Electric cars are a pipe dream

Discussion in 'General Science & Technology' started by Syzygys, May 20, 2010.

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

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    No other fuel than the one YOU assumed was in my tank (I have never said which of the dozen or so fuels would be there I have only calculated the tank's VOLUME.)

    For the fourth time:
     
    Last edited by a moderator: Nov 19, 2011
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  3. adoucette Caca Occurs Valued Senior Member

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    No Billy, you have not stated a SINGLE fuel that has a 3 to 1 gallon gas equivalent and is available for $1 gallon.

    Except for CNG at 3,600 psi

    Arthur
     
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  5. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    That is correct. I have only agreed that IF tank were filled with CH4, AS YOU ASSUMED, it would beat the hell out of current EV's ranges and cost only about $1 / gallon of gasoline equivalent.

    If you had only stated the part I made bold above, you would be 100% correct. I have not stated a single fuel (to be in the tank). However, recently I did list about a dozen that could be.
     
    Last edited by a moderator: Nov 19, 2011
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  7. adoucette Caca Occurs Valued Senior Member

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    More lying Billy.

    YOU put those two qualifications in the same post.

    You stated the 3 to 1 volume equivalent by using 7 gallons as the metric for your 21 gallon capacity tank and you stated the cost at below $1 per gallon.

    Here's your list:

    Methane IS natural gas and the only way to get 7 GGE is to compress it to 3,600 psi

    Propane is 1.5 to 1 GGE, but it costs nearly $3 per gallon so fails.

    Butane costs the same as Propane so it also fails the cost test.

    http://www.neb.gc.ca/clf-nsi/rnrgynfmtn/prcng/ntrlgslqd/cndnmrkt-eng.html

    Hexane is a major part of gasoline and not any less expensive than gasoline.

    The other liquids such as Gasoline and Alcohol aren't available for $1 a gallon and don't require this complex tank and so resorting to them as a suggestion of the fuel is just SILLY.

    So again Billy the ONLY fuel that meets BOTH of your conditions in that post is CNG at 3,600 psi.

    Do you really want to continue trying to say that wasn't the fuel you were assuming in that post Billy, because it really is getting funny to watch you wiggle?

    Arthur
     
  8. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    23,198
    For the 5th time:

    I was not assuming any fuel. Never have. I was doing an analysis on the fuel YOU ASSUMED , which was CH4.
     
  9. adoucette Caca Occurs Valued Senior Member

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    LOL

    Your squirming is friggin hilarious Billy.

    So let's go back to the post that started all this squirming shall we:

    http://sciforums.com/showpost.php?p=2853713&postcount=2219

    Billy asks me to apologize for THESE specific posts:

    “ Originally Posted by adoucette
    {post 2191} Billy claims he has designed a flat CNG tank that he claims is 35% more efficient than any cylinderical tank in existence ...
    All HAIL Billy, If he can't design it, Nobody Can. Arthur ”

    “ Originally Posted by adoucette
    {post 2176} Clearly Billy has no expertise in engineering or materials and the proceeding is not based on anything but wishful thinking...
    Give it up Billy, you aren't an engineer* and your poor understanding of the issues around CNG gas storage is blatantly obvious.

    Then he posts a link to a tank designed for LOW PRESSURE Propane as proof of that I was wrong.

    When pointed out that the tank shown doesn't support his assertions as the pressure is ~1/16th that of CNG, Billy spends the next umpteen posts claiming he was never assuming CNG as the fuel.

    LOL

    Hoisted on your own petard once again Billy since you were specifically asking for an apology based on my assertions about the ability of your tank to hold the pressure of CNG.

    Arthur
     
    Last edited: Nov 19, 2011
  10. billvon Valued Senior Member

    Messages:
    21,635
    You were indeed talking about CNG. That was the only fuel ever mentioned up to that point, and that's what the discussion was about.

    Your denials remind me of someone who makes a simple math error (i.e. "9 x 4 =40") then tries to get out of it by saying "but . . . but . . . I was using base 9! I never said I was using base 10! Yeah, that's the ticket. You just assumed that it was base 10. Boy are you a stupid liar."

    You made a mistake. We all do.
     
  11. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    23,198
    You said the tanks could not be built. Called it "Unobtainum" (or something like that. I am too busy to go back and get your exact word if that is not it). I showed a photo of one, to show it could be built, not to claim it would hold CH4. (The photo does not tell what is in the tank – only that it has been built.)

    I have never said what the tank would hold, but we earlier were discussing CH4 so it is reasonable that you and other might assume that would be the contents. What is false, lying, is for you to continue to say that I said it would hold CH4 at 3,600psi after I have told you about 19 times that:
    (1) I have never said what the tank hold or
    (2) What is the operational pressure limit of the tank.
    (3) That I am only doing math / geometry analysis of relative efficiency of flat tank vs. cylindrical tank.

    Billvon guessed, (incorrectly) that at 3,600psi it would explode or if made with thicker tension webs so it would not, it would be too heavy for a car to carry. Honestly - he had me worried as I too was thinking it would be useful for CH4 but I had never checked if the particular web sizes I had described could hold 3,600psi. It turned out they could if the tensile strength was 10% of the max that has been achieved.

    You see - I was not speaking of any pressure or any fuel but only about the novel geometry of compound tank with adjoining "shared walls" which is (I still think) more efficient than the conventional cylindrical tanks. The 35% more efficient claim may be before I had, at trippy's prompting added "filets" at the corners. They add to the wall mass and decrease the stored volume so do lower the efficiency.

    I am doing a very careful analysis of the geometry, which I will post (as told many posts back) in the physics forum, when it is done. My concern is and always has been with the relative efficiency of my "flat tank" vs. circular cylinder tank, which is a function of only the geometry. Why I have not been concerned with the operational pressure and what fuel is in the tank and never said anything about either.

    I defy you to find a post where I did. True when billvon said my tank would explode if it 3,600psi or Adoucette said if filled with CH4 it only had 6.7 gasoline equivalent; then I did use THEIR assumed pressures and gas to do some calculations.

    The first replying to Billvon showed his guesses were wrong. The second replying to adoucette pointed out that while true IF as adoucette assumed, it held CH4, that was only held 6.7 gallons of gasoline equivalent, it still "beat the hell" out of the current EVs in range.

    Replies to THEIR ASSUMPTIONS forced me to do calculations with THEIR values and gas fill, but that is not the same as my saying the tank would hold CH4 at 3,600psi. I have only computed the tanks volume - a geometric property of the tank. I will continue to defend that and challenge anyone to re-post my post (not a reply, where I am using CH4 or 3,600psi that OTHERS assumed) where I say what the tank pressure is or what fuel it holds.

    I don't have time (or inclination) to repeat this for the 20th time. Believe whatever you like, but you will not find a post of mine (except those two replies) where I tell either the pressure or what is in the tank. I am discussing geometry (except when forced to tell: "I did not say that" and give documentation.)

    When I finish the careful math model of the tank geometry analysis and post it in a new physic tread, I will return here, just to give a link to it.
     
    Last edited by a moderator: Nov 19, 2011
  12. adoucette Caca Occurs Valued Senior Member

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    7,829
    BS
    I said the tanks couldn't be built with today's materials at a reasonable weight to hold CNG.
    In every post and link it was clear that I was discussing CNG.
    I kept bringing up the issue of PRESSURE over and over and over.

    Which you acknowledged that you were indeed considering pressures equal to standard round CNG tanks.


    Since that was the thing we were discussing, of course it's reasonable. More than that, you acknowledged you were considering pressures of standard round cylinders.

    Because the issue is and always has been CNG storage, storage for things like Propane, butane, hexane etc is irrelevant.

    NO, it is not more efficient than a cylindrical tank.
    It is more efficient only if you are trying to fill a square or rectangular space.

    That through all of this you have not shown any evidence that your flat tank can be built to hold 3,600 psi CNG using existing materials and methods at a reasonable weight and price.

    Arthur
     
  13. Trippy ALEA IACTA EST Staff Member

    Messages:
    10,890
    I've been asked for my thoughts on this, so here goes.

    I find this problematic on several levels. The first of which is the manufacture of calcium carbide in the first place - there's a one to one stoichiometry of calcium carbide produced and carbon monixde produce, so for every kg of calcium carbide produced, you're producing 0.69 kg of carbon dioxide, then there's a 2:1 stoichiometry of acetylene burned and carbon dioxide released, so for every kg of Acetylene burned, you release 1.7kg of Carbon Dioxide, and for every kg of acetylene you produce, you need 2.5kg of calcium carbide (again, it's a 1:1 stoichiometry. The combined result of which is that if we include the carbon dioxide produced during production as well as consumption (but not taking transport into account), for every kg of acetylene consumed, you've produced 3.4 kg of carbon dioxide (assuming i've done my math right).

    Another level I find this problematic on is the properties of calcium carbide itself. Technical grade calcium carbide is only 80-85% pure, and gives off Phosphine, Ammonia, and Hydrogen sulfide when hydrolyzed. All of which not only smell ruddy awful individually, have the potential to cause serious health issues when allowed to accumulate in relatively low concentrations in a confined space (such as the interior of a car). I also find elements of the SDS problematic, because it implies that any call out to an MVA, or a vehicle fire, would require Fire Officers to attend in full SCBA equipment (especially for a vehicle fire), and use only Class D Extinguishers, or similar equipment - you can't even use Halon type equipement on it. The reason why I state that even an MVA would require attendance in full SCBA, is because as near as I can see, any incident which potentialy results in a breach of the calcium carbide storage tank, or for that matter, any failure of the cutoff mechanism to prevent the introduction of water into the tank, could result (I would go as far as saying, probably will result) in a vehicle fire, so the fire service would have to treat every MVA as if it was a fire.

    The third aspect which I find troubling is the properties of acetylene itself. The UEL for acetylene is 100%, the LEL is 2.5%, acetylene undergoes an exothermic addition reaction that can produce wonderful things such as Benzene leading to explosive spontaneous reactions at pressures in excess of 200 kPa (29 psi), so 100 psi is definitely out of the question. This is also important to consider, because it requires the consideration of what might happen in the event of a relatively minor over pressure in the system, and illustrates one of the reasons that I suggest that every MVA would have to be treated as a vehicle fire, even if one hasn't developed - because there are a substantial number of failure modes from a simple MVA that have a high probability of leading to a vehicle fire. Acetylene is stored and transported safely by disolving it in Acetone or DMF, and putting it in a tank with Agamassan. The guy who developed this method, a Nobel Laureate by the name of Gustaf Dalen was himself blinded in an Acetylene explosion. so there's three reasons that I think that the use of Calcium Carbide isn't as good as it seems at first glance.
     
  14. adoucette Caca Occurs Valued Senior Member

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    I'll take expensive flammable exploding vehicles for $500 Alex....
     
  15. Syzygys As a mother, I am telling you Valued Senior Member

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    12,671
  16. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    23,198
    " Volt will miss its sales target of 10,000 cars this year, the company said. ... Volt sales through November totaled 6,142, the company said.
    ... GM is expanding annual production to 60,000 units starting in January, ..."
    From: http://www.bloomberg.com/news/2011-...rise-2-8-as-u-s-probes-gm-plug-in-hybrid.html

    More facts from this link:
    "dealers sold 1,139 of the plug-in hybrids last month,{November}" ...{Because}... GM last month allowed dealers to sell as many as 2,300 demonstration models to retail buyers, helping spur a 2.8 percent increase from October ..."

    6142 - 1139 = total of 5003 sold in first eight months of 2011. With the planned 60K annual production, Government Motors needs to sell at an 8 times higher rate than the "no dealer demo bargains" rate EVERY MONTH of 2012!

    Summary:
    Tax payer's only real hope of getting rest of their money back hangs on GM's sales in China being able to off set US excess Volt production losses.
     
    Last edited by a moderator: Dec 1, 2011
  17. adoucette Caca Occurs Valued Senior Member

    Messages:
    7,829
    Well the November sales figures are in.



    The Chevy Volt continues to slowly increase its monthly sales and in November, sold 1,139 Volts. (+31 over October)

    On the other hand, the Nissan LEAF sales fell again to just 672 units. (-177 below October)

    So far in 2011, the Leaf has sold 8,738 copies in the U.S while the total sales for the Volt stands at 6,142.

    Which is 14,880 for both or even with $111 Million in Federal Subsidies so far this year (and more in State subsidies), just a paltry 1,352 vehicle sales per month.

    http://green.autoblog.com/2011/12/01/volt-sales-climb-to-1-139-leaf-drops-to-672-in-november/
     
  18. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    23,198
    AFAIK this is the first car designed for CNG:

    "... The Zafira’s natural gas tanks are in the floor of the vehicle,* {and} holds about 55 lbs of natural gas. It should have a range of just over 300 miles. The Zafira Tourer 1.6 CNG Turbo Ecoflex has about 150 HP and puts out a maximum 155 ft./lbs. of torque. It reaches a top speed of 124 mph ..."

    Please Register or Log in to view the hidden image!

    Zafira Tourer Turbo EcoFlex (any fuel mix)
    It lives up to the “flex” part of its name, too – it can run on CNG, biofuel, or a mixture of the two. The Zafira Tourer even includes a 3.7 gallon emergency gas tank (standard gasoline), which gives it a 93 mile safety net.

    Tourer is also more fuel efficient and has lower CO2 emissions ... & the relative low cost of CNG means that the cost of operating the eco-Tourer is half that of a similar gas-driven vehicle. Opel’s green offering goes on sale in January of next year. ..."

    More at: http://gas2.org/2011/12/10/opel-zafira-tourer-ecoflex-runs-on-almost-anything/ or if you read German (or let Google translate) http://www.autobild.de/artikel/opel-zafira-tourer-cng-2327670.html

    And thanks to X-man for calling my attention to the type of car I posted about & predicted - One designed from scratch for CNG, not a standard car with CNG tank stuck in the trunk.

    * As I pointed out in several posts the weight of many parallel small diameter tubes holding CNG is no more than one large one. I.e. the efficiency of CNG tank does NOT depend upon the diameter of the tank. Easy to prove this as I have, when neglecting ends and these "end effects" very slightly favor many small tubes over one big one as they need not stick out the full radius of a closing hemisphere but can be a little flatter. Thus, I strongly suspect Opel's Zafira Tourer has many small ID tube in the floor. A "flat tank" with some what more capacity in same space may be the next generation, especially if surface absorption (like on baked corn cobs) is used.


    Billy T had said: "Circular pressure tanks ALL have efficiency 1/4t, independent of their diameter."
    Authur's never admitted error is to forget that the circumference also goes up linearly with diameter.
     
    Last edited by a moderator: Dec 12, 2011
  19. adoucette Caca Occurs Valued Senior Member

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    7,829
    Their photo of the Combo CNG/Gas fuel system:

    With 4 fuel tanks.

    1 tank for gasoline and 3 very TYPICAL Steel CNG Cylinders. Which are not part of the floor, or in any way shape or form at all like what Billy suspected: Thus, I strongly suspect Opel's Zafira Tourer has many small ID tube in the floor.

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    Arthur
     
  20. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    That is NOT the car I posted about. You are still making irrelevant posts. It is a standard car ADAPTED to CNG by addition of three large CNG tanks - NOT designed from scratch for CNG like one I posted about which DOES HAVE FUEL TANKS IN THE FLOOR.
     
    Last edited by a moderator: Dec 12, 2011
  21. Trippy ALEA IACTA EST Staff Member

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    Not according to the Motor industry, Billy.

    According to the Motor industry Arthur is right.

    Here's the Cutaway for the 2012 Opel Zafira Tourer CNG Turbo ecoFlex:

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    Source
    Note that it has the tanks in the same place that Arthurs schematic shows them.

    I'm also going to take the time to point out that the Opel Zafira was originally designed to run on Liquid Hydrogen, using a fuel cell, so it was designed, from scratch with compressed/liquid gas as fuel in mind - it even had all of the neccessary paraphenalia for storing the liquid hydrogen at 20k.
     
  22. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    23,198
    That is probably correct, I was only quoting their text - which said "tanks in the floor." I don't consider the three standard CNG tanks shown in your cut-away to be "tanks in the floor" but do admit they are more integrated into the body, not just stuck inside the trunk as is often done.

    Also the head lights while similar seem to be different - more sweep back in the photo I posted and the "license plates" are not the same - Yours /Author's is not showing the name "Zafira" in your or Author's photo. Even the "flex fuel names" are not the same (One is "Ecotec" the other is "Ecoflex"). Thus, only thing I am completely sure of is both are made by Opel.

    If it is the same car, then I will need to wait a few more years before a commercially available "designed for CNG" car takes advantage of the fact pressure tank efficiency does not depend upon tank diameter so many small ID tanks in the floor can weight the same and hold the same mass of CH4 as one or two bigger ID tanks as well as add rigidity to the floor, lower the CoG, and have less "liquid sloshing" on curves of mountain roads.

    I.e. unit lengths of volume goes as R^2 and of wall mass goes as CT, where C is the circumference and T is the thickness, both of which also go as R so their ratio does not depend upon R the radius.

    I also note that you and Author seem to have different cars from each other. Yours has two identically tanks plus one bigger one and Authors has all three quite different from each other. Your car has an external form, including window shapes, very much like the one in my photo, but Author's has "flat" rear end, not as aerodynamic as the two we show. All These differences make it hard to believe we are speaking of the same car, but it is not very important to me if none have "tanks in the floor" as text I quoted asserted.
     
    Last edited by a moderator: Dec 12, 2011
  23. adoucette Caca Occurs Valued Senior Member

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    7,829
    Yes Billy, those tanks are in the floor.

    As opposed to being in the trunk.

    Of course they ARE typical CNG cylinders.

    Nothing at all like you have been suggesting.

    Arthur
     

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