me knw abt it....

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#6
In reply to #5

Re: Lightning Arrestor

06/12/2010 12:29 AM
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#13
In reply to #4

Re: Lightning Arrestor

06/12/2010 6:27 AM

hi,

Is the lightning arrester reqd. for every building?

i am asking this question because i live in pune [India] i have built own Wind mill and going to install it within 10- 15 days. The height of the building is @45 feet . and wind mill is @ 10 feet height.

So is it necessary to protect from lightning and how?

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#18
In reply to #2

Re: Lightning Arrestor

06/12/2010 10:02 AM

Yes, exactly. Certainly lightning energy could be harnessed, but the devil is in the details.

For our purposes, the lightning stroke is just a very high current, say 100kA, for a very short time, say 50us. So let's get specific.

If we charge a capacitor with that current, it has to be a rather serious pulse capacitor. Like this capacitor, one of four I purchased to make a quarter shrinker (someday when I have time). It's a Maxwell p/n 33504, rated at 100 uF and 10 kV. It weighs 160 pounds, and its energy storage capacity is E = 0.5 C V^2 = 5 kJ. This is a serious pulse capacitor, with a peak pulse current rating of 150kA, high enough to handle most lightning strikes.

If we present this capacitor with a 100kA current for the entire 50us stroke, it's voltage would rise to V= i t / C = 50kV. Oops, it's only rated for 10kV. Although we know the current doesn't stay at its peak value the entire time, it seems likely that we'd want to parallel two of these caps, and add a say 250kA capable over-voltage discharge path to handle extreme events and protect the capacitors.

For simplicity, let's assume the stroke fills our two 100uF capacitors with 10kV, or 10kJ of energy. The lightning strike is basically a current source, whatever voltage we present on the receiving node, the current will not diminish. The "compliance range" of the strike is very high, say 100MV, so our puny 10kV has used only 0.01% of its capability.

Let's say we're very ambitious, and have gotten a fat $1M gov't grant, and we buy 200 of these blokes. We make a bank of 100 pairs in series, along with 100 over-voltage protectors. Arguable, we now have a big enough pulse-capacitor bank to use up 1% of the lightning strike's voltage capability.

We spend the rest of our $1M on a 1-mega-volt dc to 120Vac power converter.

OK, so now we have of 1MJ of stored energy ready for use. What are we going to get from it? My computer takes about 100W. Aha, each time a strike happens to hit my collecting point, and fills my $1M capacitor bank with nature's free energy, I can run my computer for t = E / P = 10^4 seconds, or about 3 hours. Thereby saving me 0.3kW-hr, or about 5 cents on my electric bill.

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#21
In reply to #18

Re: Lightning Arrestor

06/12/2010 2:57 PM

So basically if we could charge a capacitor as big as a house you would only recover barely enough energy to make a decent cuppa.

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#27
In reply to #18

Re: Lightning Arrestor

06/12/2010 10:33 PM

You got a GA from me!! I did the math about 10 times, on paper, using all the various values I could find from reputable sources, and didn't post it because I felt sure my numbers had to be flawed. But they match. If someone can prove that the math is bad, I'd LIKE to be corrected on it. OTOH, you've actually used some fairly conservative numbers, according to several University sources, and the US NOAA, that I've checked. You weren't trying, I suspect, to portray worst case, but if the "perfect" lightning storm hit us, even with that ambitious rig, there would still not be enough left of us and it to figure out what went wrong. And therein lies ANOTHER problem. Engineers, in converting theory to practice, HAVE to design for worst case, because, especially in cases where we're already working with explosive forces, the worst case is magnitudes worse, and the resulting calamity is magnitudes larger.

Witness the current Gulf leakage/BP oil problem. Huge resource of oil, but a WHOPPER when it fails.

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#30
In reply to #27

Re: Lightning Arrestor

06/13/2010 7:09 AM

Thanks for the GA!

Yes of course we engineers have to design for worst-case conditions. I did say to add, "a 250kA capable over-voltage discharge path to handle extreme events and protect the capacitors." These are actually fairly simple spark-gap structures, and quite practical to rely on. I've examined a set of them meant to protect $M-dollar HV Klystron tubes at a nearby accelerator center, and they consisted of 2 to 3-inch steel balls spaced about a half-inch to an inch apart, with positioning clamps to adjust the breakdown voltage. According to a NASA study on the probability of extreme events, 90 to 95% of the strikes would not activate our lightning protection device, and I think it should be able to safely handle the rest of what nature could throw at it. A 250kA strike is shown to be below the 0.5% probability level, and a 500kA strike at 0.01%. A 250kA-rated part might have to be replaced after such a strike.

[Hah, I was just a victim of a power failure (not a lightning strike), and thought my comment above, all ready to send, was lost. But no, CR4 remembered and put me right back where I was, comment and all. Nice.]

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#31
In reply to #30

Re: Lightning Arrestor

06/13/2010 8:19 PM

I did see that "overdrive" protection. I was really attempting to springboard off your good work to explain further why we don't try to store lightning, and what we'd face if we tried to do so, other than the fact that there just ain't all that much power available. Its just that what there is arrives so cotton-picking fast!

I had to design a lightning protection scheme for an exterior PA system, used on an Air Force Station in Colorado Springs, more years ago than I want to say, and a company called Lightning Elimination Associates came up with some basic MOV/Carbon Block spark gaps, which cost us about $3US apiece, in thousands (we stocked the base supply with enough of them to allow for 200 lost per strike, with 5 strikes per year, which might sound like a lot, but that area gets an incredible number, second in the US only to Homestead, FL, of cloud-to-ground strikes in any year. It wasn't excessive.), and the first time we had a storm, which was the day the installation was finished, they worked perfectly, snubbing the damage to 3 $15 speakers, about 20 of the snubbers (because of a lot of surge-coupling due to the ground charge), and about 70' of cable which had supplied the speakers. Everything else, including the AF folks working on the PA Amp racks came through unscathed. But it was a spectacular sight, for sure!

Lightning is fascinating, but that is because of the sheer force of delivery in such a short period of time. It surely LOOKS like it ought to be more power than it is.

And that, along with a lot of other physical events we can observe regularly, is proof enough of God's power, to me! But that's another discussion entirely.

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Anonymous Poster
#7

Re: Lightning Arrestor

06/12/2010 4:53 AM

Hi Poor Nima ,

I was thinking about this too at times . A problem that I see is that a normal lightening rod is a path of very little resistance for the current to go to earth . During a lightning storm lightning is attracted to the lightning rod because of this low resistance . If you introduce a load onto that system you make that resistance much greater which doesn't attract the lightning any more .

Here's an idea . Lightning also strikes power lines from time to time , most power lines have some sort of self resetting fuse which protects more delicate components along the line . Like transformers or your TV or computer ! I'm not exactly sure how it works though .

A device like this on your lightning rod would keep the low resistance path to be kept intact but MAYBE divert the electricity to one side for potential storage at the right time ?

Just brain storming a bit here !

Also would the electrolysis of water into Hydrogen and oxygen be possible from a lightning strike ? It would have to be sized appropriately , but should be able to cope with variations in voltage and current (Big question marks ???? ) .

Maybe you'd just have a big explosion with the electrolysis idea ? ( Big Bang ! ) (theory )

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#10
In reply to #7

Re: Lightning Arrestor

06/12/2010 5:50 AM

hi

if the electrolysis of water is possible from lightning then the sea water should be splitted..... is that happening?

i dont hav any abt it......

cud u briefly explain it?

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#25
In reply to #7

Re: Lightning Arrestor

06/12/2010 6:46 PM

Hi Poor Nima again !

Just some more ideas re. the Lightening Catcher , I'm not electrical engineer , just crazy thinker !

I was wondering what would a transformer do in the path of the lightning rod ?

This made me think , what about a heating element in the lightning rod circuit ? To heat or vapourise water to further power a steam turbine .

Another thought , If a car with rubber tyres gets hit by lightning which can happen doesn't the charge just spread out around the shell of the car to be dissipated the next time a connection is made to the earth , such as you opening the door from the outside or putting your feet on the ground from inside the car . Or am I just doting ?

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#26
In reply to #25

Re: Lightning Arrestor

06/12/2010 7:22 PM

With regards to putting a transformer in the path of the lightning, I tell you you exactly what happens from personal experience. The transformer windings melt, and puddle up in the bottom of the transformer. I suspect if one used an oil-filled transformer, it most likely would explode...

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#41
In reply to #26

Re: Lightning Arrestor

06/17/2010 4:21 PM

But let's assume it withstands the tremendous discharge; still you can't step-down DC current.

Yahlasit

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#8

Re: Lightning Arrestor

06/12/2010 5:00 AM

Hi poor Nima again !

Was also wondering or thinking could rotational movement be produced in a special device in the process of transferring the current to ground ?

Ummmn . More ideas springing to mind , have to keeping thinking !

Bye for now !

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#12
In reply to #8

Re: Lightning Arrestor

06/12/2010 6:00 AM

hey this seems to b gud...

it is better to convert the energy rather than harnessing it.....

pls let me knw if u get idea.......

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#9

Re: Lightning Arrestor

06/12/2010 5:38 AM

the lightning current goes to earth....now abt the concept of storing n harnessing..........the concept has been in discussion for a very very long time.....the problem with storage s that lightning s very unpredictable.....since its a natural phenomenon u cant expect wen it will hit and wit what capacity it will hit.........so protection of equipments used for storing lightning energy is not guaranteed.........some scientist had suggested abt connecting a series of large capacitors in parallel such tht number of large capacitors connected in series must be equal to tht connected in parallel...... i don ve much details on it....

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#11
In reply to #9

Re: Lightning Arrestor

06/12/2010 5:56 AM

hmmmmmm

ya v can connect capacitance in series and parallel but then the no. of capacitor requied wil b more...... which wil b coslty and practicaly not aplicable.......

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#14
In reply to #11

Re: Lightning Arrestor

06/12/2010 6:47 AM

i agree tht its very expensive but once if it succeeds (0.5%),you could light mumbai for decades.................and i think in a country like india this would be an outstanding achievement.............

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#15

Re: Lightning Arrestor

06/12/2010 7:47 AM

Lightning also produces large quantities of ozone - which is present in the ozone layer surrounding the earth.

As we know, the ozone layer filters out most of the UV rays - preventing them from reaching the earth's surface.

Nature is doing such a fantastic work - free of cost.

Rajan

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#16
In reply to #15

Re: Lightning Arrestor

06/12/2010 7:59 AM

ur msg is very informative....

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#17

Re: Lightning Arrestor

06/12/2010 9:16 AM

Dear Poornima,

Some small suggestions about CR4 protocol ... hope you won't mind...

  • There is a "Rate" button on every comment. If you think an answer is good, and helps you, you can rate it "Good". It is a good way of thanking the respondent.
  • While it is no problem to understand truncated and vowel-less words like one uses in SMSs, it is better to type correctly, since this international forum has people from all over the world, and proficiency in English varies widely.
  • Do not divulge any personal data like email ID, phone number etc. It can be misused.

Dear other posters, "Poornima" is a nice feminine name, indicating full moon. Not Poor Nima, which of course means what it means Just a feeble joke, hope you don't mind.

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#20
In reply to #17

Re: Lightning Arrestor

06/12/2010 11:30 AM

hi

thanks for your explanation for my name.....

and sure i will give rating and i will not use truncated words......

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#22
In reply to #17

Re: Lightning Arrestor

06/12/2010 3:57 PM

Another point:Poorni is a homonym for an english word that has not- so- nice connotations.It would be better if she signed her full name(Poornima) instead of porni.

Such a beautiful name I would hate to see it disparaged.

HTRN

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#19

Re: Lightning Arrestor

06/12/2010 10:30 AM

Have a look at this:

http://news.nationalgeographic.com/news/2010/03/100325-presidio-texas-battery

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#23

Re: Lightning Arrestor

06/12/2010 4:02 PM

When lightning strikes a tree, it explodes because the sap is instantly converted to steam.Could we not find a way to utilize a similar effect with a very highly saline water solution and convert the strike to heat? I realize lightning is an unpredictable source, but it can be induced if conditions are right: balloons, etc.

HTRN

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#24
In reply to #23

Re: Lightning Arrestor

06/12/2010 5:38 PM

Yes of course. Bert Hickman, an expert in high-voltage high-current hi-jinks, made an interesting post on the usenet group, sci.electronics.design, about some of the appropriate electrolyte water solutions one could use. It's #14 in the s.e.d. thread here. Here's one of Bert's shrunken quarters.

But whatever scheme one employs, there's still some simple math that shows how limited the possibilities are. That's because the strike is a current source, and even tho it's as much as 100kA for a strong strike (see the calculations in my post above), it doesn't last very long, and only a limited amount of energy is available for our use. In my example, dropping a full million volts (and requiring 1MV insulation to avoid a shorting arc), only 10kJ was available and stored. It's a simple matter of I*V*t, where I and t are fixed by nature. So to capture more energy, we have to increase the V drop in our collection apparatus.

As for the tree, I can only guess what its voltage drop is during the strike, maybe more than 1MV, maybe not. If the current path is small during the strike, perhaps 10kJ is more than enough to vaporize some of its core water and super-heat the steam, to explode the tree. SFAIK, generally one doesn't see a lot of burning, just mostly a big split. For example, this picture.

But even if the tree absorbs say 50kJ (corresponding to 5MV of voltage drop), as I pointed out, that's only 25 cents worth of electricity.

Those are the sobering pieces of electronics math.

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#28
In reply to #24

Re: Lightning Arrestor

06/13/2010 1:53 AM

Your math is sound. Collection is just not economical on any current scale.

We turned several 2x4's into toothpicks with repeated strikes from a 200kV 20 kA Marx bank. You don't want to stand near a tree during a strike because if the arc doesn't get you, the wood shrapnel will.

Electromagnetic forming (and Launching!) is a lot of fun. But that looks more like a Kennedy half-dollar to me

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#29

Re: Lightning Arrestor

06/13/2010 6:56 AM

I think u have a very good point here, but in what form can the energy be stored? Is it as heat? That is also a wonderful and fantastic idea.

Factors that are considered in building an acceptable and reliable systems should include STEADY AVAILABILITY of PRODUCT to be processed.

Unlike SUN, WIND and RAIN that can be processed and stored, THUNDER STRIKE is a chanced issue that can happen only when there is a bombardment of thunder clouds. More so the point of strike is never fixed as it is completely depend on the direction of the wind.

So, I am of the opinion we let this project go for now on till we find a place were thunder strikes occur in per second chances.

Bye.

DICKSON

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#32

Re: Lightning Arrestor

06/13/2010 10:16 PM

For those of you interested in an active program to "store" lightning, I once again suggest the link in my earlier post, about a big storage battery being built in Presidio, Texas specifically for that purpose. Again, the Link is:

http://news.nationalgeographic.com/news/2010/03/100325-presidio-texas-battery

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#33
In reply to #32

Re: Lightning Arrestor

06/14/2010 1:56 AM

Suggest a re-read. This battery is intended to store utility power during normal periods and to source power (locally) during the frequent utility outages caused by lightning.

Think of it as a small scale version of pumped hydro storage or a big UPS for the region.

While this huge battery is impressive, trying to charge it in a few milliseconds with a captured lightning strike would likely cause severe damage or destruction of the system.

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#35
In reply to #32

Re: Lightning Arrestor

06/14/2010 5:25 AM

Yes, thank you for the link. I had not followed it because I'd read about this installation earlier, probably from a story in the Transmission & Distribution World newsletter.

Although the article talks about lightning as the reason for building the new Presidio battery, it's not to store energy from lightning strikes, but rather to provide temporary power after a disruption, including from lightning strikes. "The battery system will have a fast response time to address voltage fluctuations and momentary outages. And it also is designed to supply uninterrupted power for up to eight hours." Apparently the remote location of this town meant they suffered frequent and prolonged outages from various causes.

Last night I watched an interesting program about Marfa, TX, and its famous Marfa lights. It seemed that Marfa was a very remote place, but Presidio is even more remote, with "one link to U.S. electrical power, stretching some 60 miles (100 kilometers) from Marfa in the high desert to the banks of the Rio Grande."

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#44
In reply to #35

Re: Lightning Arrestor

06/18/2010 10:51 PM

hello sir...

I am very happy to have you sir...

first i dont know what is quarter shrinker........i dont know that such a research is going on....because of you i got an idea about quarter shrinker sir....and i would like you to guide me and clarify my doubts.... please sir it is my request..please spare some of your valuable time with me sir.....

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#34

Re: Lightning Arrestor

06/14/2010 2:50 AM

Lots of outstanding posts, and i for one have gained some knowledge from these.. thank you all.

As i said in my first post in this thread, i am an admirer of Tesla and have downloaded the YouTube videos starting with this one..http://www.youtube.com/watch?v=D2g9hlDVjk8

Maybe another Tesla will come along, hopefully with another, more generous, JP Morgan ???

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#36

Re: Lightning Arrestor

06/15/2010 5:03 PM

Hi Poor Nima !

Don't know if you are still around or Interested .

I don't why a lot of people around here are so dismissive of this idea .

The idea of a wild huge energy source is not new . Look at nuclear power . Enough energy to vaporise cities but can be controlled enough now to generate electricity cleanly and cheaply .

Some further thoughts about the lightning idea .

The car's metal shell and shape is known as a Faraday cage . An aircraft is similar .

I'm not sure if the full charge of a bolt of lightning strike remains surrounding the shell of the car or if it dissipates and if so how quickly ? But I'm trying to find out !

Also I see a possible mechanical way to harness the energy of the lightning bolt .
I'll be back to you . Have to think a bit more about it !

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#37
In reply to #36

Re: Lightning Arrestor

06/15/2010 8:35 PM

Moose:

Read post number 18, this thread. THERE JUST AIN'T NO HUGE AMOUNT OF POWER THERE! Do the math yourself. I did. His numbers agree. Its one pulse of about 300Whrs of energy. The only reason its so spectacular is that it is all dumped in such a short time! But its only enough energy, if you harvested ALL of it, to light a 100W bulb for three stinking, measly, hours! Its piddling, when you come right down to it. It ISN'T a "wild huge energy source". Its less power than your car battery stores, by magnitudes.

Think, man!

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#39
In reply to #37

Re: Lightning Arrestor

06/16/2010 4:42 PM

Hi

micahd02 and mjb1962853

I've read this whole thread again and I admit defeat in this lightning energy collection business .

Have to admit that the idea is completely unfeasible . But just out of curiosity I'm putting forward one last thought about the idea as if the idea was feasible .

Capture the lightning bolt using the capacitor setup or faraday cage as a temporary energy store .

Induce a secondary more controlled arc through an enclosure . The arc causes an air pressure change which is captured and used to generate electricity by more conventional means .

Just offering my thoughts here , sometimes completely crazy ideas lead on to different ideas .

Regards

Moose !

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#38
In reply to #36

Re: Lightning Arrestor

06/15/2010 9:35 PM

The "average" lightning bolt energy is approximately 500 [MJ] or 139 [kW-hr], which is about ten days (or $14.00) of "my" electricity use.

While 500 [MJ] is significant and equivalent to the energy stored in 15 [gallons] of gasoline, there is still NO PRACTICAL way to quickly capture and store that amount of "electrical" energy.

***
Some things to consider (updated):

"Average" bolt of lightning = 500,000,000 J
one stick dynamite = 2,000,000 J
one 12V lead-acid car battery = 2,000,000 J
100 W-hrs electric = 360,000 J
2000 W-hrs electric = 7,200,000 J

Approximate volume energy density comparison...

gasoline = 33,000,000 J/Liter
car battery = 800,000 J/Liter
supercapacitor (EDLC) = 80,000 J/Liter
electrolytic capacitor = 8,000 J/Liter
film capacitor = 800 J/Liter
***

One more problem:
Because of some odd (old) fire damage, I believe my home "may" have been struck by lightning (1) time in its (100) year life. The low probability of even catching a strike means the concept is not practical even WITH an ideal 100% efficient capture/storage system.

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#40
In reply to #38

Re: Lightning Arrestor

06/16/2010 6:17 PM

Opps! Sorry, I need to watch those units. Correction...

"15 [gallons] of gasoline" should be "15 [liters] of gasoline"

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#42

Re: Lightning Arrestor

06/17/2010 4:56 PM

It is possible to gain some control over when and where lightning strikes. The following is an image extracted from a study done under the auspices of the Electric Power Research Institute at a facility especially designed to study lightning in Florida. To induce lightning, they would fire wire-tethered rockets into thunder heads. Not something I would recommend trying at home...

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#43

Re: Lightning Arrestor

06/18/2010 10:46 PM

hi friends.....

it is very happy to see the response from you people......

when i posted this question i did not have even a small idea but now because of you people...... I am very much intrested to join you people in this research.....

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#45

Re: Lightning Arrestor

09/03/2010 6:32 AM

well there is a lot of brain storming going on here,thanks for all the posts which brought some sense abt lightning ,


great job guys

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