Why not ammonia, NH3, as liquid fuel?

Discussion in 'Chemistry' started by Billy T, Feb 26, 2007.

  1. Nasor Valued Senior Member

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    6,221
    Haha, didn't you read his post 146? There's no need to know how to convert units. That's why he says nonsensical things like "USA alone roughly consumes 7 terawatts of electric energy/year."
     
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  3. dixonmassey Valued Senior Member

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    As I said, I have a good company.

     
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  5. Nasor Valued Senior Member

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    The mistake was that you tried to divide 30 TW by 500 (or 1000) MW to try to figure out the area needed. You didn't understand that you were dividing TWhours (a unit of energy) with 500 MW (a unit of power). I tried to point out that if you convert 18 trillion kWh ours/year to power you get only 2 TW. in fact, here is my exact quote:
    But you STILL didn't seem to see the difference, and said "I don't know how you come up with 2 TW." even though I had clearly explained it.
     
    Last edited: Aug 24, 2009
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  7. Nasor Valued Senior Member

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    In the text you quoted I was correctly giving the world's average power consumption. You, on the other hand, said "7 terawatts of electric energy/year" which is gibebrish because 7 terrawatts is a unit of power, not energy. Saying "7 terawatts of electric energy/year" is nonsensical.
     
  8. dixonmassey Valued Senior Member

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    2,151

    What a load of bullshit. You think the world uses 30 TW of electricity??? Try 2 TW. http://www.indexmundi.com/world/elec...nsumption.html That's little bit esoteric way to say that "world's average power consumption"as for my taste. Again world consumes energy not power. Besides your link gives world's electricity consumption as 16.88TW*hr/year. It would be OK if you said

    16.88*10^12/(365*24)=1.93GW (G not T) is an average hourly world's energy consumption. How do you consume power? What is world's average power consumption exactly?
     
  9. Nasor Valued Senior Member

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    6,221
    Christ, you really still don't get this do you... you know what, I'm not really in the mood to hold your hand and walk you though the ways in which you've been a dumbass. I'll leave it to everyone else here to decide which of us is the stupid one. Since I underatnd the difference between units of power and energy, I'm guessing it won't be me, but I suppose we'll have to wait and see...
     
  10. dixonmassey Valued Senior Member

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    2,151
    I think I'm missing something, cant figure it out. If world's energy generation is roughly 18TW*hr/year.

    A 1000 MW power station produces on the average 1000*10^6*24*365*0.8=7 TW*hrs of electricity. It takes only three 1000MWatters to cover World' energy needs. This is obvious nonsense, there are dozens if not hundreds of 1000 MW power stations.

    Here is the list of the largest ones in the USA.

    http://www.eia.doe.gov/neic/rankings/plantsbycapacity.htm

    The Grand Coulee alone has capacity of 7,000 MW. Any suggestions?
     
  11. dixonmassey Valued Senior Member

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    2,151
    As long as you are sure you understand, I'm not so sure about that, your last answers don't instill confidence. However, strong ego should make up for the lack of just about anything. Seriously, man, if you think you are an English queen or the sharpest knife in a drawer, it doesn't bother me, enjoy. Equally, I don't really care what you think of my intelligence. Have you read Feynman' "Why would you care what other people think?". This is not to imply that my intelligence is on par with Feynmans, however I like the philosophy of it and I would not really have given a rat' ass what Feynman had thought of me. And you, as far I can guess, are not Feynman reincarnate

    Please Register or Log in to view the hidden image!

    ?
     
  12. Nasor Valued Senior Member

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    6,221
    It would be 18 thousand billion kilowatt hours/year.
     
  13. dixonmassey Valued Senior Member

    Messages:
    2,151
    Yup, mixed . with ,;

    OK, to end this fruitful discussion I'll make a corrected ( extremely optimistic) estimate of the total solar panel area needed to make up for the entire world's electrical energy generation.

    1000 MW power station generates 1000*10^6*365*24*0.8=7 TW*hrs. If global energy stands at 18,000 TW*hr/year, it would take 18,000/7=2571 power stations rated at 1000 MW. According to Ted Trainer

    at Sydney’s 34 degrees, solar incidence of 4.6 kWh/m2/day, a 1000 MW coal-fired
    plant operating at 0.8 capacity produces 19.2*10^9 W*hrs/day, to generate this amount of electricity at 13 % (practical) efficiency, (19.2/0.13)*10^9=147.7*(10^6) KW*hrs of solar energy would have to be collected per day. If solar incidence is 4.6 kWh/m2/day this would require 32.1 million square meters of panels, or 32.1 km2.

    It would take 2571 (1000 MW) power stations X 32.1 km2= 82,530 km2. Since world at large is not Australia, let's make it 160,000 km2 (and up, up).

    Let's buy into a promise of $1/watt of solar panel and mix with circuitry and installation to get $2/watt (wholesale). 1 m2 = 160 Watt = $320. Or, $320*160*10^9=$51.2 Trillions.

    Since it's an enormous investment, the question "How much waste is generated in the production/disposal of solar panels that last 30 years versus 30 years worth of grid energy? " What is the energy required to manufacture/install/maintain 1m2 of solar panels, what is a realistic amount of energy 1m2 of solar panels could produce over its life time. Solar panel is a toxic thing btw. I was looking hard and I could not find much of the useful info on those subjects. Real studies are needed not some industry sponsored BS. One thing I found is this:

    While many of the manufacturing techniques used by heavy industries have been widely criticised by environmentalists for their inefficiency, the MIT study found that new manufacturing systems are anywhere from 1,000 to one million times bigger consumers of energy, per pound of output, than more traditional industries.

    In other words - don't hold your breath.
     
  14. TBodillia Registered Senior Member

    Messages:
    159
    I crunched some numbers a few months back on the question if covering 10,000 square miles of desert with solar panels would be enough to meet the USA's electrical needs. I think I used this company
    www
    .sunwize.com/products/sitebuilt-solar-systems.php
    as the model.

    Surprisingly, the answer was Yes. But, it was still impossible to carry out because of the cost. Using their most efficient systems, it would cost over $17 trillion (not counting any discounts for such a large order!) to cover an area 100 miles x 100 miles. You still had to add in labor, construction supplies, land... The GDP of the USA is only $14 trillion.
     
  15. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

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    23,198
    Assuming you are correct and noting that Brazil is > 3,300,000 square miles and noting that sugar cane and PV cells convert sunlight at about the same efficiency, means less than 1/3 of 1% of Brazil could supply ALREADY STORED ENERGY* for the US needs even if the cane is just burned for heat in a steam electric plant (More than 33% efficient easily) Thus, 1% of Brazil could meet US electric needs.

    Now Brazil is large but the tropics suitable for growing sugar cane is much larger. I.e. Sugar cane on ~1% of the sun rich tropics could supply the world's energy needs and is easily converted into liquid fuel (Alcohol). This energy system is "carbon neutral" and does not supply a steady stream of funds for the terroists like Mid Eastern oil does.

    It does not cost 17 trillion dollars to buy sugar cane - it grows wild even. Both energy systems need about the same amount of land but in the tropic that cost less than 10% of what it would in the USA. Labor there is much cheaper also and many low skill jobs would be created. Thus US could save all of the cost of foreign aid as well as reduce anti-terroists cost and of course eliminate the cost to taxpayers of corn and alcohol from it subsidies.

    -----------
    *Storage cost for PV cells is greater than the cost of the PV cells, but sun-dried cane could be very cheaply stored in large "quansit hut" type structures and of course alcohol could use the same storage tanks tha gasoline now uses, etc. Those quansit huts could be in the US near ports (bulk carriers used for ocean transport) for "energy security" and many more nations would be competing to keep price down compared to the few who export oil; however I suspect it is cheaper to convert the cane into alcohol for transport and storage as the energy density is higher. If celullosic alcohol is not economic (only the cane's sugar is used for alcohol production) then the crushed cane can be burned near the fields for electric power and used in energy intensive industries, like aluminium production. I.e. the energy in the crushed cane is exported in the form of aluminium etc. (Brazil, one of the world's leading producer of aluminium, currently gets ~10% of its electrical energy as well as all the heat needed for the distillation of the alcohol from burning crushed cane.)
     
    Last edited by a moderator: Aug 24, 2009
  16. dixonmassey Valued Senior Member

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    2,151
    Billy_T, I didn't know you don't like Brazil so much as to destroy it piece by piece by sugar cane so Americans could chill their fat asses etc. How you are going to grow cane , industrially or chain gangs working the fields? Are you going to use chemical fertilizers or slash and burn? What about soils, for how long poor jungle soils would last before a field is transformed into deserts? What about jungle, global oxygen it produce, what about a few remaining Indians? What the point/rush? Just to prove viability of bio? No it's not viable in the long run. We'll be lucky to get fed. I doubt chain gangs would earn much more than a bowl of soup or two.
     
  17. Nasor Valued Senior Member

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    6,221
    You should just give up on math forever. If you have 2571 power stations that are each 1 GW, and the solar cost is $2/watt, the total price would be $5.14 trillion, not $51.2 trillion.

    Edit: For the US alone, you would need about 1 TW of capacity, which would be about $2 trillion. Which is a lot of money, but not that much compared to some of the things we've been spending money on recently...
     
    Last edited: Aug 24, 2009
  18. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    Messages:
    23,198
    About 10% of Brazil's agriculture land is now abandoned pasture - over grown with weeds. (I bought ~100 acres of one farm for $23,000 USD about 15 years ago.* I invested a few thousand dollars more in plowing and seeding it. It had a dozen scrawny cows on it trying to find good grass to eat (lots of walking up and down the hills) when I bought it. Ten years later when I sold it I had 50 fat steers on it. I did buy a little lime, but no fertilizer. A well managed cattle farm will let the cows provide the fertilizer.)

    As far as labor is concerned: In about 5 years (not sure by memory) the exsiting law requires only land too steep for machine harvesting will have cane cutters working it. I think more than half is now harvested by machines. (Some of my farm's hillsides were too steep for tractor plowing but man with four oxen had no trouble - They only plow when going downhill then climb back up for next run down hill. It was amazing to watch him, a small man with a little stick, ordering those huge beasts around.) I am sure you could grow cane on my farm for several years, and doing so would probably be more profitable if there were a sugar/ alcohol plant near by not more than ~30 miles away, but putting it into another crop or back as pasture would be required periodically to avoid excessive monoculture use of the land.

    "No it's not viable in the long run." You got to be kidding! It is based on the sun, not finite petroleum. You will painfully learn in less than a decade that only this system is viable.

    ----------------
    *It had lake of a couple of acres, and two 2-BR simple houses. - I used one on weekends and my hired man (who killed the weeds with his hoe) lived in the smaller one with wife and child. His pay back then was ~100 USD / month and he worked 44hours / week. Minimum wage now under Lula is about $300 USD (or more when the dollar is weak as it is now). Some of my absentee neighbors were mad at me as I over paid my help.
     
    Last edited by a moderator: Aug 24, 2009
  19. Trippy ALEA IACTA EST Staff Member

    Messages:
    10,890
    No.

    1W=1J/s

    Hours doesn't enter into it - period, you've divided them out,so there's no need to consider them.

    If the power stations of the USA generate 2 GW of electrical energy, then they're generating 2 GJ of electrical energy every second.

    Personally, i've never liked kWh as a unit, I find them annoying for a number of reasons. The only advantage I can really seeto them is that the numbers themselves may be less cumbersome for engineers and consumers to work with.

    I'm sure most people would prefer to get a bill for consuming 875 kWh of electrical energy than 3,150,000 kJ of energy.

    If you're wondering how I worked that out.
    W=J/s
    Therefore:
    \(kWh=\frac{Jh}{s}\)
    1h=3600s so
    1kWh=3600J
     
  20. Trippy ALEA IACTA EST Staff Member

    Messages:
    10,890
    Yes.
    You appear to have multiplied by 0.8,which is un-neccessary.
    You appear to be comparing TWh with TW.

    If you want to do this calculation, the easiest way to do so would be to use the 2TW figure which has already been calculated.

    1TW=1,000,000 MW

    (Tera- =10^12 according to the SI system of units).

    So, 2TW would require 2,000 1,000 MW power stations.
     
  21. Trippy ALEA IACTA EST Staff Member

    Messages:
    10,890
    I like your attitude - too many farmers i've encountered (especially bad among dairy farmers) view effluent as a liability to be disposed of, not an asset to be used.
     
  22. dixonmassey Valued Senior Member

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    2,151
    Plowing and seeding is little bit different than plowing, seeding, cutting, plowing seeding, cutting, fertilizing season after season. From what I've read Amazonian soils are poor and not suitable for intensive agriculture. They are not even well suited for pastures. In the tropical forests, because of the fast nutrient cycling, almost all the nutrients are locked up in trees' biomass. Once trees are removed poor, vulnerable soils remains behind.


    Not quite, since cows are sold out and with them all the minerals they've collected up to build their bones and tissues.

    I've mentioned labor because "manual" agriculture, as a rule, produce energy surpluses while industrial, mechanized agriculture is an energy hog.

    Don't forget fertilizers, lime, etc. Yup, Brazilians greatly boosted production of the commodities like soy grown on poor soils. I took enormous amounts of lime and fertilizer.

    You've forgotten soil. You must don't realize all the vulnerability of the soils. Wasting soils to grow fuel is shortsighted. Since energy output/energy input ratio for biofuels is hovering around 1 (in the best case) it does not make much sense energy wise. OK, this ratio for Brazilian bio fuels most likely is greater than 1 (by little bit), but energy gains nevertheless are marginal.
     
    Last edited: Aug 25, 2009
  23. dixonmassey Valued Senior Member

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    2,151
    No, 0.8 is standard multiplier since no power station works 365 days/year. I don't compare TW with TW*h, at some point I made mistake like that but I've corrected it later.

    2TW (power units) is obtained by dividing world's energy production/yer = 18000TW*hrs/(365*24) = 2.054TW = world' average power generating capability.

    Again, since no power station works 365 days; 2000/0.8= 2500 1GW power stations are needed.
     

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