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Earth Science

The Myth of Renewable Energy 835

Harperdog writes to this "Excellent piece by Dawn Stover about what renewables can and can't do. The sun and wind may be practically inexhaustible, but 'renewable' energy isn't. Solar, wind, and geothermal power are not fundamentally different from other energy technologies that consume finite natural resources. Good reading for anyone who thinks they know how to combat climate change."
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The Myth of Renewable Energy

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  • by jtoj ( 537440 ) on Thursday November 24, 2011 @12:02PM (#38158452)
    Renewable doesnt mean infinite.
    • by FTWinston ( 1332785 ) on Thursday November 24, 2011 @12:03PM (#38158472) Homepage
      The argument being made is that expensive and potentially hazardous materials are required to make wind turbines and solar panels.
      • by betterunixthanunix ( 980855 ) on Thursday November 24, 2011 @12:07PM (#38158512)
        Solar panels would not surprise me -- semiconductor manufacturing is not exactly eco-friendly. As for wind turbines, I cannot help but think of the kid in Africa who built them out of recycled auto parts.

        Really the question is, are these things better on the whole than fossil and nuclear fuels? I suspect that the answer is yes, although I am not an expert. Only people who live in shacks in Montana are seriously arguing that humanity can or should live without disturbing the environment at all; but we can at least try to not completely wreck the planet.
        • by Ethanol-fueled ( 1125189 ) on Thursday November 24, 2011 @12:11PM (#38158552) Homepage Journal
          You can argue that making and charging EV's just shifts the problem downstream to the power plants, many of which are coal-fired, but having all of the pollution more localized still makes a difference in the environment and quality of life.

          Just sucks to be you if you happen to live near a coal plant or an unsafe nuke plant.
          • Re: (Score:3, Insightful)

            by Anonymous Coward

            thermal plants have better efficiency than explosion engines in car.

            • by ccool ( 628215 ) on Thursday November 24, 2011 @12:54PM (#38159064)
              And it is much easier to have one good centralized filter/catalizer than many small one on a great many cars.
        • by jackspenn ( 682188 ) on Thursday November 24, 2011 @12:21PM (#38158652)
          I would argue nuclear is the best solution. It has the smallest impact and the greatest potential for recycling and reusing materials. The problem with nuclear power is the fear people have about it.
          • by betterunixthanunix ( 980855 ) on Thursday November 24, 2011 @12:27PM (#38158732)
            Nuclear power is not really renewable -- eventually all the uranium and thorium on Earth will be mined, and then we will need to start finding new sources of energy (or mining celestial bodies). I think nuclear power is part of the answer, but on its own it is not enough.

            I used to be a big fan of wind, but I am starting to lean in the direction of (properly managed) biomass these days, for the following reasons:
            1. Terrain that could not otherwise be farmed for food can be put to use
            2. Existing coal plants can be converted at relatively low cost to use biomass power
            3. The ashes can simply be spread on the biomass farming areas to replenish minerals in the soil (compare to coal ash, which cannot be used in this way)
            4. If properly managed, it is carbon-neutral or nearly so (on a reasonable timescale)
            • by JMJimmy ( 2036122 ) on Thursday November 24, 2011 @12:48PM (#38159004)

              Uranium is incredibly common and existing stocks can be rotated in. Typically nuclear plants only use 1% of the available energy in a fuel rod before swapping it out. Some plants are now recycling the older rods from 25+ years ago but few stations overall are capable of doing this.

            • by Canazza ( 1428553 ) on Thursday November 24, 2011 @12:54PM (#38159060)

              I like Nuclear Power, but it has a massive problem if it's poorly managed. Even just one cock-up can cause a major problem.
              The fear is justified, since If I know anything about the Human Race, it's that we can grossly mismanage things.

              • by drb226 ( 1938360 ) on Thursday November 24, 2011 @01:41PM (#38159534)

                If I know anything about the Human Race, it's that we can grossly mismanage things.

                Well, in our defense, we're better at managing nuclear power than any other species in the known animal kingdom.

                • by turbidostato ( 878842 ) on Thursday November 24, 2011 @01:58PM (#38159662)

                  Not at all, since the other species take the best management decision they can given circumstances: do not go nucular.

              • by robthebloke ( 1308483 ) on Thursday November 24, 2011 @01:58PM (#38159658)
                The massive problem is the long term cost of decommissioning. I was at primary school when they started decommissioning my local nuclear plant [wikipedia.org]. I'll be dead by the time they've finished.....
                That's one hell of a burden we are placing on our grand children.....
          • by ElrondHubbard ( 13672 ) on Thursday November 24, 2011 @12:49PM (#38159014)
            On the contrary, I would argue that the problem with nuclear power is that, as is becoming increasingly clear, people's fears about it are *justified*. The current installed base of nuclear tech represents an enormous and unsolved long-term problem to produce what are, on a historical scale, very short-lived benefits. We should not be creating any additional problems for our posterity to deal with.
          • by Hentes ( 2461350 ) on Thursday November 24, 2011 @12:56PM (#38159092)

            Nuclear power is the best intermediate solution. It's a finite resource, so the best we can do is to use it to buy some time until we develop effective renewable alternatives.

          • by Framboise ( 521772 ) on Thursday November 24, 2011 @01:49PM (#38159600)

            "It has the smallest impact" ???

            Fukushima and Tchernobyl come to mind of course. Do you realize that making an area like (40 miles)^2 unusable amounts to not a small cost on the economic point of view, or ruining the lives of 10'000's of displaced people is not a small nuisance?

            Presently nuclear energy is the energy method having the largest impact in the far future (~100'000 years), as the nuclear wastes will require to be watched for a long time. Do you realize that such a timespan is comparable to the total time homo sapiens existed on Earth? (The salary of a single engineer over 100'000 yr corresponds already to the total building cost of a nuclear plant).

            Can you imagine what will happen when the next global war occurs? And it will occur well before a century for sure. Each nuclear power plant will be an easy target, at the least a serious menace for those countries foolish enough to have forgot how stupid and nasty human beings may be.

        • by Luckyo ( 1726890 )

          Wind turbines are mostly built in the West. This isn't simple tech to build, and even a small deviation from norm may cause much harsher wear and tear. Incidentally, most of the costs of wind turbines aren't in making them but MAINTAINING them. As a result, skimping on manufacturing costs at the cost of increased maintenance makes no financial sense.

          This is exact opposite of most consumer products, where we largely gave up on maintenance because it's more costly then buying a new, made in [poor country on s

        • by chriso11 ( 254041 ) on Thursday November 24, 2011 @02:05PM (#38159706) Journal

          Well, I looked into the amount of water an equivalent coal-powered generator would use. It turns out 1GW of coal power uses 13500 acre-ft of water (4.4billion gal) per year, vs the 600 acre-feet for the solar project.

      • by JMJimmy ( 2036122 ) on Thursday November 24, 2011 @12:28PM (#38158752)

        Unfortunately the article glosses over the fact that far more of those expensive and [s]potential[/s] actually hazardous materials are required to make carbon and nuclear based power generating stations. It also glosses over the lifespan of those products vs their counterparts (largely because no one bothers to collate the data on all the replacement parts that need to go into existing stations). The argument has never been that these solutions are perfect, nor infinite. The argument for green tech is that it's better overall and more sustainable than what we're currently doing.

        • by siride ( 974284 ) on Thursday November 24, 2011 @12:34PM (#38158818)

          I think the real point is that we're fucked. Yes, fossil fuels and nuclear are worse, but wind/solar/biomass/geothermal won't save us either, for the same reasons. Although each individual installation may not be as environmentally or economically detrimental as a fossil fuel or nuclear installation, the fact that you have to have so many more "renewable" installations to meet the same energy needs counteracts that.

          The takeaway from this article is that we have to change our energy needs and growth model. There's simply no way to continue down this path, no matter what "green" technologies are developed. Energy isn't free. Energy production has side-effects. The only real solution is to use less and less of it.

          • by JMJimmy ( 2036122 ) on Thursday November 24, 2011 @12:43PM (#38158922)

            I don't think we're fucked just yet, we're close. Personally I think the energy debate is moot - market forces have and will determine where we get it. The real debate should be about food and water. We're headed for a very serious collapse and globalization has created conditions where the second there are food shortages, protectionism is going to rear it's ugly head and there will be massive starvation in some areas. Canada already experienced this in a small way, no starvation obviously, but when Katrina hit food shipments were diverted down south instead of to Canada - many shelves were empty for weeks.

          • by Luckyo ( 1726890 ) on Thursday November 24, 2011 @12:47PM (#38159000)

            This is a bit of doomsaying more then anything else. Burning technologies (for large plants, talking around 200MW per boiler) have really advanced with modern automation. Did you know that one of the biggest annoyances when burning things, SO2 has been largely eliminated in most modern plants that burn... pretty much anything by extreme control over the burning process? In other words, you don't even need complex filters on those anymore, the advances in the burning process itself due to computerization have made processes much less harmful to environment. This is why we talk so much about CO2 and so little about other products of burners - when we used to talk about those other products all the time before. Because the new plant technologies have virtually eliminated most of those, and those that remain are usually rendered harmless by solidifying them on the plant and not allowing them to spread into environment.

            Add to this the fact that we can in fact burn what we grow (biomass), then consider that nuclear is pretty efficient and safe and we have enough uranium and thorium for at least a millenium... we're not so fucked anymore. At least as long as we can develop fusion into workable system in a few hundred years. The only real problem that remains is upgrading the existing burner plants before they shit all over the environment with really toxic stuff (which is what is happening in China at the moment) as well as upgrading nuclear to more efficient and safe plants.

        • by newbie_fantod ( 514871 ) on Thursday November 24, 2011 @01:00PM (#38159148)

          Unfortunately the article glosses over the fact that far more of those expensive and [s]potential[/s] actually hazardous materials are required to make carbon and nuclear based power generating stations.

          Unfortunate but not surprising in an article published by the Bulletin Of the Atomic Scientists.

      • by multimediavt ( 965608 ) on Thursday November 24, 2011 @12:45PM (#38158974)

        The argument being made is that expensive and potentially hazardous materials are required to make wind turbines and solar panels.

        Yes, I got that from the article too, that using current technologies for renewable energy we will be using, potentially, a lot of non-renewable resources. The whole fallacious article is about how current technologies, unimproved over years of research and development YET TO COME, will do these horrible awful things. Indeed they will, if newer and more efficient ways of providing two megawatts of wind power [greendiary.com] aren't found, or better than 30% efficiency from solar panels [amnh.org] and internal combustion engines, [energy.gov] or maybe even less expensive ways to get power from rivers and the ocean than big dams. [pelamiswave.com] So, yeah, if nothing advances and no further research is funded then this guy's fantasy world of doom will come to pass. Let's hope others aren't as narrow minded as the author seems to be and that we will have some tremendous breakthroughs in renewable energy technologies with continued funding.

      • by Nicolas MONNET ( 4727 ) <nicoaltiva@gm a i l.com> on Thursday November 24, 2011 @12:50PM (#38159026) Journal

        Coals plants also need to be built, they also need generators that require rare earth elements, they also need plenty of steel and concrete. And not only do they obviously spew shitloads of CO2, you also need to build the roads, railways or ships and ports to carry the coal around, as well as mine the damn thing.

        So what is the argument? That since it's just merely much better, and not simply perfect, we should just give up on them?

      • by SmallFurryCreature ( 593017 ) on Thursday November 24, 2011 @12:50PM (#38159028) Journal

        Lets see. Coal. Expensive to mine from underground and a blight on the load in open mines. Nuclear material? Same issues with mining it and that love waste to get rid off. Oil? That is running out and drilling for it has proved hazardous. Mining it from tar sand is even worse then coal mining and even just transporting it ain't save.

        Funny the article doesn't mention any of that. Or for that matter that efficient generators ANYWHERE need rare earth magnets. In the end, almost all power generation needs the same kind of generator, the only difference is what makes them spin and how efficient you want them to be.

        And yes, desert water is not infinite... Greenland is a desert now? Funny. I expected them to be warmer. And less wet.

        Troll article cherry picks arguments to support its troll and ignores everything else.

        How unexpected.

        • by calidoscope ( 312571 ) on Thursday November 24, 2011 @02:04PM (#38159698)

          Or for that matter that efficient generators ANYWHERE need rare earth magnets. In the end, almost all power generation needs the same kind of generator, the only difference is what makes them spin and how efficient you want them to be.

          Large central station generators (actually alternators...) have been achieving 98 to 99% efficiency for several decades now using copper and electrical steel (no Neodymium). A larger rotor allows for more copper, which reduces the percentage of the alternators output power needed for generating the field. With a wind turbine sized alternator, the power required to maintain the field can approach 5% of the rated output, hence the use of permanent magnets (especially since the turbine is rarely producing rated output). Also note that making concrete for the foundations for the wind turbines does involve a lot of CO2 emissions - look up cement kilns.

          FWIW, the NdFeB magnet material was originally developed at General Motors.

    • by scamper_22 ( 1073470 ) on Thursday November 24, 2011 @12:16PM (#38158604)

      Almost everything is renewable. It's the cost of renewing it.

      I'm sure we could burn fossil fuels, capture the emissions from the air, send it to some plant, combine with energy and other things, and recreate the fossil fuel.

  • Don't worry (Score:5, Interesting)

    by RStonR ( 2471390 ) on Thursday November 24, 2011 @12:03PM (#38158474)
    After all, why worry when you know that global warming is good for world peace [in-other-news.com]?
    • by RoLi ( 141856 )

      As crazy as that may sound, it may actually be true. After all we talk about the medieval optimum (= warm, peace and progress) and the "little ice age" (= cold, wars and misery)

      • Re: (Score:3, Interesting)

        by radaghast ( 1672864 )

        The world is not as Euro-centric as most of our history lessons. I doubt the mass 'migration' of millions of pacific islander will do any wonders for world peace.

  • Hot tip: (Score:5, Insightful)

    by Anonymous Coward on Thursday November 24, 2011 @12:07PM (#38158508)

    Did you know that things like coal and oil came from the capture and processing of Photons, just like wind/PV/hydro does?

    Coal/Oil only seems cheap on a photon processed basis because Man didn't spend the effort and time converting biomass into the coal/oil.

  • by DontBlameCanada ( 1325547 ) on Thursday November 24, 2011 @12:08PM (#38158522)

    The author, by failing to mention the current oil-based energy strategy at all, while vilifying the alternative energy sources leaves the reader with a sense of, "the alternatives are bad, lets keep using the current infra until we come up with something better." Interestingly, nuclear energy is *not* mentioned either, positive or negative - it's completely omitted.

    I'd not be surprised if the author was either a shill for the oil and gas companies or the nuclear energy affiliates.

    • by BergZ ( 1680594 ) on Thursday November 24, 2011 @12:16PM (#38158614)
      This is an article from The Bulletin of Atomic Scientists (http://en.wikipedia.org/wiki/Bulletin_of_the_Atomic_Scientists).
      In the 50+ years that they've been publishing I bet they're sick of talking about nuclear (power, weapons).
    • by FooAtWFU ( 699187 ) on Thursday November 24, 2011 @12:27PM (#38158730) Homepage
      I disagree. He's clearly a neo-Malthusian arguing for population limits, calling for a " in which energy demands do not continue to escalate indefinitely" and highlighting California's expected population growth and how "There are now seven billion humans on this planet" before saying that we need "a way to reduce our energy consumption and to share Earth's finite resources more equitably among nations and generations".

      He does mention that "renewable technologies are often less damaging to the climate and create fewer toxic wastes than conventional energy sources." Are those the words of an oil-industry shill, or someone who cherishes the status quo?

      You note that "nuclear energy is not mentioned". But look! This is published in "Bulletin of the Atomic Scientists". The front page will supply you with nuclear-power reading if you really want it.

  • Steam (Score:5, Interesting)

    by slim ( 1652 ) <john@hartnupBLUE.net minus berry> on Thursday November 24, 2011 @12:09PM (#38158530) Homepage

    Several times, she talks of water consumed by steam turbines.

    Wouldn't any sane design condense the steam into water, and re-use it? Otherwise you're throwing away water *and* heat.

    • I remember being taught in school (which was some years ago now, and I'm too lazy to google it right now), but doesn't Iceland have several geothermal plants, which the by-products (heated water/steam) then go on to be used to heat nearby homes and provide hot water?

    • They're not practical for mobile steam engines, but they certainly are used in most nuclear plants. Those that don't are located near the sea. Not gonna run out of sea water any time soon.

    • Re:Steam (Score:4, Funny)

      by Gordonjcp ( 186804 ) on Thursday November 24, 2011 @12:42PM (#38158906) Homepage

      It's not really "lost", though. It just gets out of your local closed system and back into the global environment. If you just let all the steam go, it will float off into the atmosphere until it gets cold and all the little molecules start to miss their friends.

      There's currently about 5cm an hour of the result coming down all over NW Scotland.

  • by damn_registrars ( 1103043 ) <damn.registrars@gmail.com> on Thursday November 24, 2011 @12:10PM (#38158542) Homepage Journal
    "In this house we obey the laws of thermodynamics!"
  • Mostly just FUD (Score:4, Interesting)

    by skids ( 119237 ) on Thursday November 24, 2011 @12:13PM (#38158562) Homepage

    OP seems to be a compendium of old FUD I've read before. Yeah sure, solar panels have a limited lifetime -- about 25 years, by which time the next generation of them will make twice or more as many panels from the same amount of materials harvested by recycling them. Oh dear, solar sites need to wash panels, they'll never figure out how to make dust-resistant coatings, of course. OMG wind turbines use a lot of Nd (using the worst case of a direct drive unit) so naturally it follows that that's the only way to do it and we won't be switching to Separately Excited Syncronous or Switch Variable Reluctance gensets when it becomes cost effective to do so.

    I'll be glad when these clowns finally sell their Exxon stock so I don't have to listen to them whine any more in the face of the inevitable.

  • by bridgey655 ( 800826 ) on Thursday November 24, 2011 @12:13PM (#38158564)
    Do not let anyone tell you this drivel. "Solar, wind, and geothermal power are not fundamentally different from other energy technologies that consume finite natural resources" BS! BS I say! Check out www.thevenusproject.com
  • by Maxo-Texas ( 864189 ) on Thursday November 24, 2011 @12:17PM (#38158618)

    There are 7 billion people on the planet.

    Way too many.

    At our current energy usage growth rates, the planet is the temperature of boiling water before 2500.

    This has nothing to do with global warming. It's just a fact that as you use energy, it flows into the environment. Just like a 100 watt lightbulb also warms up the room, 7 billion people worth of devices releasing energy warm up the planet faster than it can radiate the heat into space.

    http://hardware.slashdot.org/story/11/08/02/2315207/limits-on-growth-of-energy-use-and-economies [slashdot.org]

  • A bit absurd (Score:5, Interesting)

    by Asic Eng ( 193332 ) on Thursday November 24, 2011 @12:17PM (#38158622)

    Sure materials which we need to use in order to build e.g. wind turbines are theoretically finite. They are not being used up by building wind turbines, they can be recycled if that's economically interesting. Stuff like "While sunlight is renewable -- for at least another four billion years -- photovoltaic panels are not." is just silly. We are not going to run out of sand in any plausible scenario, so that's just nitpicking.

    In any case, renewable energy refers to the energy source. That clearly sets it apart from other energy sources, and is thus a good description. There is nobody who believes the installations required to use renewables can be build without any environmental impact in terms of pollution, area use etc. That doesn't distinguish them from other installations. If people were calling renewable energy plants "impact free", fine the author would have a point. The myth the article is debunking is one which doesn't exist, however.

  • by 1u3hr ( 530656 ) on Thursday November 24, 2011 @12:21PM (#38158650)
    Interesting that the summary doesn't mention that TFA is published in the Bulletin of the Atomic Scientists. Which is a quote respectable group; but nevertheless, they have a horse in the energy race, one that burns Uranium. TFA simply counts the cost of various "green" energies, but never compares them to the costs of "conventional", or nuclear, energy generation. You're left with the impression that "green" energy is a shill, that all forms of energy are equally bad, and so you might as well sit back and keep burning oil and coal until someone invents perpetual motion.
  • by buglista ( 1967502 ) on Thursday November 24, 2011 @12:21PM (#38158656)
    It's really time to go metric guys, unless anyone can explain to me what that means?
  • by JDG1980 ( 2438906 ) on Thursday November 24, 2011 @12:24PM (#38158696)
    Who is Dawn Stover and why should we be taking her opinions seriously?
  • by gatkinso ( 15975 ) on Thursday November 24, 2011 @12:31PM (#38158778)

    Thank you Captain Obvious.

  • Er. Hmmm. (Score:4, Insightful)

    by DeathToBill ( 601486 ) on Thursday November 24, 2011 @12:35PM (#38158824) Journal

    Published in The Bulletin of the Atomic Scientists. Can't see any agenda there...

    She doesn't exactly cover herself in glory for facts, either. She doesn't appear to know what neodynium is used for (why, exactly, would you want magnets in a gearbox?). She (quite deliberately, I think) confuses consumable fuels with non-consumable equipment - a turbine may need 800 pounds of neodynium, but after 20 years of operation you've still got 800 pounds of neodynium. In fact the whole magnet is reusable as is. Today's largest wind machines are 10MW (in construction, anyway). 4.5 million of them would (on average, not peak capacity) provide the entire world's energy use - not sure where her need for an additional ~2 billion devices comes from.

    Of course it's not infinite - nothing is (probably) but that's not really the claim, is it? The only sensible point made is that renewable sources require materials that are finite, but I think we knew that already.

  • by Stirling Newberry ( 848268 ) on Thursday November 24, 2011 @12:39PM (#38158880) Homepage Journal
    A great deal more austerity. However, it makes a rather weak argument about a very real trade off problem, that problem is the water-energy trade off problem. In almost all forms of energy generation, it is not usable energy that is created directly, instead, heat is generated, the heat is used to do work, and the work is used to store the energy. So, the classic steam turbine has water heated to gas, and the resulting steam spins the turbine, and that carries wires through a magnetic field, which generates a corresponding electrical current, and that current is sent down wires. Another water energy trade off is to have wind turbines pump water up a shaft, which then is allowed to fall, spinning turbines, when power is needed. Bio-fuels, the same way: water is used to grow plants, the plants fix sunlight into hydrocarbons.

    The solution to the water energy problem is more energy, because energy can be used to get water. This, however, lowers the Life Cycle Output of the energy system. LCO or LCA is the expected usable energy out, divided by the expected usable energy used to create and run a system. So if a system produces 10 watts for every watt it takes to build, run, and dispose of it, then its LCA is 10. The 20th century got by on a miracle: namely petroleum has a high LCA, and its its own storage mechanism. Gasoline has great power to weight storage capacities with internal combustion. And internal combustion engines can be built of very cheap metals. There are many quandaries in replacing hydro-carbon energy, and the water energy trade off that the piece mentions is one of them, but it is one of scale. Once there is a large enough renewable base, then the low LCA that getting the water to run it has, is not a problem. It is at the beginning, when the return is eaten through by the water problem, because there are competing uses for water that have much higher economic returns in the short run, such as airconditioning and agriculture. None of these uses want to pay much higher rates for water so that people not yet born can have the advantages.

    Where the article falls down is pressing an agenda, and making sloppy equivalences. The first is equating capital requirements with expendable requirements: we don't burn the rare earths we use in kinetic energy extraction – that is water, wind, and geothermal – and in fact, rare earths, are not, as a percentage of the earth's crust, all that rare. For example, wikipedia has this chart [wikipedia.org]. It shows that all of the Lanthanide rare earths, plus scandium and yttrium, are more common than either gold or silver, many are more common than tin, and some more common than lead. The problem with them is that they tend to be found near the Actinide rare earths, particularly Thorium. If you have seen a press for "Thorium reactors" it is because exploitation of rare earths leads to Thorium by product, and reactors which burn it would be fantastically profitable, for the people who sell the rare earths. In reality, they have the same problems, only more so, of actively cooled salt reactors. Namely, they work until they blow up. The Chinese dump their Thorium in a holding lack, which, should it break, would contaminate large areas of land and volumes of water.

    Side note: how is it that a browser's spell check doesn't know Actinide?

    But for all of that, rare earths are not burned, the way for example Lithuium is not burned in a battery and can be recycled. These are recyclable, which is different from consumable. Hence moving from consumption of hydrocarbons, which really are burned, to using rare earths in capital energy, is a positive step, and while the author of the paper implies that there would be rare earth shortages, the reality is that this is not the case, and substitutes in the form of ceramics and active magnets (See Rare Earth Prices Plunge as Manufacturers turn to substitutes [mining.com]

  • by Kjella ( 173770 ) on Thursday November 24, 2011 @12:45PM (#38158968) Homepage

    If we burn coal, we still have carbon and oxygen just in a much lower energy state. We can't get that back without spending at least as much energy as we got out (in reality a lot more), which would defeat the whole point. Same with oil, gas and nuclear. So solar panels have a limited lifespan, but it's not like they disappear when they break down. Recycle them and make new ones, as long as you manage to get a net positive contribution of energy it's sustainable. The reason is of course that solar panels have an external power source while coal does not. Of course we have to design them to be recyclable and actually do it, but that's a matter of will and economics. But there's no way to do the same with fossil fuels, they'll never be sustainable because their energy is consumed.

  • by Jmc23 ( 2353706 ) on Thursday November 24, 2011 @01:00PM (#38159154) Journal
    It's obvious this person has an agenda as they don't take water recycling into account, whether within systems or within nature.

    However, this deals with renewable energy as touted by big business. They make big huge systems that consume lots of resources so that they can sell them and make money. A passive solar house isn't going to use all these rare precious resources. Geothermal energy that is designed into the house going down 10 to 20 feet using convection isn't going to require the same massive resources that a huge power plant going hundreds of feet into the ground nor is there any fracking required. A personal wind turbine or hydro isn't going to need rare earth magnetics to squeeze out every drop of possible energy because energy use will already be reduced and you can just take the inefficiency of normal magnets/em into account when designing the system.

    Besides the obvious slant of the article what we should realize is that large, centralized, hi tech renewable energy products are unsustainable. The way to go is smaller, decentralized, personal systems. Decentralization reduces the need for large quantities of any resource to be taken from any given area, making it sustainable. Is it a bother to have to wipe down your mirrors 2 or 3 times a year on your passive solar oil collection system, sure, but you won't need 600 acres of water in your back yard, just a damp cloth.

    Unfortunately that involves designing tech that can be put together/serviced by your average joe and that simply isn't going to happen without government or industry help to educate the masses which won't happen because there's no money in teaching a man how to fish instead of selling him a fish everyday for the rest of his life.

    Which is unfortunate. I'd love to see bamboo sand biofilm water filters with added activated carbon (provided by gov't/business) in homes for cleaning water instead of huge water treatment plants and plastic encased water filters that are non-renewable by the customer.(activated charcoal is renewable, if they let you get at it)

  • Scale (Score:5, Informative)

    by inhuman_4 ( 1294516 ) on Thursday November 24, 2011 @01:11PM (#38159272)

    The problem is not so much with the technologies' themselves as it is people's understanding of the scale of them. For example Tom Murphy [ucsd.edu] explains that dropping the great lakes by 1m would produce 54 billion kWh. Compare that to the 2,000 billion kWh produced every year by coal plants [wikipedia.org]. My napkin math says we would drain the great lakes of their current supply of water in the order of years, not decades just to replace coal.

    Since the people on Slashdot are mathematically inclined, try to calculate the physical area needed for solar panels to replace a nuclear power station near you. To replace the Pickering Nuclear Planet [wikipedia.org] (3.1GW) the oldest planet here in Ontario with solar assuming Ontario get the global average amount of sun light [wikipedia.org] (which is pretty generous for Ontario) and gets an average of 20% efficiency you get 250W x 0.2 = 50W/m^2. So, (3.1E9W) / (50W/m^2) = 62E6 m^2 or 62,000 square km, a box 8km by 8km of solid solar panels or a circle with a radius of 4.4km. That is approx 2% the size of the exclusion zone around Chernobyl. We are talking about building something 2% the size of the area we fenced off during the worst nuclear accident in history per nuclear station.

    Most renewable source of energy are not very concentrated, so anything dealing with them has to be huge, it's inescapable.

  • by dr2chase ( 653338 ) on Thursday November 24, 2011 @02:34PM (#38159926) Homepage

    It's a misleading hack piece. First, 600 acre-feet of water per year to run a 1000-MW plant is diddly-shit. For comparison, a unit-home consumes about 1kw (averaged over a month, give or take a factor of two) and one acre-foot/year of water. So a plant supplying enough power for a million homes, which themselves consume a million acre-feet/year of water, will add 600 acre-feet/yr of water to their consumption. Whoopie-shit.

    Notice how no numbers were given for the geothermal plants and their consumption. The Geysers [wikipedia.org] were initially run from in-place groundwater, which they did consume (there was no condensation, no recharge). Now they are being recharged, NOT with groundwater, but with treated sewage water. So the article was misleading there, too, since groundwater is no longer the limiting factor.

    She gives numbers for windpower resource consumption, but is again misleading. A "4-foot-wide, 7630 mile sidewalk". How do you suppose that compares to a single lane of interstate highway (12 feet wide) capable of carrying truck traffic? 636 miles of 4-lane interstate, NOT accounting for the increased road thickness. She repeats the "rare earth metals are rare" canard.

    Neodymium [wikipedia.org]: "Although neodymium is classed as a "rare earth", it is no rarer than cobalt, nickel, and copper ore, and is widely distributed in the Earth's crust". She may be right about Dysprosium [wikipedia.org], at least with current magnet technology. It's not clear if it's necessary, or merely nice at current prices. Note that the current main consumption appears to be hybrid automobiles, not wind turbines. (Hybrid autos, not a good idea at present size.)

    Her treatment of hydropower is similarly deceptive -- first dismiss newer technologies as "experimental", then hammer on the problems of (some) hydropower installations. Wave power [wikipedia.org] looks interesting. There's not too much that can go wrong with a buoy anchored to the bottom; we've got ample experience with them in their non-power-producing form.

    All of the article lacks a good "compared to what" -- how much water and concrete are consumed by existing energy production? What resources do they consume?

    So, NOT an excellent article.

  • I call bullshit. (Score:4, Interesting)

    by tombeard ( 126886 ) on Thursday November 24, 2011 @02:45PM (#38160002)

    I gotta see some backup for:
    "The gearbox of a two-megawatt wind turbine contains about 800 pounds of neodymium and 130 pounds of dysprosium "

    I've worked on a lot of gearboxes and several turbine/generator sets in my career as an ME. The gearbox on a 15MW gas turbine generator might weigh 1/2 a ton total and I assure you that is 90% iron and 10% oil. I think somebody seriously slipped a decimal point or two.

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