Capacitor to store lightning?

Discussion in 'General Science & Technology' started by cato, Sep 21, 2004.

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  1. Nasor Valued Senior Member

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    Uh...no. The electrical energy that could be harvested from the average lightening bolt would be enough to power a single lightbulb for a couple of hours. You certainly aren't going to be able to disconnect your office from the electrical grid. The energy simply isn't there.

    Edit: Although you will often see ridiculously huge numbers thrown around for the amount of energy in a lightening bolt, it's important to realize that these numbers are usually generated by considering the power output of an entire 3-4 mile length of the bolt. Your lightening-collecting tower is probably not going to be 4 miles high. Perhaps you could float a cable with a balloon or something, but I'm not sure you could make a cable thick enough to not get vaporized by the hundreds of kiloamps of current.
     
    Last edited: Mar 24, 2010
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  3. MacGyver1968 Fixin' Shit that Ain't Broke Valued Senior Member

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    What I'm still wondering....where is there a place on Earth where lightning strikes a given location often enough to bother to collect it? It would be alot more productive to take those same resources and use solar panels or windmills, and a shitload safer.
     
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  5. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    To Beny F:

    Do you understand that voltage is not energy? (You speak in your posts as if you do not.)

    Storing the same energy in lower voltage capacitors is usually cheaper than in high voltage capacitors.

    The energy in a capacitor is QV/2 or (CV^2)/2

    --------Some one asked about how to increase DC voltages:
    (1) one way is to convert them to AC and use a transformer to step voltage up and then rectify the AC back o DC, losing about 15 to 20% of the energy in the process, typically.

    (2) a second way, commonly used when weight is important as it avoids the the transformer, is to charge many capacitors in parallel (say 10 for a 10 to 1 step up) and then rewire them into a series string. The "rewiring" is typically done with optically switched transistors. There is an obvious switch break down difficulty with the highest voltage capacitor in the series sting as at times it is at V (in the parallel connections) and at other times at 10V. -Optically switched transistors can avoid break down to the switching circuits.
     
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  7. BennyF Registered Senior Member

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    Once again, I thank all who have posted constructively.

    Voltage is, of course, not energy. It is a measuring unit for the electrical energy that I hope to collect from lightning, store, and use.

    Billy, your ideas on how to increase DC voltages is interesting, and no, I won't tell you my circuit designs, due to the restrictions that are imposed on all who wish to make an application to the US Patent Office. These are statutory restrictions, and I will not violate them.

    MacGyver, there are lots of places on the earth, and even lots of places in the US where electricity can be collected in large enough numbers to make it worthwhile. As I said, the voltage can be multiplied, and as I also said, this fact drives the economics heavily in my favor. Yes, solar panels generate electricity, but they're currently not very efficient. Windmills also generate electricity, but they catch birds, bats, and bugs, requiring maintenance which reduces the potential profit margin for any company that owns them.

    Read-Only, please explain why you think the hydrogen economy is dead. In my humble opinion, it's waiting for somebody to show that he can supply large quantities of it, which I can and will do, once the red tape is cut, the equipment is bought and tested, and soon after the tens of billions of volts of electrical energy have been fed into an electrolyzer, a few volts at a time (yes, I know how to do this efficiently).

    Nasor, you said this:

    "The electrical energy that could be harvested from the average lightening bolt would be enough to power a single lightbulb for a couple of hours. You certainly aren't going to be able to disconnect your office from the electrical grid. The energy simply isn't there."

    I know something you don't, and you'll have to wait until my patent application is approved (approx. two years from now) before you find out how to generate tens of billions of volts (of electrical energy) from a single lightning bolt.



    To all: Once the voltage has been drained from my energy storage system, it can and will be used again when the next electrical storm happens.

    "Genius is ten percent inspiration, ninety percent perspiration."
    - Thomas Alva Edison, holder of the world's record for the most number of US Patents given to a single human being

    Benny F (a pseudonym)
     
  8. MacGyver1968 Fixin' Shit that Ain't Broke Valued Senior Member

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    I'm not asking for you to show your circuit design, but could you please elaborate on this "Voltage Multiplier"? V=IR. You can increase the voltage, at the cost of current, or vise versa, but the sum power stays the same. Are you claiming you can somehow "create" voltage?
     
  9. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    I am not interested in your circuit design because:

    First the voltage multiplier idea is not my idea. - They were used in space craft built at APL/JHU, where I worked 30 years ago and already then old established art to generate with little weight higher voltage than the primary batteries.

    Secondly judging from your confusion between voltage and energy in your posts, you are not well enough informed in physics or electronics to know anything new of interest (or even decades old technology).

    Thirdly, you are also miss informed about patent law. You can disclose your invention without jeopardy provided you can both establish / prove the earlier date of conceptions (A well sealed registered letter sent to yourself, which remains unopened is a common way.) AND do file a claim in less than one year from the date of public disclosure.

    PS you do not "store voltage", only energy. Just as you do not store water pressure. There are quite close parallels between water pressure and voltage and between water flow and current. Perhaps with your level of understanding you should first try to understand them and why one does not store water pressure.

    BTW you do not electrolyze water by feeding a few volts into it at a time. ONLY passing CURRENT thru the water PRODUCES HYDROGEN AND OXYGEN.
     
    Last edited by a moderator: Mar 25, 2010
  10. Nasor Valued Senior Member

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    I don't understand what you mean here. First you say (correctly) that voltage is not energy, then in the very next sentence you say (incorrectly) that it's a unit of electrical energy. If you want to talk about energy (electrical or otherwise), you should use the units of joules.
    It doesn't matter what you do with the voltage, you can't magically create energy from nothing. You can't extract more energy from the lightening bolt than is present in the lightening bolt. A new 9 volt battery has about 15 kilojoules in it. You could easily use various methods to increase the voltage from it up to hundreds or even thousands of volts, but that won't allow you to get more than 15 kilojoules out of it, because that's all the energy in the battery.

    No offense, BennyF, but you don't seem to know very much about electricity or physics. I fear that this will make it very difficult for you to get a patent, since your patent application will probably be read by an electrical engineer or physicist, who will probably be as confused about what you're trying to communicate I am...
     
  11. BennyF Registered Senior Member

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    MacGyver, I will not elaborate on my voltage multiplier. It's part of what I must keep hidden from the public if I want to obtain a patent.:shrug: Trust me that the voltage levels of the stored electrical energy, will be many times the voltage levels of the original lightning bolt. Yes, I'm aware of Ohm's law, in all three versions of it, expressed in terms of voltage, current, and resistance. I'm not a law-breaker. I just wish to keep some things hidden until after the US Government approves my patent application.

    Nasor, what I said was that voltage is a measuring unit of the electrical energy. So is current. Both are ways of measuring electrical properties of the electrical energy in lightning and other sources of electricity. Satisfied?

    One more thing, Nasor, "lightening" is what happens when you pour milk in your coffee. That's twice I've seen you misspell the word, and you're criticizing me for not being exact with physics terms?

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    Billy, I've seen enough surprises in courtrooms to know better than to divulge potentially important circuit design prior to a patent issuance. Patent infringement is pretty common I understand, and the side that wins is not the side with the most righteousness, it's the side with the best lawyers, so I have to do what I can to protect my own interests now, before the patent gets issued.

    Also, Billy, I know that current is necessary to electrolyze water, but the biggest factor in an efficient endothermal reaction is the REGULATION of the voltage (as opposed to the regulation of the current). That's why I wrote that the voltage would be fed "a few volts at a time".

    The exact number of volts necessary for maximum efficiency depends on the catalyst, and as I've said, this is the subject of ongoing research. I've seen (public domain) hydride research involving two-element materials, and I've seen newer research (also public domain) involving compounds of three elements. Each catalyst material requires a different voltage level for maximum efficiency.




    Look, I know that both voltage and current are in high amounts in a typical lightning bolt, and this is one reason why any person who wants to increase the US energy supply should be looking into using lightning to supply electricity. Once again, my collection, storage, and electricity-usage equipment is not complicated, and I am still amazed that nobody has figured it out earlier.

    I'm not going to claim (in my patent application) that I've invented a perpetual motion machine, and I'm not creating energy from nothing. All I said was that the voltage amount of the stored DC electricity would be hundreds of times the voltage in the lightning bolt, or somewhere in the tens of billions of volts, given a typical 100-500Mv peak value for a typical negative lightning bolt. If you don't know how to increase voltage by numbers that have a few zeros in them, then fine. You won't see my patent application until the rest of the public sees it. I said that my collection and storage equipment was not complicated, and I'm confident that the Patent Examiners who WILL read my application WILL be able to understand it.

    I thought I could give the energy industry a bit of hope, but it seems all anyone wants to do is to get a look inside my briefcase.

    One more time. I know how to store tens of billions of volts of electricity, using a single lightning bolt as my source. I know how to convert DC electricity into AC electricity. I know that tens of billions of volts is more than what many offices require for their office equipment, heat, air conditioning, and lights. I know how to take tens of billions of DC volts that I've stored and use some of it (as AC electricity) for my office needs. And finally, I know how to take the rest of my stored DC electricity and feed THAT, with the voltage regulation that is needed for maximum efficiency, into an electrolyzer.

    Hello, hydrogen economy! Hello, hydrogen-powered cars! Hello, industrial fuel cells to heat buildings! Hello, low-cost oxygen for hospital and nursing home use!

    And GOOD-BYE to my local electric grid sometime after the first lightning bolt hits my collection eqipment!!

    Benny
     
  12. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    No, not quite correct. You mainly want to regulate the current density at the electrode surface. This is the "mico surface" - why porous electrode structures are used.

    The current in the electrolyte is by ions and they move thru the much more common neutral H2O. For efficiency you want the electrodes closely spaced and large or to have a low surface current density. How much voltage drop is required is mainly a result of the electrode size and design for any given rate of H2 production.

    You still have not grasped the concept of conservation of energy. Step up the voltage as much as you like and your energy will not increase -in fact some will be lost in the process.
     
    Last edited by a moderator: Mar 25, 2010
  13. DRZion Theoretical Experimentalist Valued Senior Member

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    I place my bets on ambient heat conversion and geothermal. I have worked out a method that could potentially transform every depleted oil well into a useful source of geothermal energy - there are hundreds of thousands around the world. This puts power back in the hands of the oil industry, meaning minimal resistance from lobby groups and industry. The next step is finding an alternative market for coal - maybe as a carbon source for bacteria to be used by the food industry.

    I don't know how well this would work. Lightning tries to find a path of least resistance on its way to the ground. Producing heat/work will by definition increase resistance, as far as I know in every case. So you have to offset these two - which may not be too big of a problem if you have a conductive tower 2 miles in the sky. At least thats how I understand it. :shrug:

    I encourage you to keep up your work! I have faith in amateur/independent science and I think the most clever solutions will come from these people since they do not think within the paradigms set up by the mainstream scientific community.
     
    Last edited: Mar 26, 2010
  14. Nasor Valued Senior Member

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    I'm sorry, but you are simply wrong about this. Voltage is not a unit of electrical energy. Neither is current.
    It is certainly true that voltage and current are properties of electricity. But that's not the same as being a unit of electrical energy.
    I freely admit that I'm bad at spelling, which will probably be a problem for me if I ever want a job as an editor. You, on the other hand, are apparently good at spelling but bad at physics.

    You still have not addressed my point that there simply isn't enough energy in lightening to make collecting it worthwhile. You talk about changing the voltage of the lightning, but changing voltage won't let you change the total energy collected.
    The higher the voltage, the less efficient the process. The best current catalysts allow water to be split with just 1.29 volts, which is very close to theoretically perfect efficiency.
    Given your demonstrated inability to use basic physics terms correctly, I have my doubts about that...
    And you are still using the term "voltage" as if it were a unit of energy

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    Who cares about voltage? Okay, I'll grant you that there's probably some minimum voltage necessary to operate your office equipment, but that's not really relevant since a simple transformer can easily change the voltage from whatever electrical source supplies your office to the necessary voltage for the specific device you want to power. Changing the voltage of electricity is easy, and there are many, many ways to do it. The issue is energy. Changing the voltage of the electricity coming out of a power source does not change the amount of energy that can be extracted from the power source, and lightning isn't going to give you enough energy.

    Please explain what you think you will gain by increasing the voltage to billions of volts. Your office equipment doesn't run on billions of volts, it runs on somewhere between 1.5 V and 220 V. Electrolysis with an efficient catalyst only takes about 1.3 V. So what's the advantage of stepping it up to billions of volts, only to step it back down again before feeding it into an appliance? While explaining, please remember that changing the voltage of the electricity will not allow you to change the total amount of energy present.
     
  15. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    1 farad worth of storage in a tiny Aerogel capacitor. These are the latest in high-density power capacitors. 2.5 volts.


    These cost $5 (The capacitor, not the m and m)
    How much would a supercapacitor which could store the energy from a lightning bolt cost? And how big would it have to be?

    The average bolt of negative lightning carries an electric current of 30 kiloamperes (kA), and transfers a charge of five coulombs and 500 MJ of energy.
    From Wiki.


    You'd need to scale down the cost, because it would be on a much larger scale.
    But let's say it was one percent of the total cost.
    Anyone good at sums?
     
    Last edited: Mar 26, 2010
  16. Nasor Valued Senior Member

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    1 farad at 2.5 volts = 1.25 J, so if you want to store 500 MJ you would need about 400 million such capacitors. But that's probably not a good metric for figuring out how much it would cost, because for something like this you would probably use a much small number of much larger capacitors. I don't think you can scale the price easily.

    The real problem is the 500 MJ figure. That might be right for the initial electrostatic potential energy of the entire cloud/ground system, but a huge chunk of that is going to be used up creating the initial ionization path between the cloud and ground (it takes a LOT of energy to ionize a 1 cm column of air that's 3 or 4 miles long), or other sources of inefficiency. The actual electrical energy in the average bolt that is available to be harvested is only on the order of a few MJ. That's the key point that BennyF keeps dodging. He talks about increasing the voltage, as if that would somehow increase the energy available, but unless he has a way to magically get more energy out of his lightning collection device than the lightening puts into it, he isn't going to capture very much energy.

    Edit: For comparison, a kilowatt hour of electricity costs about 9 cents on average in the US, and is equal to 3.6 MJ. Given that, one would expect the tower to produce something like 5-15 cents worth of energy every time it's hit by lightning (assuming you can capture most of it). For comparison, a 1 m^2 solar panel could collect that much energy in 3 or 4 hours on the average sunny day. So the tower would need to be hit by lightening an average of about 4 times per day to equal the energy collection of a single 1 m^2 solar panel.

    Edit again: Fixed calculation typo.
     
    Last edited: Mar 26, 2010
  17. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    That is quite impressive. The capacitor stored energy E = CV/2 so you have 1.25 joules stored at the rated voltage 2.5V. To do this with very high voltage and much lower C is very much more expensive.

    For example to store 1.25J at 2.5 million volts you need a one microfarad capacitor RATED FOR 2.5e6 Volts.

    Ideally you could keep the total plate area the same / unchanged and make the separation between the plates a million times greater to keep the same internal electric field in the dielectric of the capacitor (still just safely below the dielectric breakdown field strength). A million times greater separation between the plates would correspond to the needed one microfarad capacitor.

    Thus the capacitor would be much larger - with a million times more volume, needing a million times more dielectric and cost approximate a 1,000,000 times more yet still only store the same energy*

    SUMMARY: By going to a high voltage storage design, of one million (or more) volts BennyF is forcing his system to be about a million (or more) times more expensive per unit of energy stored!

    BennyF knows very little physics, but perhaps he can follow / understand as I have explained this to him in a numerical illustration.


    PS it worth noting that the M&M stores much more energy than the capacitor can. I am to lazy to search for the sugar content of an M&M and calculate but I would be confident that the M&M is storing at least 1,000 times more energy than the fully charged capacitor. Chemical energy storage is what is required for a practical car. Thus I am confident that the talk "supper capacitors" for primary energy storage is nonsense - They may have a use as regenerative braking energy storage, but I doubt even that.
    ----------------------
    *Actually it is worse than that because it is impossible to make the thick dielectric separator between the plates perfectly uniform. I.e. some regions will have a lower dielectric constant than others. In those regions the internal electric field will be greater – closer to the dielectric breakdown field strength. To reduce the field in these regions so it too is safely below breakdown field strength, the spacing between the plate must be MORE than a million times greater. This then makes the value of C less than one microfarad.

    To help BennyF follow, I will continue with a numerical example. I.e. assume there is a 10% variation in the internal dielectric constant. Then the spacing between the plate must be 1,100,000 times greater to avoid breakdown, and to compensate for the corresponding reduction in capacitance the plate area must be 10% larger. This makes an additional 20% increase in the dielectric volume and cost.

    But don't be discouraged BennyF. Hold fast to your ignorance as DRZion encourages:
     
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  18. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    Yes, given that the figures are all correct, there is surprisingly little energy in a lightning bolt.
    Or to put it another way, a surprisingly large amount of energy in 1 KWH.
     
  19. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Yes the technician who assisted me at work recovered his roof with new shingles.

    He spent the entire first day repeatedly climbing a ladder with a heavy pack of shingles to get them all onto top of his house. Exhausted that eve after dinner he decided to compute how much work he had done. I forget the exact answer but it was about one cent worth of electrical energy. (Much less than 1KWH)
     
  20. Nasor Valued Senior Member

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    Well, there's certainly a lot of energy expended in the creation of the bolt - as the wiki page says, hundreds of MJ or more. The problem is that so much of it is already expended by the time it reaches the ground. But even if you could capture all 500 MJ that goes into making a bolt, that would be something like $12 worth of electricity. How many times would you expect it to be hit in a year?
     
  21. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    Here's a map showing the density of lightning strikes world wide, per square km .
    Even if you captured every lightning strike in 1 square km of Florida,which in the US is particularly lightning prone, you would only capture about 40 per year.
    The Congo is the world's best place for lightning at 70 per Km squared.

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    from http://geology.com/articles/lightning-map.shtml
     
    Last edited: Mar 26, 2010
  22. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    Another way to quickly understand, without post 54's physics of why, how stupid is BennyF’s idea of storing energy via high voltage is to make a series string of one million of those $5, one farad, 2.5V rated capacitors seen in post 53 photo. That series string is now a one microfarad capacitor rated for 2.5e6 volts and can store the same 1.25Joues, but now at 2.5 million volts.

    SUMMARY: Again as shown in post 54, it is a million times more expensive to store the same energy if the storage voltage is a million times greater* I.e. instead of $5 to store 1.25J you will spend five million dollars!

    -------------------
    *Again when one takes practical factors into consideration, at least one of the million capacitors in the series string will either (1) have less than one Farad (and thus have more than 2.5 Volts across it) and break down. OR (2) have less perfectly constructed dielectric space and thus not be a 2.5V capacitor. So in practice you will need more than a million units in series to have a sting rated for 2.5 million volts.

    PS if BennyF submits his ideas to the USPTO I think he should attached a warning so that the inspector does not die laughing.
     
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  23. MacGyver1968 Fixin' Shit that Ain't Broke Valued Senior Member

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    I'm sure you'd be using caps that looked more like this:

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    The highest voltage cap I could find topped out at 20kV...although the capacitance was not listed.

    I still don't understand why you would want to step up the voltage of the incoming bolt. High voltage is really hard to work with, as you have problems with arcing. Seems to me, you would want to break up that large input voltage into many branches of a lower, easier to use voltage that components are actually rated for...using some sort of voltage divider. Eventually, you would have to get the voltage to a level low enough to charge batteries. Caps are far to leaky to hold the current for any long period of time.
     
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