Visual – How much material does it take to run a 3,600 MWe coal plant

Utility companies that operate both coal and nuclear power plants rarely use the important communications techniques of comparison and contrast to help people understand the benefits of nuclear energy. There is some business logic behind that policy. I have a different set of interests and am not constrained by a need to protect any particular capital investments or decision making process.

This clip, generously made available to the world at the Energy Site Visits page on Switch – To a Smarter Energy Future provides the first part of the comparison – a visual representation of the daily fuel deliveries to a single large coal installation.

The same page provides an inside look at a slightly smaller output nuclear plant.

Ideally, I would like the second clip to be from a site like Palo Verde, which includes three nuclear units that have a combined output that is slightly greater than the Parrish coal unit featured above. For now, I will make do with a picture that does a reasonable job of illustrating the contrast.

Palo Verde Nuclear Power Station

Palo Verde Nuclear Power Station

About Rod Adams

39 Responses to “Visual – How much material does it take to run a 3,600 MWe coal plant”

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  1. Engineer-Poet says:

    That’s one impressive heap of coal.

    What would be more impressive is a comparison to the number and size of reactor fuel elements needed to provide the same amount of energy.

    • James Greenidge says:

      Re: “That’s one impressive heap of coal. What would be more impressive is a comparison to the number and size of reactor fuel elements needed to provide the same amount of energy.”

      A MAJOR failing and whole point oversight of an otherwise informative video. Nuclear education just can’t seem to target the barn much less a side. Really didn’t really need the unexplained post-Fukushima project abandonment mention tho.

      James Greenidge
      Queens NY

  2. Engineer-Poet says:

    The mountain of coal is most impressive.

    It would be even more impressive to compare that mountain to the small set of enriched fuel elements needed to provide the same amount of electricity.

    • Engineer-Poet says:

      So of course after I refresh and check my mail looking for a confirmation link, I re-write my comment… and that’s when the first one appears.

  3. Jason C says:

    The contrast in the cleanliness of the two sites is remarkable. Even the control room of the coal plant was dirty. It looks as though soot gets into every crevice and surface available. I was expecting the narrator at the end of the coal segment to say “if you live in Houston, chances are you are *breathing* this pollution right now.”

    They didn’t mention how long a 100 ton coal car last in the boiler, but I’ve read it’s about 20 minutes. Visually the contrast in material doesn’t give the full impression of the volumetric differences. By mass, it’s about a 2 million to one difference, but I’d wager to say that number goes up significantly in the volume category.

    • Cyril R. says:

      3600 MWe of coal at 0.8 capacity factor would gobble in the ballpark of 10 million tonnes of coal per year.

      That’s over 300 kg of coal per second, on average. About 400 kg of coal per second that it’s running at full throttle. Imagine flinging a medium sized car into the air every 4 seconds.

      20 minutes? The 100 ton coal car doesn’t stand a chance. It’ll be gobbled up in 4 minutes of full power operation at 3600 MWe.

      Fissioning an atom of heavy metal (U, Pu, etc.) produces some 200 million electron-volts. This compares to combusting an atom of carbon, at 4 electron volts.

      That’s a factor of 50 million in volumetric energy density.

      I looked at lifetime energy requirements for different energy sources, assuming everything comes from one source.

      2500 MWh of useful work required.

      Efficiency multiple for LWR is 3, for coal 2.5, for LFTR 2. So need 7500 MWh thermal U3O8, 6250 MWh thermal coal, 5000 MWh thermal ThO2.

      Biomass density = 0.5 (fast growing wood for energy)
      Coal density = 1.5 (anthracite, best quality coal)
      U3O8 density = 8 (average)
      ThO2 density = 10

      Biomass needed: 4,800,000 liters
      Coal needed: 480,000 liters
      U3O8 needed: 6 liters (soccer ball)
      ThO2 needed: 0.02 liter (golf ball)

      So with today’s LWR you have a factor of 80,000 improvement in volume over coal.

      With advanced breeders such as IFR/LFTR you get a factor of 24,000,000.

      • AtomikRabbit says:

        We need to pound this in – the unassailable trump card of nuclear: “It’s the Energy Density, baby!”

        Or, “Why C+O2, when E=MC2?”

      • Engineer-Poet says:

        1734 million megawatt hours divided by 929 million short tons is 1.87 MWh/ton.  3600 MW is 1930 tons/hr or about 19 rail car’s worth.  Annual consumption at 0.8 capacity factor would be 13.5 million tons.

        If that was a million-ton heap, it would last less than a month at average power.

        Fission products from an Integral Fast Reactor plant producing 3600 MW(e) would likely be under 5 tons/yr.

        • Cyril R. says:

          My tons are metric, rather than nonsensical and shortsighted. Imperial units make my head swim.

          FPs from IFR would be around 900 kg/GWe-year, so 2.6 real tons/3600 MWe /@ 0.8 CF.

          • Brian Mays says:

            The usual spelling for the SI unit is tonne.

          • Stephen says:

            I never get this nuclear energy to E=mc2 link. The same amount of m is turned into E in a chemical reaction as in a nuclear one. That’s what E=mc2 means.

          • Rod Adams says:

            @Stephen

            In a chemical reaction, the value of “m” is exceedingly tiny compared to the value of “m” in a typical nuclear reaction.

            You are correct that the equation still holds, but the result is different by about 7 orders of magnitude (powers of ten).

          • Stephen says:

            @rod

            in a reaction yes, but in a chemical power station(coal) and a nuclear power station the value of m is the same – because E is the same.

            Perhaps not the place to get into it… but in one atomic show G. Cravens said how she couldn’t believe how nuclear power just provided heat to boil water, instead of some complicated process of sucking electrons.

            In a similar way I sometimes think people are put off by E=mc2. Personnally I just think of nuclear energy as just stored electrostatic energy, there’s no mystery in why two positively charged fission fragments would repel each other and generate heat.

            Sometimes feel E=mc2 is a red herring, it’s the effect of energy release not the cause of it. Pedantic I know, but the slight shift in emphasis might be beneficial.

          • Albert Rogers says:

            The fact is, that for a gigawatt-year of energy, the mass that disappears is the same one GW-yr/(c squared), which you can do in SI units, regardless of whether the energy reaction is chemical or nuclear. I think it’s quite a small fraction of a gram. But it is possible to measure the mass of the fission products of a fissile nucleus, using individual typical atoms, and actually have measurement of what a tonne of U-235 will lose. The inordinate mass of carbon and oxygen for a GW-yr of C+O2->CO2 is so impossible to measure to that accuracy, that the “Law of Conservation of Mass” was for almost all intents and purposes absolute, even in the days of Kelvin, Maxwell, and Faraday.

      • Jason C says:

        Excellent analysis! This will be the makings of some great memes. One could imagine even greater comparisons if the volume of gaseous waste streams are compared to solid pellet waste streams. Through my own research I’ve discovered the packaging or containers, including pools or dry casks, make up the majority of the volume for the nuclear ‘waste’ stream.

        • Swany says:

          It is fundamentally the fact that nuclear reactions are occurring that allows mass to be converted to energy. In conventional chemical reactions, e.g. the burning of fossil fuels, mass is conserved – the energy evolved is due to the fundamental laws of thermodynamics wherein molecules react to form products and, in the case of exothermic combustion reactions, release energy on their way to a more stable chemical state. The massive difference in energy density between nuclear fuel and fossil fuel is due to the conversion of mass to energy rather than simply converting the same mass from one thermodynamic state to another.

          If we could better communicate such concepts to the general public perhaps it would go some distance toward providing confidence that nuclear science is well understood. This would counter the perception that nuclear is dangerous, unknown, and can’t be controlled.

          • Kasper says:

            Except it is not.

            ANY release of energy is accompanied by a loss of mass. Nuclear reactions are just so much more powerful that it is easier to measure the mass difference.

            Nuclear reactions are powerful because the nucleus is so tiny and the charge so high, not because it converts mass. The laws of thermodynamics still work for nuclear reactions.

            You are right of course that nuclear reactions are well understood and that the public should be better educated.

  4. Rich Harrison says:

    I’ve been struggling with getting my mind wrapped around the relative sizes of the waste streams of coal vs nuclear: one is stunningly huge (when both the coal ash AND CO2 is included) versus a manageable amount of spent fuel assemblies. How anyone can seriously believe that carbon capture and sequestration on a global scale is even remotely feasible is beyond what I can comprehend.

    Rich Harrison
    Charlotte, NC

    • Paul Lindsey says:

      The anti-nuclear meme is to quantify the nuclear once-used fuel in terms of tons because it sounds huge.

      • Albert Rogers says:

        Worse still, I’ve seen Japanese blog translations in which the spilled neptunium and plutonium (Aargghh!) is measured in becquerels, or rather TeraBq. A bequerel is so tiny that the healthy medium sized human body’s complement of potassium bombards it internally at a ratte of about 400 or 500 Bq. Avogadro’s number, anyone?

  5. AtomikRabbit says:

    “How anyone can seriously believe that carbon capture and sequestration on a global scale is even remotely feasible is beyond what I can comprehend.”

    I’m sure the fossil fuel industry, which as the TV commercials constantly remind us, has been solicitous in protecting our health for the past 150 years, will find a way to safely and permanently sequester the trillions of tons of CO2 required in a couple of small co-located geologic repositories.

    What could possibly go wrong?
    http://en.wikipedia.org/wiki/Lake_nyos#The_1986_disaster

  6. Pete51 says:

    Ben Heard at Decarbonise SA has a good visual comparison of the energy density of uranium versus coal:

    http://decarbonisesa.com/energy-density-explained-using-a-satchel/

  7. William Vaughn says:

    Stephen queried:
    “I never get this nuclear energy to E=mc^2 link. The same amount of m is turned into E in a chemical reaction as in a nuclear one. That’s what E=mc^2 means.”
    and Rod answered:
    “In a chemical reaction, the value of “m” is exceedingly tiny compared to the value of “m” in a typical nuclear reaction. You are correct that the equation still holds, but the result is different by about 7 orders of magnitude (powers of ten).”

    Not to make too fine a point of it, but the actual source of the high ratio of nuclear energies to chemical energies comes not from the high mass ratio of the nucleon to the electron(~2000) but from the fact that nucleons are confined to a space with a linear dimension 10^-5 times the space of that of the electrons. And the energy is proportional to the square of the inverse of this ratio times the inverse of the mass ratio i.e. En/Ee = (10^5)^2/2000 = 5 million. Only a very small fraction of the nuclear mass is converted to energy via Einstein’s formula. After all we’re not talking about “Warp” engines here, just fission ones.

    • Cyril R. says:

      Yes, I was amazed to find that only about 0.1% – about 1 in a 1000 – gets converted to energy. Fissioning 1000 kg of uranium produces 988 kg of fission products, 11 kg of neutrons, and only 1 kg is actually converted to energy via E=MC2.

      A nuclear reactor really is a fission product production plant. The 0.1% that gets converted to heat is a mere minor byproduct. That’s how powerful E=MC2 is.

      • John C says:

        Cool. Now what I’m confused about, is that Steve and Rod above implied that the reaction C + O2 –> C02 causes a loss in the mass of the relative Electron clouds. Does a mole of C and a mole of O2 really weigh a smidge more than a mole of CO2?
        I don’t think so. Would there really be a mass loss equal to the energy gain of about {4eV * (Avogadro’s number)}? I’m not inclined to see chemical potential energy as mass, but only as potential energy.

        • Engineer-Poet says:

          Yes, the mole of CO2 does have some infinitesimally small mass deficit compared to the mole of C plus O2.  The energy released in the reaction isn’t created ex nihilo, it comes from the greater binding energy of the CO2 molecule.  That binding energy makes it just a smidge lighter.

          • Stephen says:

            yes, 12g of carbon and 32g of oxygen would produce not 44g of CO2 but 43.99999995 and about 0.00000005g would have gone missing. (about a billionth)

            I still prefer to think of mass loss as an EFFECT of energy production rather than the CAUSE of it.

            It’s quite a nice coincidence, but the mass loss in any 1GW thermal plant whether coal, oil, gas or nuclear is 1kg per year.

          • Engineer-Poet says:

            Oh, dear, where can the matter be
            When it’s been converted to energy…

          • jmdesp says:

            @Stephen : Why would it be a coincidence ? If the energy production is the same, you’ve just shown the mass consumed is the same.

            Actually the 10^7 difference in ratio is between the amount of mass that goes through the process, not between the amount of mass consumed where it’s 1 – 1 (at least for thermal energy).

            In other words, and as William hints above, the space needed to store the electrons involved in the chemicals reaction used in combustion is 10^7 time larger than the one needed to store the nucleons involved in nuclear reactions.

          • Stephen says:

            sorry, poorly worded.

            The coincidence I was meaning was that the mass should turn out to be almost exactly 1kg.

            You’re right, the fact that all those power plants consume the same mass is the point I’m making and not a coincidence at all.

            (ps. I missed out a zero in my previous calculation, it should be a 10 billionth of the mass not a billionth)

            Finally, if you really want to dig down to the bedrock of why nuclear energy has such high energy density, I think you’d have to say something about the relative strength of the strong nuclear force and the distance over which it operates. That, I think, is the reason why nucleons are confined to such a small space…and if you want an explanation of why the strong force is the way it is, probably need some sort of Grand Unified Theory.

  8. Campbell Sharp says:

    What I would like to see is the actual volume of waste fly-ash that comes out of the coal power stations. This is rarely discussed or shown. Where I live in Australia we are embarking on a new program to prospect for uranium and this is becoming contentious. We don’t have a problem with coal burning power stations within 10km of large urban areas, but concerned about uranium mines 50kms from the nearest centre of population.

  9. Cyril R. says:

    A typical figure is 2000 metric tonnes of PM10 per GWe-year. Assuming a decent electrostatic precipitator. So maybe 6000 metric tonnes of lung cancer causing PM10 for the 3600 MWe dirt burner, per year. This also includes other particulates than fly ash I think.

    The actual fly ash that is captured isn’t a problem. Fly ash makes for good concrete addition. Pozzolanic concretes are superiour for most concrete applications.

    It’s that 6000 tonnes of nasties that makes it through that is the big problem.

    • Engineer-Poet says:

      The actual fly ash that is captured isn’t a problem.

      Well, not unless it bursts the dikes of its landfill and floods homes, farms, forests and streams.

    • jmdesp says:

      Including it in the concrete however usually makes it slightly radioactive, often around 100Bq/kg. This is already more than would be tolerated for any nuclear waste than isn’t taken care of in a specific disposal facility.

      In fact if nuclear plant had the authorization to just dilute their waste down to 100Bq/kg, doing it would not just be much cheaper, but hardly generate more waste volume than the volume of ash generated by coal plant (OK, to be true this might require waiting 20 or 30 years, extracting Pu for MOX as well as isotopes like 137Cs for medical usage)

  10. James Greenidge says:

    Well folks, we thought it’d be a way-out off-the-wall tactic to stall or safety-proof nuclear plants out of the market, but yesterday on WNYC Public Radio (why were nuclear advocates MIA??), the (vehemently anti Indian Point) Clearwater Hudson River Alliance stated that in lieu the near catastrophic events over Russia and the recent bolite sightings over the East and South Coast, that all nuclear plants must be additionally certified as “meteoroid resistant” as they should be of “rare tsunamis”. Watch this bull noose around nuclear’s neck spread! Yea, snicker — but just how much of the public — and pols — would swallow that??

    James Greenidge
    Queens NY

  11. Michael says:

    I’ve had the chance to tour some power plants. In retrospect it seems amazing, but as part of some summer school program I went through a full utility-scale coal plant back when I was roughly age 13, I went through a university’s co-gen coal and gas plant when I was a stundent there, and, as part of a radiation-protection course got to see a BWR. That spent-fuel pool, sized for 20 years, was just amazingly small when seen in person, when you think about twenty years at about 1 GWe. I was only about age 20 then. That teeny-tiny sub-100 megawatt coal plant could fill that with ash and scrubber gypsum in probably a matter of months.

    • Rod Adams says:

      @Michael

      Thank you for sharing your personal experience of touring power plants. One of the big reasons that I have always been pro-nuclear was that I had the opportunity to tour a number of FP&L power plants when I was still in elementary school. Dad was an engineer for that company for 35 years and liked to share his work. He was not able to arrange an inside tour of Turkey Point or St. Lucie, but he did show me a lot of convincing photos that are not shared often enough with the public.

      I think you might be underestimating the time that it would take a 100 MW coal plant to fill up a spent fuel pool. My thumbrule is that a large train car load of coal (roughly 100 tons) can provide 10 MW-days of electricity. (Energy content of coal and efficiency of steam plants can vary quite a bit, and my number is on the low side of average fuel consumption, but it is round and within the range of expected values.)

      Good coal is about 10% ash, the ash content can be as high as 30%. Each day, then, a 100 MWe coal plant will produce about a train car load of ash. I’ll leave the rest of the math for homework, but it might take only weeks, not months to fill up a spent fuel pool with coal ash and scrubber gypsum from a 100 MWe coal plant, depending on the grade of coal used.

  12. jmdesp says:

    Ok, so it’s intriguing but a direct consequence of the SI system and of the random fact that (+/-3)^2 multiplied by +/- 1/3 equals +/- 3.

    c = 299 792 458 m/s, c^2 = 8.9875518.10^16 (m/s)^2
    thermal efficiency of current nuclear power = thEffNuke = +/- 0.35
    So electric Joule to thermal : Jth = Je / thEffNuke
    1 year = 3,1536 10^7 s
    1 GW = 10^9 J.s-1

    And so 1 kg => +/- 9.10^16 J
    1 GW * 1 year = 3,15.10^16 Je
    = +/- 9.10^16 Jth

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