Why not ammonia, NH3, as liquid fuel?

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

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

    You know next to nothing about Brazil or sugar cane economy. It must be grown relatively near the markets and even closer to the fermentation/ distillation plants to be economically attractive. (Cane is too bulky to haul more than about 3o miles.)

    Thus most of Brazils more than 100 fermentation / distillation plants are more than 500 miles from the Amazon. More than half are in the state of Sao Paulo as that is the main market. Soil in Sao Paulo and Mato Grosso (nearer to Rio) states is fertile and where most of the agriculture activity of Brazil is concentrated or in more southern states, 1000 miles from the Amazon. (Amazon soil does tend to be poor.)

    After the best trees of the Amazon are illegally cut to convert into fancy Mahoney etc. furniture for export mainly the wealthy of wealthy nations, the woods is set fire to hid the crime. (One good tree is equal to a year’s pays at the minimum wage - and Amazon is very large, so hard to stop this activity - only feasible way would be for rich people to stop buying mahogany furniture.) After a few years some absentee land owner may clear the burnt stumps, fertilize it, seed it with grass and raise cattle on it - they can economically be transported 500 miles if need be, but new slaughter houses are being built closer to the Amazon now.
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  3. dixonmassey Valued Senior Member

    No, you cannot calculate it like that. You got to calculate the area required for a solar equivalent of 1000 MW conventional power station. Even though power output remains the same 1000MW it's quite obvious that 10km2 solar station is less expensive than 32km2 power station.

    Ok, let's use numbers of Ted Trainer data I've cited, if my numbers are too pessimistic (he published a book, I guess he triplechecked his math). Trainer estimate costs of a solar equivalent of a 1000 MW conventional power stations at 48*10^9. It takes 2571 power stations like that tho generate all world's electricity.

    $48*(10^9)*2571 = $123 trillions. Of course, you can play with better efficiencies (he used 0.13) and less expensive panels (he used $1500 per meter square), all costs included. However, it takes mighty tweaking to go from $123 trillions to $5 trillions.
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  5. Trippy ALEA IACTA EST Staff Member

    The mistake you made was a little bit like talking about tomatoes in a conversation where everyone else is talking about apples, and then later claiming it's a typo.

    I'm well aware of how the 2 TW is calculated.
    I explained it already, and elaborated with a dimensional analysis, you even replied to one of the posts I made on the subject. Besides which, you're not paying attention here, I was discussing Joules in my post, you're converting to watts.

    Learn the difference.

    You don't need to explain to me how to calculate it.

    Also, quoting 4 significant figures when your least accurate data is only two significant figures is simply wrong.

    Ooh, you got me.
    Then again are we talking about Base load capacity or the name plate capacity? (And yes, yes, don't bother, I know).

    I also feel compelled to point out that the capacity factor (what you're referring to) varies widely depending on the kind of power plant being considered, and the location of the power plant.

    According to the US DOE, Capacity Factor varies between 22-97%.
    Even among Hydro stations (for example) vary between 25% in France, and 59% in Canada.

    According to the world association of nuclear operators, between 2004 and 2005, Nuclear power stations only had a capacity factor of about 86%

    Besides which, the 18000 TWh you keep bandying about (at least according to the IEA report at least) is the fossil fuels alone.

    So, unless you've got some sources to back these claims up...

    But if you wanna keep picking at nits...
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  7. Nasor Valued Senior Member

    Dude, look again at your own post. You're the one who decided to base your calculation on $2/watt. If you know it costs $2 per watt generated and you spend $51 trillion, you just bought 25 TW of generating capacity, which is an order of magnitude more than the world uses. You obviously screwed up the math somewhere, although I don't really feel like scrutinizing your post to figure out where.

    The Moura power station in Portugal is 62 MW at a cost of E250 million, which is about $5 per watt. The Waldpolenz solar power station in Germany produces 40 MW and cost E130 million, about $4.50 per watt. California is building a $550 MW solar farm for about $1 billion using the latest (cheapest) thin-film solar cell technology, so $2/watt is about right with the latest technology (in California, anyway).

    The $48 per watt figure from Ted Trainer is absurd, as demonstrated by the cost of real-world solar plants that are actually being built. Interestingly, the $4.5 per watt solar station in Germany was being built in 2007 when Trainer's book was published, which seems to indicate that he didn't make any effort to check his estimated costs against demonstrated real-world costs. This makes it appear that he either had an agenda, or was simply incompetent.
    Last edited: Aug 25, 2009
  8. dixonmassey Valued Senior Member

    No, I repeat, you straight forwardly multiply generation power times $2 to get costs. You cannot do that as I wrote above, you need to calculate the area of a solar installation, area number takes into account efficiency. The roughest you could do is to divide your number by efficiency of you liking.

    OK, I repeat, cost should be calculated like this

    (cost per watt)*(solar energy density per m2)*(Total Area of station)= Total costs. That's the way most people estimates it.

  9. Nasor Valued Senior Member

    I am not exactly sure what you mean by "solar energy density per m^2." If you mean the density of the solar flux striking the surface, then your calculation makes no sense. If you're talking about the solar electricity per m^2 that can be generated, then you are simply multiplying the cost per watt by the plant's total power output, which is what I said.

    The costs scale roughly with the power output. If anything, it would probably be cheaper per watt to make a larger station, with economies of scale and all.

    Do you even remember your own posts? From your post #182:
    If the solar plant costs $48 billion and has a capacity of 1 GW, then it's $48/watt, about ten times higher than the cost/watt of the solar plants that were being built when the book was written.

    But even if we go with these new numbers you just posted, it's still bullshit. If Sydney gets 340 watts/m^2 of solar flux, you will be able to generate at most about 70 or so watts/m^2. If the panel costs $1500/m^2, you would be looking at $20 per watt, roughly four times what has been demonstrated.
  10. dixonmassey Valued Senior Member

    Ok, Nasor, let's use Portugal's station you've mentioned as an example. First, the numbers you cite are given by newswires. Second, the cost of Euro250 millions was first mentioned in 2006. It would be quite unusual for the actual costs of construction to match the estimates. I could not find exact construction costs.

    Here is more or less technical report on this station.



    The facility consists of 2520 large assemblies (Figure 1) of solar panels (trackers), mounted on towers. The panel assemblies are mounted on a flat frame at a fixed Zenith
    angle of 45 degrees and track the sun in Azimuth over a range of 240 degrees. Each
    panel assembly is 142 m2 (13 x 10.9 m) and contains 104 polycrystalline silicon modules,
    each capable of about 180 W peak. The site occupies 250 hectares of land. The power delivered to the grid by the total of 262080 panels is ~46 MW peak and ~10 MW
    average (93 million KW-h per year).
    The plant has been in full operation since Dec.

    I think the bolded text explains why we cannot understand each other. I think it's because $/watt installed is NOT very useful unit for calculations of costs, it's rather very misleading. Which watt does $2/Watt installed refer to, peak, average daily, some other watt?

    Let's calculate what is the approximate price per 1m2 of panels;


    thus, cost of 1m2 is around $838. OK, let's make it $500/m2 which is within a reach of Ted Trainer's $1500/m2.

    Therefore, Ted Trainer's approach to calculate cost is much more sound than that using $/watt. You can play with efficiency numbers, you can play with $ per m2 of panels, but his approach is fairly sound otherwise.

    BTW, I've used $320/m2 of panels in my calculation, of course, the reasoning behind $320/m2 was faulty, but it's quite optimistic number

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    Last edited: Aug 26, 2009
  11. dixonmassey Valued Senior Member

    As I said $/Watt is a tricky number. Energy is sold in Kw*hrs. 1GW station produces 0.8*24*365*10^6 Kw*h. Assuming zero operating costs and 20 years life span, it's

    (48*10^9)/(0.8*24*365*20*10^6)= $.34/Kw*h; Going price for Kw*h in states is around $0.1/Kw*hr. Even if you add $.06 for operating expenses, $0.4/kw*hr is much less scarier amount than $48/watt.

    You should explain me what manufacturers of solar panels mean if they say "$1/watt". Just think about it in this way, you purchase "$1/watt" solar panels and installed it in Arizona. In a few years you had moved to Minnesota together with your "$1/watt" panels. What would happen? let me guess, you would apply your straightforward way to calculate the costs just to get surprised.

    BTW, British government stopped subsidizing home solar panels, because British experts came to conclusion that home solar panels will never pay back their costs and it's more wise to spend "solar panel" money to insulate homes.
    Last edited: Aug 26, 2009
  12. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    You exhibt very little understanding of the cost of electricity. I.e. You have totally neglected the main cost, which is the interest paid on the capital during those 20 years.

    Also a significant part of your electric bill is the interest on the distribution system, transformers etc. capital investment. Then there is the relatively minor fuel and labor costs.

    Furthermore it is silly to assume that the plant operates at 100% of capacity, 24/365 for 20 years. Even base load plants, like nuclear plants, rarely have more than 85% utilization of their capacity and of course the price of electricity must cover the capital cost of the peaking units, like gas turbines, which may operate only 5% of the time.
    Last edited by a moderator: Aug 26, 2009
  13. dixonmassey Valued Senior Member

    It's just very rough approximation, I've included 0.8 utilization factor, let's assume bankers are environmentally conscious and $0.03 out of 0.06 cents, I've added to calculated $.34, would satisfy them, fat chance but let's assume. Besides, it appears that tax and other government handout finance solar industry to a large extent these days.
  14. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    Yes it is - like a home buyer figuring he can afford the house by neglecting the interest payment the bank will collect on the mortgage.
  15. dixonmassey Valued Senior Member

    First, my goal was not to give good estimates for the price of 1kw*hr but to show that there are issues with using $/watt for the straightforward estimation of solar power station costs.

    Second, that's raises a question does Euro 250 millions supposedly spent to build Portugal station counts in interest to be paid for 20+ years.
  16. Billy T Use Sugar Cane Alcohol car Fuel Valued Senior Member

    If that is your objective, then just point out that even if the solar cells were free, the price of the power would not be reduced by even 1/3.
    We have free fuel power stations already: hydro-electric power. PV cell power stations require a lot of copper wires to collect the energy difusely spread over a large area. / Structures to hold the cells. / DC to AC converters. / huge storage system costs (if to be more than 15% of the total supply as then "grid storage" IS NOT FOR FREE.)
    Last edited by a moderator: Aug 26, 2009
  17. Trippy ALEA IACTA EST Staff Member

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

    Yes, and here is NYT article on it:
    http://www.nytimes.com/2009/09/09/b...html?_r=1&scp=2&sq=chinese solar plant&st=cse

    Which includes: "… First Solar, based in Tempe, Ariz., is also likely to build a factory in China to make thin-film solar panels, said Mike Ahearn, the company’s chief executive. “It is significant that a non-Chinese company can land something like this in China,” Mr. Ahearn said in an interview. ..."

    My local Sao Paulo paper gives even more details some of which follow:

    Note China is already the world's largest maker of solar cells. - For example, China's SunTech company alone makes* more that the US does, but they are the more efficient silicon based cells, not the cheaper, less efficient cadmium based cells this Manhattan island sized plant will use. - In the US, where labor costs are higher, almost 2/3 of the cost of solar cells power is installation etc. costs. (Called BoS, Balance of System.) Thus, efficiency is more important than in China. (Also note that even if the cells were free, the cost reduction of the power would only be 1/3 in the US.) US based First Solar got the job as they have the cadmium cell technology, but China will soon have that too when the factory is built there. This huge solar cell plant will be installed in Mongolian desert -the first of 6 for 12 GW total using the same transmission lines. In the worthless desert land, efficiency is less important than cost per square mile of collector, if labor is cheap.

    China has serious pollution problems and is working hard to solve them. (World leader in putting electric cars on the street with about 250,000 added to the fleet in 2009 alone.) Also for example, installing more wind machines (by power capacity) each year, now that the rest of the world combined. This same Mongolian area will have 6.95 GW of wind power using the same distribution system on cloudy but windy days. Likewise near the world's largest hydro electric dam, is being built "three gorges on land" wind power plant of equal capacity. - A clever idea as when there is good wind, no water will be released. I.e. the dam is the storage system for the wind system. - Together they are cheap base load power. There are many other wind power plants of very large size underconstruction. Some are finished and only waiting for the transmission lines to be completed. China is building several "smart grids"

    China is also bringing on line a new nuclear power plant every three or four weeks. And building 6 super-critical steam coal fired plant which are about 50% more efficient than normal coal plants. China already has 310 mega watts of simple combustion biomass power and is actively exploring cellulosic alcohol as the US is too. By 2020 China, under the original plan of two years ago, which has just been revised upward, China will get 20% of its electric power from renewable sources - the US will get less than 2%, even by 2020. Despite all this effort, because China is growing so rapidly, it will need to continue adding a new coal plant to the grid about every 8 or 9 days for many years.

    *Most were exported before the current economic crisis – To keep these factories busy, is the main reason China decided to get 20% of its power from solar energy (wind is included). In the Chinese hybrid economic system (State directed expansion of infrastructure and market directed for consumer goods) they do not need to wait for market forces to invest in renewable power. - In more capitalist systems, the lower cost of fossil power (to the electric company producer) makes renewable power less attractive as the producers of power from coal and oil are allowed to ignore much of the total costs - pollution costs, including oil spills, land and river damage with the mines, CO2 & SO2 (acid rain)**, etc. But in China renewable power is more competitive as these "not out of my pocket" costs to society are now charged to oil and coal also in the decision making process. In many ways, IMHO, the Chinese have evolved a better economic system - part of the reason why they have averaged double digit growth for three decades.

    **For example, American Electric Power, based mainly in Ohio and the near by states, killed the more desirable fish in Adarondack lakes, lessened their value as tourist resorts, and damaged many more Eastern forests, but never paid a cent of this cost.
    Last edited by a moderator: Sep 9, 2009
  19. rwendell Registered Member

    Energy and Power

    Why are some participants in this discussion confusing units of energy and units of power? There is even talk of CONVERTING (?!?!) one to the other. YOU CANNOT EVER CONVERT UNITS OF ENERGY TO POWER OR VICE VERSA.

    They are two very different concepts. Power is the rate at which energy is used. If you integrate that over time, you have the total amount of energy used during that period of time. One is not the other and never can be, so why this talk of converting one to the other? The very idea of such a conversion is absurd and implies a total lack of even the most basic understanding of what either is.

    Power is precisely analogous to the flow rate of the water through a pipe and energy used is exactly analogous the amount in the tub after the period under consideration. Can you convert the rate of water flow through a pipe to a specific quantity of water? Of course not! First, in most practical situations the rate is variable, so a simple calculation of the total amount of water exiting a pipe in a given period is not feasible. The most practical method is simply to measure the resulting amount of water in a receptacle at the end of the given period.

    So the whole idea of converting kilowatt hours into watts is absurd. It's precisely the same as pretending you can calculate the rate at which water exited the bathtub faucet by simply measuring how much water is in the tub.
  20. Nasor Valued Senior Member

    Specifically what posts are you talking about?

    The energy figures were all for a given unit of time (usually a year, depending on what part of the discussion you're talking about), making it easy to calculate average power consumption (or generation) during the year...
  21. Trippy ALEA IACTA EST Staff Member

    And your analogy is flawed.

    Perhaps you should pay attention to the discussion.
  22. Larry Johnson Banned Banned

    After reading this thread, I'm looking for reassurance as to whether it stands to reason that if Hydrogen becomes the fuel of the future, that it will most likely be delivered in the form of Ammonia? Right? Since, the only reason we're interested in Ammonia is because of the Hydrogen content, isn't it basically just an (better) alternative to using pure liquid Hydrogen? It (Ammonia) can be used in the same fuel cells or internal combustion engines that Hydrogen can, correct?
  23. Walter L. Wagner Cosmic Truth Seeker Valued Senior Member

    Old thread, but yes, NH3 is a good storage medium of H, and very reactive. However, it is safe enough (and the molecules large enough not to migrate causing brittling of metals) to store in metal tanks. It is stored in metal tanks 'everywhere' on farmland for fertilizer applications.

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