Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?

Molten Salt-Based Solar Power Plant 478

rcastro0 writes "Hamilton Sundstrand, a division of United Technologies, announced today that it will start to commercialize a new type of solar power plant. A new company called SolarReserve will be created to provide heat-resistant pumps and other equipment, as well as the expertise in handling and storing salt that has been heated to more than 1,050 degrees Fahrenheit. According to venture capitalist Vinod Khosla 'Three percent of the land area of Morocco could support all of the electricity for Western Europe.' Molten Salt storage is already used in Nevada's Solar One power plant. Is this the post-hydrocarbon world finally knocking?"
This discussion has been archived. No new comments can be posted.

Molten Salt-Based Solar Power Plant

Comments Filter:
  • The system's main energy source, the sun, is renewable and costs nothing.

    So Gene Wolfe was right?
    http://en.wikipedia.org/wiki/Book_of_the_new_sun/ [wikipedia.org]
    http://en.wikipedia.org/wiki/The_Urth_of_the_New_Sun/ [wikipedia.org]
    • by rustalot42684 ( 1055008 ) <fake@acco u n t.com> on Wednesday January 02, 2008 @07:09PM (#21888324)
      I got in trouble for that in grade 5 when I pointed out that the sun would eventually die out. I was told "Well, it's not going to die out in our lifetimes". I replied with "So are oil and gas renewable resources if they aren't depleted before we die?". The teacher put on my report card " ... seems to have trouble distinguishing between renewable and non-renewable resources."
      • Re:sun renewable? (Score:5, Insightful)

        by Dorceon ( 928997 ) on Thursday January 03, 2008 @06:22AM (#21892568)
        I guess the relevant terms should be exhaustable vs. non-exhaustable. Using sunlight for power doesn't change when the sun will die. Using fossil fuels for power changes when the fossil fuels will run out.
  • by AshtangiMan ( 684031 ) on Wednesday January 02, 2008 @06:36PM (#21887948)
    Don't current adsorption chillers use solar heat/ molten salt? A pretty week summary but perhaps someone out there knows how this works . . .
    • by jcaldwel ( 935913 ) on Wednesday January 02, 2008 @06:45PM (#21888052)
      I'm with you, I wanted more info. I found a page with a little more technical information about how this works: http://www-stud.fht-esslingen.de/projects/alt_energy/sol_thermal/powertower.html [fht-esslingen.de]
  • by urcreepyneighbor ( 1171755 ) on Wednesday January 02, 2008 @06:37PM (#21887958)

    Is this be the post-hydrocarbon world finally knocking?
    A "post-hydrocarbon world" has been available for a long time - nuclear. She's been knocking for so long that her hand is sore.

    While I would love to believe some form of solar power would meet the world's needs, it simply isn't feasible with current technology.

    We'll probably have wormholes, sexbots and universal prosperity before solar can meet the demand. :)
    • Ah, but didn't you hear [slashdot.org], the sexbots will meet the demand!
    • Re: (Score:3, Funny)

      by B3ryllium ( 571199 )
      With apologies to The Tick ... Fission is a harsh mistress.
    • The energy cost with refining, processing, storing and disposing of nuclear materials makes solar look like a bargain. Nuclear fanatics seem to forget the process it takes from digging up something that is one of the rarest elements on our planet and then disposing of such elements when we are done.
      • by Entropius ( 188861 ) on Wednesday January 02, 2008 @07:37PM (#21888660)
        What are you smoking?

        It requires an absolutely tiny amount of uranium to run a nuclear plant, compared to the 10,000 tons/day that a 1GW coal plant uses. Uranium is rare, but you don't actually need that much *of* it. 95% of the fuel used in fission plants can be reprocessed. Coal producers are chopping off the tops of entire *mountains* in Appalachia;

        "Disposal" isn't as big a problem as it's made out to be; reprocessing reduces the amount of waste produced tremendously, and storing a little waste for a time is a whole lot better than *not* storing it and dumping it into the atmosphere, as we're doing with coal.

        There are other forms of power generation than nuclear, but at the moment it is the only proven, scalable, clean, and economical alternative to fossil fuels for power generation. Perhaps solar-thermal (as in this article) or geothermal or tidal power or some sort of wind power can be used to carry a lot of the load, but nuclear power is available now, and the only thing lacking is the political will to implement it.

        France had that political will, and now they have the cheapest power and the cleanest air in Europe.
        • by linzeal ( 197905 ) on Wednesday January 02, 2008 @09:47PM (#21889918) Homepage Journal
          It is not just that they are chopping whole mountains off it is that there are 1000's Coal Fires [wikipedia.org] in mines underground that are adding anything from 1-5% of the worlds Co2.
        • by falconwolf ( 725481 ) <falconsoaring_2000NO@SPAMyahoo.com> on Thursday January 03, 2008 @12:15AM (#21890914)

          "Disposal" isn't as big a problem as it's made out to be; reprocessing reduces the amount of waste produced tremendously, and storing a little waste for a time is a whole lot better than *not* storing it and dumping it into the atmosphere, as we're doing with coal.

          The French, who have come the farthest in reprocessing, are finding out it's not as simple to reprocess as many would have you believe. IEEE's magazine "Spectrum" has a good article on this: "Nuclear Wasteland" [ieee.org]. However another /.er brought up the Candu [wikipedia.org] reactor in Canada a few weeks ago. I don't know much about it so I can't say whether there are any problems with the design or waste, or whether its economically feasible. However nuclear power isn't really needed, not in the US. The Rocky Mountains [nrel.gov] alone contain enough potential wind power to supply the 48 continuous states with electricity. Add OR, CA, AZ, NM, and Texas along with some offshore sites from Cape Cod to the Mid Atlantic and much more can be generated by wind. Also many megawatts of potential power goes up smoke stacks daily as Waste Heat [enn.com]. Combining wind, solar power, cogeneration or waste heat recovery [csiro.au] and conservation negates the need for nuclear power. The alternative power sources, both listed above and others, have a distinct advantage over nuclear power, while it can take years and years for a nuclear power plant to be constructed and brought online, these others can be added immediately. Wind generators and solar PVs can be made from raw material and brought online in months, and can be sited closer to many of the placed where the energy is needed. Besides PVs on roofs a farmer in the Adirondack Mountains [adirondackwind.com] in New York can provide electricity to NYC. The farmer would then have a second source of income.

          • Re: (Score:3, Informative)

            by Phanatic1a ( 413374 )
            The French, who have come the farthest in reprocessing, are finding out it's not as simple to reprocess as many would have you believe. IEEE's magazine "Spectrum" has a good article on this: "Nuclear Wasteland"

            That article doesn't support what you claim.

            The French experience clearly does show that reprocessing need not be the dangerous mess that other countries, including the United States, have made of it [see photo, "Blue Glow of Success"]. The U.S. military used reprocessing for several decades to separa

      • Re: (Score:3, Insightful)

        by Mark_MF-WN ( 678030 )
        Anti-nuclear cowards seem to forget that nuclear power's main alternative -- coal -- requires destroying vast swaths of land to extract, and releases far more radioactive waste into the atmosphere than nuclear releases into manageable steel drums.

        I know that YOU probably enjoy acid rain, mercury poisoning, and the pulmonary disorders that are inextricably linked to the emissions from coal plants, but I don't. Meanwhile, nuclear plants produce well-contained waste that can be reprocessed, and use tiny amoun

    • Re: (Score:2, Informative)

      by soul_well ( 1143717 )
      Not so. Solar is closer to meeting our needs than you may realize. Nanosolar has been in the news recently for producing its first runs of third generation solar panels. These are essentially printable sheets of foil that are cheap and easy to produce.

      The NYT quotes Nansolar's founder and CEO Martin Roscheisen saying, "With a $1-per-watt panel, it is possible to build $2-per-watt systems." That $2-per-watt figure comes from the Energy Department, the cost of building a new coal plant.

      source [infoworld.com]

      The futu

      • by Anonymous Coward
        when the sun is out, and Wind is great when the Wind is blowing, but they are not viable for providing base load power [wikipedia.org] needs.

        Nuclear is ideal for providing base-load power (30-40% of peak capacity), suplemented by Solar, Wind and Tidal power.
    • While I would love to believe some form of nuclear power would meet the world's needs, it simply isn't feasible with current technology.

      There are some promising possibilities (pebble bed is at an advanced stage now, and accelerated thorium shows potential) but TRY PAYING ATTENTION - Iran and North Korea's efforts have been headline news for some time and should highlight that what we have today is a dual use compromise that could be better. If the focus was primarily on electricity generation like some of

    • by jcaldwel ( 935913 ) on Wednesday January 02, 2008 @09:10PM (#21889604)

      While I would love to believe some form of solar power would meet the world's needs, it simply isn't feasible with current technology.

      Much of the argument against solar is one of economics, but a company called Nanosolar has recently produced solar panels making energy more cheaply than coal. [grist.org] "Current Technology" is a moving target.

  • by thule ( 9041 ) on Wednesday January 02, 2008 @06:38PM (#21887970) Homepage
    " Is this be the post-hydrocarbon world finally knocking?".....

    It was here 50 years ago with nuclear power. Thankfully, it's finally getting attention again.
    • by BlueParrot ( 965239 ) on Wednesday January 02, 2008 @06:52PM (#21888148)
      On a related note, nuclear engineers were using molten salts decades ago, and even developed a special corrosion resistant alloy, Hastelloy-N, to deal with the corrosion problems. However, the molten salt system turned out to be more expensive than water based technology, thou this may change if thermochemical production of hydrogen kicks of.

      Essentially, proponents of solar power usually like to fantasize about theoretical advances in solar technology, while simultaneously refusing to recognise advances in nuclear technology. As an example, electric cars are usually touted as being CO2 neutral "if the electricity comes from renewables". It is outright obvious that this remains true with nuclear as well, but that is scary and hence rarely mentioned. Similarily advances in electric storage is usually touted as a means of allowing solar to be used for baseload, but rarely is it pointed out that the same tech coudl allow nuclear to deliver peak-energy at increased efficiency by running the plant at its maximum output even when demand is low.

      • by stomv ( 80392 ) on Wednesday January 02, 2008 @07:15PM (#21888414) Homepage
        1. Nuclear power is not carbon neutral. Uranium is mined, and nobody is running mining equipment on biodiesel, nor are they transporting it to power plants using biodiesel, ethanol, or even renewable generated electricity on electric locomotives. To be sure, the amount of carbon is extremely low per kWh of electricity generated, but very small > 0, even for very small cases of very small.

        2. As you know, nuclear proponents continually ignore the major immediate problem with nuclear power -- waste storage. Nobody wants more glass-encased nuclear waste in their neighborhood, and presently nobody wants some other neighborhood's nuclear waste being transported through their neighborhood. The nuclear industry has got to find technical and political solutions to these problems before society will embrace nuclear as a green solution. I'm not arguing that burning coal or oil is safer or cleaner than nuclear, just that any change to a status quo requires more than a slight or obscured imbalance, which is how the public currently perceives the status quo.

        3. What is Hubbart's Peak for uranium? I have no idea, but it surely must have one.

        4. Which nations have substantial amounts of useful uranium? What would the balance of power be if those nations became the new Saudi Arabia of energy?

        5. Solar off-peak is simply not a problem, not for a long time. Peak demand is highly correlated with sunshine in most of the world -- solar could serve quite effectively as the peaking plant, relying on other types of generation for base load. Electric storage is just not a major issue for solar -- it might become one for wind but it wouldn't be that hard to operate other green energy plants in a negative correlation to wind, ie burn woodchips when the wind isn't blowing, but not when the wind is blowing.

        6. That said, plug in cars might change that formulation substantially, since most people would plug in their cars at night thereby adding demand off-peak [and off-sun]. If/when that happens, much of (5) becomes moot and there'd be some shifting of nighttime use [industrial, it's cheaper] to daytime and there'd be encouragement for folks to charge during the day [plug in jacks at car parks] to help keep demand during the day higher, when production due to solar is higher.

        7. Ultimately, this doesn't matter. Solar production in the US is well less than 1%. Even at 10% there won't be a necessary substantial change in infrastructures or demand shaping. So, until then, more of every kind of renewable electricity generation is better, and none of it will create challenges. And, of course, nuclear may or may not be greenish, but it is not renewable.
        • by Rei ( 128717 ) on Wednesday January 02, 2008 @07:34PM (#21888610) Homepage
          3. A long, long way away when you consider seawater extraction, and even further with breeders, incl. thorium. Sure, it's quite expensive in comparison to mining, but the cost of fuel isn't the real cost in nuclear power -- it's paying for your reactor construction and decomission that kills you.

          4. Ignoring seawater? Australia by far, at 24% of known reserves. Other significant sources include Kazakhstan, Canada, South Africa, Namibia, Brazil, Russia, the US, and Uzbekistan.
        • by radl33t ( 900691 ) on Wednesday January 02, 2008 @07:45PM (#21888754)
          A commonly employed tactic, you have just narrowed your scope such that you can criticize nuclear energy. 2. Not a problem. More people would understand this if fear hadn't reigned and nuclear research didn't take a nose dive decades ago. 3. Also not an imaginary problem. Proper (well documented) reactor design will eliminate this concern. IT would be a done deal if we maintained the nuke program from the 60s through today. Even existing tech would allow us to burn other elements, which are more plentiful than uranium. On second thought, why aren't you concerned with Hubbert's Peak for the sun or the universe? The timescales of these peaks are not really of a concern same as those for uranium, unless you really think you can plan for 100+ generations out. 4. There is enough unused "waste" sitting around for thousands of years. Plenty hiding around down under too. 5. Actually the lack of off-peak energy is a massive problem, mostly for economic reasons. IT is probably the single largest cost barrier for both wind and solar, which typically enjoy moderate to peak output less than 20% of the time. In other words, to reach cost parity with coal they actually need to be 5 times cheaper. 6. Ultimately it doesn't matter? Um, yes of course if you are so narrowly focused that you don't consider things like economies and social welfare. Why isn't nuclear renewable? Just as renewable as our sun if you ask me. p.s. pv isn't carbon neutral either p.s.s. Life is destructive. take it or leave it. Don't kid yourself. Nuclear energy is at least as good an option as solar or wind for decades. At least until fancy PV arrives at 100s of GW of annual production. But then again theres no difference between fear of nuclear energy and whatever other boogieman is out there.
        • by sholden ( 12227 ) on Wednesday January 02, 2008 @07:54PM (#21888850) Homepage
          1. Solar cells are made from silicon, which carried in trucks and hence not carbon neutral. Every power source is not carbon neutral since it has manufactured components that were transported at some point. Of course once you have plentiful power from the nuke plants you might change that...

          2. It'd be mighty expensive but you could just mix it back with the non-uranium rock you dug out and put it back where you found it... A lot of that waste also isn't waste, it's fissionable material that politically isn't used (because doing so gives you plutonium easily used in weapons).

          3. In 20 years we'd run out if we just used uranium in nuke plants for all our electricity. Again allow breeding to plutonium and it turns into 2000 years...

          4. The top 5 known recoverable uranium holders are: Australia, Khazakhstan, Canada, USA, South Africa - they make up about 2/3rds of the total. From a Western world perspective, that's a much nicer set then the oil top 5: Saudi Arabia, Canada, Iran, Iraq, Kuwait...

          • by sploxx ( 622853 ) on Wednesday January 02, 2008 @08:25PM (#21889144)
            1. Solar cells are made from silicon, which carried in trucks and hence not carbon neutral. Every power source is not carbon neutral since it has manufactured components that were transported at some point. Of course once you have plentiful power from the nuke plants you might change that...

            And to further elaborate on this: There is this concept called Energy Returned on Energy Invested [wikipedia.org]. (And even more refined indicators).

            I have heard this flawed argument against nuclear power so often that it is not really funny anymore.

        • by Bender0x7D1 ( 536254 ) on Wednesday January 02, 2008 @08:27PM (#21889164)

          I would encourage you to read up on nuclear power - while a lot of what you are saying is true, it really doesn't capture the reality of the situation.

          1. No, nuclear, by itself, is not carbon neutral. However, neither is any other alternative energy. However, when you have the extra electrical power, you can construct "factories" that will scrub the carbon dioxide out of the atmosphere. Now, we might not have the political will to carry it out, but nuclear alone is still way better than what we have now.

          2. Fast breeder reactors can run on our current nuclear waste and the waste from those reactors doesn't last nearly as long. So we get to reduce the amount of waste and what's left doesn't last as long. The reason we don't use them is that reprocessing can create weapons-grade plutonium. Again, this is a political issue instead of a technological one.

          3. With today's "wasteful" reactors using Uranium-235 it is estimated between 80 and 300 years. If we use breeder reactors so we can use U-238 and Thorium, it can be billions of years at current energy levels.

          4. If necessary, fuel can be extracted from sea water making it a moot point.

          5. There is also a peak in the evening when everyone turns on lights and TVs. Also, winter means a lot less sunlight in many populated areas so more demand for lighting and heating.

          6. Moving power around might help, but there are just too many hours when power is needed and solar isn't available. Also, cloudy days affect production and can't be planned around. Limiting solar farms to areas with minimal cloud cover means increased losses from transport.

          7. Nuclear doesn't have to be renewable if we have a few billion years, (or even a few million), years available. If we can assume a technology level that can protect us from extinction due to an asteroid or comet in that time period, we can assume a technology level that can mine the moon, mars or asteroids for more nuclear material.

          While nuclear has its problems, they are really political instead of technological. I really hope we get past our fears of nuclear power so we have a chance of keeping our planet habitable for humans.

      • Re: (Score:2, Interesting)

        That is true, that molten salt is more expensive, but look at the overall picture. Although the working fluid is more expensive than water, water has this pesky habit of undergoing phase change, and pressures are MUCH higher. This means the cost goes into transporting the water/steam and even pressurizing whole structures, and ultimately it gets pretty hairy.

        Molten salt, on the other hand, if chosen well, will not expand as it heats/cools and can flow slowly, reducing the engineering hassle for a reactor
    • Re: (Score:3, Interesting)

      by jonwil ( 467024 )
      Unfortunatly, nuclear power will never be as good as it could be as long as the energy companies are not allowed to use technologies like breeder reactors and reprocessing because one of the steps just happens to produce something that could be used in a nuclear bomb if the wrong people got their hands on it.

      Of course, the same people forget to mention that a breeder cycle with reprocessing will produce less waste that needs to be stored.
    • Re: (Score:3, Interesting)

      by greg_barton ( 5551 ) *

      It was here 50 years ago with nuclear power. Thankfully, it's finally getting attention again.

      Back in 1960 my grandfather patented [google.com] a fuel creation process for molten salt reactors while working at ORNL. These days my uncle is carrying the torch [blogspot.com] for green nuclear power, and fighting the good fight to get people to accept it as a viable power alternative. It's an uphill battle. Folks on the left are terrified of nukes. Folks on the right are in bed with the oil and coal industries. Thankfully the technol

  • Waste salt (Score:5, Funny)

    by Threni ( 635302 ) on Wednesday January 02, 2008 @06:38PM (#21887974)
    I hope they don't start dumping waste salt in the oceans...
  • Is this be the post-hydrocarbon world finally knocking?"

    Only available in locations where ebonics be the #1 language suckah!

    On a more serious note, 3% of Moroccos land mass could provide power for ALL of Western Europe? Can I ask what possible reason there could be beyond corruption and greed for this NOT to be used? Somehow I think that this kind of technology, no matter the initial cost, would be an absolute boon and can see no reason why it shouldn't be adopted.

    Pollution form fossil fuels will be significantly reduced. We can finally move, at least o

    • by Rob Riggs ( 6418 ) on Wednesday January 02, 2008 @07:04PM (#21888262) Homepage Journal

      On a more serious note, 3% of Moroccos land mass could provide power for ALL of Western Europe? Can I ask what possible reason there could be beyond corruption and greed for this NOT to be used? Somehow I think that this kind of technology, no matter the initial cost, would be an absolute boon and can see no reason why it shouldn't be adopted.

      Well, according to the article it is being used and will be used more in the future. The issue is that it takes time, money and a lot of land (3% of Morocco [cia.gov] may seem small (446,300 km^2 * .03 = 13389 km^2), but it's larger than some European countries (think countries that start with the letter "L") and about 1/3 of the size of the Netherlands.

      It may take Hamilton Sundstrand and others quite a few years to ramp up production to the point where they can consider converting even 100 km^2 of land over to solar energy production.
    • by vijayiyer ( 728590 ) on Wednesday January 02, 2008 @07:13PM (#21888388)
      Except that you can't easily get electricity from Morocco to Europe. Transmission of electricity isn't lossless or free.
  • I am be (Score:4, Funny)

    by mi ( 197448 ) <slashdot-2017q4@virtual-estates.net> on Wednesday January 02, 2008 @06:38PM (#21887980) Homepage Journal

    Is this be the post-hydrocarbon world finally knocking?

    Slashdot editors are be the worst ever...

  • SciAm article (Score:2, Informative)

    Yes, hot salty, um, fluid is real solution to the world's energy problems. There is an excellent article in Scientific American about it in the latest issue.

    http://www.sciam.com/article.cfm?id=a-solar-grand-plan [sciam.com]

    Unfortunately, it will take massive investments to make this stuff really viable. Fortunately, some European governments are stepping up with real money. Unfortunately, America hasn't for about a decade.
    • The vast majority of the RD that has been done in alterantive has been in America. EU is simply stepping up to bring the RD to production. Even now, the top Solar Cell work is still from silicon valley, silicon mountain, even new york. The concept of using salts was RD by boeing in 2001, with about a dozen companie here already working with it. What is NOT happening is that W. is not pushing Alternative or even Nukes to any large degree. But all the VC is abuzz here. And there is LOADS of money flowing ther
  • by WindBourne ( 631190 ) on Wednesday January 02, 2008 @06:42PM (#21888018) Journal
    There are a number of companies doing this. One is looking to work in conjunction with POwer plants esp Nukes. The waste heat can actually kick the salts up a bit, and then solar pushes is that much higher. The nice thing is that this can be used on really hot days as a means of cooling off the waste heat from the nuke prior to putting in streams. Where this might get really interesting is to combine with geo-thermal power. The same sets of solar concentrators can be used to kick up heated water/steam from the ground and make the generators more efficient. During the daytime, the generators can run at full tilt, while at night, when it is just geo-thermal, then generators run at less efficient speeds.
  • by MichaelCrawford ( 610140 ) on Wednesday January 02, 2008 @06:42PM (#21888022) Homepage Journal
    Nuclear reactors can be made smaller and more efficient if they use liquid sodium for cooling. I think this may be because they can run at a higher temperature, which is more harmonious with the laws of thermodynamics.

    But the US Navy refused to build any sodium-cooled submarine reactors. Finally a Congressional committee hauled Admiral Rickover in to a hearing to testify as to why he wasn't making better use of taxpayer's money.

    To which he replied "This is what happens when sodium gets wet," and he threw a chunk of sodium into some water.

    • Re: (Score:3, Informative)

      by MBCook ( 132727 )

      There WAS a liquid sodium reactor in the US. The seals in the cooling system seals started to fail leading to severe consequences. See Wikipeida [wikipedia.org].

      • The first US nuclear power reactor (EBR-1) was a liquid-metal cooled breeder reactor, as was the Fermi 1 reactor near Detroit, Michigan. The Fermi reactor had a minor meltdown accident in 1963. Overall, the safety record of liquid-metal reactors hasn't been particularly impressive, at least in the power-generation arena.
    • by BlueParrot ( 965239 ) on Wednesday January 02, 2008 @07:07PM (#21888304)

      To which he replied "This is what happens when sodium gets wet," and he threw a chunk of sodium into some water.

      Care to guess what happens when 300 C warm and radioactive water goes from 15 mega pascal to neutral pressure within a fraction of a second after a coolant pipe bursts? No matter if it is sodium or water primary coolant leaking is a Bad Thing (tm) , and sodium has the advantage that you don't have to keep it under pressure, thus reducing the chance of a leak greatly.

      In addition sodium is practically non-corrosive to steal, while boric-acid spiked water at 300 C is quite agressive. Sodium also has a much better heat conductivity than water, so the reactor won't melt down if the primary cooling pumps fail ( natural convection of the coolant is enough to cool the spent fuel once the chain reaction has stopped, as it will do due to thermal expansion of the fuel rods ).

      Having said this, my favourite candidate for coolant is molten-lead. Like sodium you don't have to pressurise it, it doesn't react with water or air, it won't boil even if you overheat teh ractor so much that the steel melts, and it is an excellent radiation shield against gamma-radiation. Main issue is corrosion, but 20+ years of research has produced alloys that are very stable in molten lead, so you could expect comercial plants using it within a deacde or two.
    • So let me get this straight. They were afraid of the sodium getting wet, supposedly because the submarines could leak. But the fact that they had poisonous radiactive isotopes aboard didn't bother them? I mean, if they could prevent the radioactives from leaking out, they could prevent the sodium from getting wet. If they couldn't prevent the sodium from getting wet...
    • by Rob Riggs ( 6418 ) on Wednesday January 02, 2008 @07:18PM (#21888448) Homepage Journal
      You admit that it's somewhat OT, but did you also know it's mostly BS?

      Two competing concepts for cooling nuclear submarine reactors were available, cooling by pressurized water and by liquid metal. Rickover wanted to try both of them, so he arranged with Westinghouse in 1949 to investigate the pressurized water approach, and with General Electric in 1950 to pursue a liquid sodium approach.

      Rickover's faith in nuclear submarines was vindicated in January 1955, when the USS Nautilus reported that it was underway entirely with nuclear power. The Nautilus employed the pressurized water method of reactor cooling. The Navy's second nuclear submarine, USS Seawolf, was powered by a reactor using liquid sodium.
  • Are we going to get interesting comments about the technology in use here? Is it practical? Why is molten salt used instead of something else? Isn't that dangerous? Can't birds get zapped if they fly too close to the collector where thousands of mirrors are pointing? Do we even care? Why is it so expensive to build an array of a bunch of mirrors and a collector? Is it dangerous to be near this thing, where I suppose you could be blinded if you glanced in the wrong direction?

    Or are we going to just ge
  • >>> The technology was developed by Rocketdyne, which was acquired by United Technologies Corp., Hamilton's parent company, in 2005. Rocketdyne is the prime contractor for electric power systems on the International Space Station.

    This sounds suspiciously close to YoYoDyne. You know, the ones who diverted funds from the vital U.S. Truncheon Bomber program into a private project back in the '80's.

    We need to send a crack Congressional investigator to look into this immediately!
    • Re: (Score:3, Informative)

      While I'm sure your post was in joking fashion, Rocketdyne was the company who made the five F-1 motors in the first stage of the Saturn V.

      I know, I know... why ruin jokes with facts! Why, indeed - I'm an ass. That's why!
  • by Kuukai ( 865890 ) on Wednesday January 02, 2008 @06:44PM (#21888038) Journal
    If you're more interested in the technology, try looking at this [news.com]. It doesn't work "like a hydroelectric plant." (spinning a turbine doesn't = "hydroelectric") It simply uses an array of mirrors to aim sunlight at salt and heat it. The molten salt can then be used to steam water and turn a turbine, or saved for later.
  • by compumike ( 454538 ) on Wednesday January 02, 2008 @06:44PM (#21888040) Homepage
    Any system that does a thermal -> mechanical conversion is limited by the Carnot efficiency [wikipedia.org]. This system would be limited by the temperatures of the hot side (sun's heating of the salt, balanced with losses from the pipes) and the cold side (presumably atmosphere or a cold river). In contrast, a solar cell directly rectifies electromagnetic field energy (light), so it doesn't obey the Carnot limit. That's why for a system like the one in this article, there's a need to push the operating hot-side temperature up as much as possible.

    Educational microcontroller kits for the digital generation. [nerdkits.com]
    • Re: (Score:3, Informative)

      by GameMaster ( 148118 )
      That will only matter if we actually manage to develop, and mass produce, photovoltaic cells that reach anywhere near the efficiency of traditional heat engine generator facilities at a reasonable price per watt over the life of the panel. Much like the fuel cell, we've had the photovoltaic technology for a very long time and have yet to produce any truly efficient products that weren't extremely high priced specialty items for things like satellites and such. It would be great if we manage to come out wi
      • by Rei ( 128717 ) on Wednesday January 02, 2008 @08:29PM (#21889186) Homepage
        Huh? Have you compared what people were paying for solar cells back in the 70s to what they are now? And even today's prices are inflated by manufacturing shortages (the market isn't stable). If manufacturing actually met demand, we'd be paying about $3/W today, not $4.80/W. And this ignores CIGS production like NanoSolar's that's just now coming online. NanoSolar claims $1/W would still be profitable for them. The other CIGS manufacturers also (quite reasonably) anticipate very low production costs. Sure, indium is rare (about as common as silver), but you only need a tiny amount of it.

        As for the necessity of high efficiency, it's not neccessary. Even if just a small fraction of the world's urban area was paved with inefficient solar cells, it'd still power the world. I don't care to repeat this calculation yet again (I do it about once a month it seems), but look up China's total urban area (just China's) and do the math with 10% efficient cells (less than NanoSolar's) at, say, 20% coverage and an average 100W/m^2, then compare that to the entire world's electricity demand.

        As for what potential efficiency we're capable of, it's actually looking up. But not for CIGS -- for more conventional semiconductor cells, which aren't likely to be cheap enough to panel the world. We're up to a staggering 42.8% now (Honsberg and Barnett) -- and the record keeps growing at a rather surprising clip. And there's more potential for that number to keep growing up to 60-70% or so. There are three technologies pushing this -- the ability to get multiple electrons out of a single photon, the use of integrated beam splitters so that different parts of the cell can be optmized to specific parts of the solar spectrum, and the use of phosphor coatings that can be excited to release photons in a desired energy range. These technologies may not end up running our grid, but they'll be running our satellites, our malibu lights, our self-illuminated highway signs, and so forth.

        Back to the initial topic: Just to drive home the point as to how much photovoltaic prices have been dropping, let's put in some historical price points (in non-inflation-adjusted dollars):

        1956: Bell solar cell: $300/W .
        Early 1970s: Bergman's improvements lowers the price from then $100/W to $20/W

        Specifically [unu.edu] (in 1994 dollars):
        1976: ~$51
        1977: ~$38
        1978: ~$27
        1979: ~$21
        1980: ~$18
        1981: ~$15
        1982: ~$14
        1983: ~$11
        1984: ~$11
        1985: ~$10
        1986: ~$9
        1987: ~$8
        1988: ~$8
        1989: ~$8
        1990: ~$8
        1991: ~$7
        1992: ~$7
        1993: ~$6
        1994: ~$6

        In non-inflation-adjusted dollars, solar prices were at a minimum in the early '00s (~4$/W, if I recall correctly), and rose up until this summer due to supply shortages, when they started to go down again. And with the CIGS companies, the prices can be expected to go down a lot over the next several years. Anyways, I really don't see how anyone can look at the numbers and act like solar hasn't been advancing by leaps and bounds since it was first turned from a laboratory curiosity into a commercial product in the '50s.
  • by tempest69 ( 572798 ) on Wednesday January 02, 2008 @06:45PM (#21888056) Journal
    The concept is this.. The power company auctions off power in real time to devices which automatically bid for "cheap energy blocks" The cheap energy blocks never exceed the price of standard energy. This allows the power company to adjust load based on production from non-predictable sources. So when a windfarm starts going crazy with power, the air conditioner in your house can go full steam for quarter price. As the number of smart devices increases, the prices can auction to higher values. As smart devices get more vogue, we can rely on sporadic power generation more and more. Right now, the power companies predict usage, with little control, with smart energy, they can tune usage much more efficiently.

    The concept of storing the energy as thermal is fine, but reducing the amount of energy swaps is going to be the more efficient way to use the power. The efficiency that they can store energy and re-convert it is going to determine how low a cheap power block can sell for.

    Anyway, just a crazy rant.. enjoy,


  • The claim seems exaggerated, but works: wiki tells me Morocco has 446,550 km2. crunching the numbers, 4% at 100% efficiency only gives 5.8 TW, or 19 kW per capita.

  • is that if vinod is going to build the equipment to handle the salts, he might be making these not just large, but also small ones. By building small ones, it will enable distributed storage. That may not sound that useful, but it is just parallelism for storage; Makes it much more resilient; can be used to power the local area, useful for disaster times, such as 9/11, katrina, snow falls, etc. it allows for small start-ups to be created that store the power at night (say at 1 penny, but put it back k on th
  • by LWATCDR ( 28044 )
    "Is this be the post-hydrocarbon world finally knocking?" No.
    What it may be is a good start at ending the use of hydrocarbons for electrical power generation. Throw in some Wind, nuclear, some photovoltaics, some hydro, and maybe some biomass and you could reduce our use of coal, oil, and natural gas for power generation a lot.

    This is one of the first good energy storage systems I have heard about. Yes it could really help with making solar thermal power a lot more practical.

    For transportation I think we w
    • by tsotha ( 720379 )
      If energy is cheap enough to make hydrocarbons, then we can make hydrogen and dispense with the unwanted byproducts. Or do you mean to say we can make hydrocabon fuels directly from atmospheric carbon?
    • It looks like Hydrogen Fuel Cell Hybrids are the wave of the future.

  • I thought it was sodium heated to a liquid state. Not "Molten Salt".
  • Molten salt? Wowee!

    Let's do the math, folks.

    Presuming you want to melt salt, you probably need a whole lot of mirrors. Compute the cost of a square meter of mirror, one that will last for twenty years. Now add the cost of a mirror support, one that will keep it aimed at the collector. The sun moves, so you'll need a aiming device. Estimate the cost of an aiming device that can last for say twenty years and survive typical weather conditions over twenty years. Don't forget wind gusts!

    I suspect you'

    • I somehow missed the math in all that generalized ranting.

      The real problem is economics, however. Not necessarily in the way you mean because this is actually relatively robust and proven tech, but economics none-the-less.

      People aren't going to get behind it because it would involve a lot of new taxes. Industry isn't going to get behind it because fossil fuels are still cheap(er than alternatives), and the infrastructure around them is well established and proven. The government isn't going to get behind it
    • You are right about the mirrors. I am about 2 hours away from a solar generation plant here in California and when you drive by the plant you notice that a good 10% of the mirrors are broken or have peices missing. I'm sure this will go up with time so it will cost money to keep it in good working order.
    • by FroBugg ( 24957 )
      Because fossil fuel power plants don't have any costs associated with them?

      Considering the costs of construction, fuel, operation, and everything else associated with the production, current operating solar plants produce energy at just three to four times the cost of fossil fuel plants, and this price is steadily coming down.

      Your suspicion of a factor of thirty is wrong. By a factor of ten.
  • 'Three percent of the land area of Morocco could support all of the electricity for Western Europe.'

    1. Find a resource that'll support western Europe that's outside of western Europe.

    2. Do they have a flag? No? Then they can't have a country.

    3. Profit.

    The only difference is that this time, we British will fight to the death to defend anyone who can also help make our chips* a little saltier.

    *Note: No, "Chips" are not "Fries" for Americans. What Americans call "Chips", the English call "Crisps", certainly. However, what the English call "Chips", Americans call "What the hell is that greasy thing? It's goi

    • Re: (Score:3, Funny)

      by Bryansix ( 761547 )
      British people are totally backwards. For proof look at their use of "Fanny Fun" to refer to straight sex between a man and a woman. The only Poofters are the ridiculous people who use such a word.
  • Three percent of the land area of Morocco could support all of the electricity for Western Europe.'

    Great from an environmental perspective, unless you are a Moroccan. However it sounds even worse with respect to foreign dependence on energy. At least there are multiple countries/regions to buy oil from. If you out source your solar farm you are in a crisis as fast as someone can throw a switch.

    How about each EU member commits 1% of its own territory (roofs count), to the EU power grid. The EU has 10
  • Looks like they will use simple plane mirror heliostats to concentrate the radiation to boil water to run steam turbines. Excess heat will be used to melt salt and store it underground and that heat will be drawn during the night and overcast days. Looks like it is a question of break even periods and investment costs. But so is every solar plant of every technology.

    Still our transportation sector still relies too heavily on imported oil and this technology too would not do much to alleviate it, by itsel

  • ``Is this be the post-hydrocarbon world finally knocking?''

    I think it already was a matter of will, not technical ability.
  • Is this be the post-hydrocarbon world finally knocking?

    I can has bad grammar??
  • Articles on massive scale solar power systems almost inevitably include some sort of a comparison showing that solar power generation is not cost-competitive with systems which burn oil or natural gas as fuel. The implication is that solar systems will force consumers to pay more for electricity, thereby discouraging their construction.

    There are two critical issues that such cost comparisons ignore:

    1) They never account for the long-term costs of pumping more carbon dioxide (plus various pollutants) into t
  • by John Sokol ( 109591 ) on Wednesday January 02, 2008 @07:06PM (#21888292) Homepage Journal
    I will just dump a mess of links from an old E-mail I did on this some time ago. It's all good stuff, Solar two in Mojave was also molten salt based. I knew someone who bought it after it failed and got to explore it before it was partly dismantled.


    Solar two was a flat mirror array.

    Search google image search with
                "solar two" Mojave

    http://maps.google.com/maps?f=q&hl=en&geocode=&q=yermo,+ca&ie=UTF8&ll=34.871919,-116.83416&spn=0.005915,0.010042&t=h&z=17&om=1 [google.com]

    Take the link above and zoom out, just below and to the right is a Parabolic glass mirrors plant

    http://en.wikipedia.org/wiki/Solar_Two [wikipedia.org]

    http://www.powerfromthesun.net/Chapter10/Chapter10new.htm [powerfromthesun.net]

    http://en.wikipedia.org/wiki/Image:Solar_Two_2003.jpg [wikipedia.org]

    http://en.wikipedia.org/wiki/Image:Solar_Two_Heliostat.jpg [wikipedia.org]

    http://theothersolar.com/?m=200702 [theothersolar.com]

    http://www.commondreams.org/headlines06/1101-10.htm [commondreams.org]

    http://www.global-greenhouse-warming.com/solar-central-power-towers.html [global-gre...arming.com]

    http://www.ldeo.columbia.edu/edu/dees/U4735/projections/pitman/solar.elec.jpg [columbia.edu]

    http://fixedreference.org/2006-Wikipedia-CD-Selection/wp/s/Solar_power.htm [fixedreference.org]
    (search for "Solar two")

    http://www.reia-nm.org/HTML_Docs/Solar_Thermal_Electrical.html [reia-nm.org]

    http://greatgreengadgets.com/gadgets/category/solar/ [greatgreengadgets.com]

    http://www.answers.com/topic/solar-thermal-energy [answers.com]

    http://blogs.business2.com/greenwombat/2006/week44/index.html [business2.com]

    Excellent page on many technologies - Sorry it's in Spanish.
          http://g3nergy.blogspot.com/2006_11_01_archive.html [blogspot.com]
          Search for "Australia to Build 154 MW Solar Energy Plant"
          This one is identical in design to the one in the Mojave Dessert here.

    http://ludb.clui.org/ex/i/CA4965/ [clui.org] Abandoned Solar Power Plant
  • Few details in the link indicate how the plant will produce power. The Nevada plant uses a steam turbine so I assume that this plant does the same. But what about using a heat engine in place of a turbine? There was a story on /. a while back about using sterling engines in a solar plant. They talked of placing a small sterling engine at the center of a large parabolic dish - sounded interesting.

    I like the idea of sterling engines and wonder if they could be used in conjunction with a steam turbine. Th
  • O&M Expense (Score:3, Informative)

    by sphealey ( 2855 ) on Wednesday January 02, 2008 @07:10PM (#21888336)
    Molten salt heat exchange technology isn't new, and has been tried in various forms of electric generating plant for at least 25 years to my memory (and probably a lot longer - they tried a lot of odd stuff in the 1920s and 1950s). The think to keep an eye on is projected operating and maintenance expenses over the long term. Molten salt is nasty stuff and does a lot of damage to everything it touches. Major components such as pumps have to be considered replacement rather than repair items for example. So the O&M cost projections are critical.

  • by MrKaos ( 858439 ) on Wednesday January 02, 2008 @07:13PM (#21888392) Journal
    I'm wondering if this is result of carbon taxes becoming inevitable. It would seem to me that some companies are positioning themselves to take advantage of funding and tax breaks that hopefully will become available in a carbon trading world. Even if the project can only address peak power demands it's certainly appears capable of offsetting a large amount of carbon production during peak energy demand times.

    If this is project is feasible and is what can be achieved without subsidies I wonder what solar energy projects (and indeed other alternative energy projects) can be created with funding.

  • by smellsofbikes ( 890263 ) on Wednesday January 02, 2008 @07:16PM (#21888428) Journal
    Here [legitreviews.com] is a shorter, and in my opinion, more informative summary. They're heating up sodium chloride salt, then using that to produce steam from water, which drives turbines. That's nice, because molten salt is fairly nasty stuff to work with.
    Anything has its chemical activity rise exponentially with temperature (the Arrhenius equation) so as things get hotter, they get more chemically aggressive. Molten glass will dissolve bricks and mortar. Molten sodium and chlorine ions are even nastier -- a sodium ion is a very small object [chemguide.co.uk], only a little larger than hydrogen -- and can diffuse into metals, weakening them and creating leaks.
    • Re: (Score:3, Interesting)

      by Dunbal ( 464142 )
      Here's an even shorter summary:

      "I've discovered perpetual motion^H^H^H^H^H free renewable energy, send me money".

      Come on. Use sunlight to melt salt to heat water? Why don't you just use sunlight to heat the water directly. Every step you add just increases your heat loss and decreases your efficiency, because no single step will ever be 100% efficient. There's nothing magical about salt, molten or not. And you can't beat thermodynamics. Ever.
      • Re: (Score:3, Informative)

        They're using the sodium chloride as a thermal reservoir -- heating it and relying on its high temperature to make up for its so-so specific heat. Water's specific heat isn't much different, but it's difficult to contain as steam. So they heat up the salt -- or anything else -- and let it gradually cool down, extracting heat from it by vaporizing water and reclaiming the energy through turbines. That way they can produce power all night off the heat saved during the day.
        It's not a bad idea if they have a
  • by Mr. Roadkill ( 731328 ) on Wednesday January 02, 2008 @07:46PM (#21888766)
    The future world will have to depend on a mix of energy sources, most renewable, some probably not.

    This kind of thing will work great for Las Vegas, and a number of Moroccan arrays would be great for Western Europe with submarine cables across the Mediterranean. Hell, there's lots of great possible sites for this kind of thing in Australia too - even more, if we look at things like using the peak to do things like pump salt water up hill, or store pressurised air, where a couple of days of cloud cover and peak demand won't result in solidification of your thermal reservoir.

    But what about Galena, Alaska? With places like that, the options are probably need to either continue shipping in hydrocarbons (either fossil or renewable)or ship in a micro nuclear plant.

    I know this is going to sound like some bizarro socialist mish-mash, but what just might be needed is a pricing structure for energy that's in part based on actual costs, in part based on environmental impact, and in part based on the practicalities involved in providing power in a particular location. Under such a scheme, Las Vegas might pay an absolute fortune for electricity generated from natural gas fuelled turbines (a.k.a. ex-airliner jet engines) but very little for solar - enough to make solar the far more attractive option, but allow the gas turbines to be kept available for peak demand (e.g. aircon load on the hottest days, because a couple of arrays are down for maintenance). Galena, however, would probably pay cost of production + shipping + reasonable profit margins for the biodiesel used to fuel its generators, plus maybe a very small surcharge for any mineral diesel purchased and cycled through as reserve stocks (due to biodiesel's shorter storage life). What this would involve is some proper resource planning, above and beyond just what's going to provide the biggest return to investors over the next three to five, and that's why I don't hold much hope for it happening. If we're smart as a species, though, we'll look carefully at how we can reduce our dependance on fossil fuels while still holding them in reserve for emergency power uses or using them for specialised purposes - feedstocks for manufacturing, for example, rather than as a general source of power.
  • by AbRASiON ( 589899 ) * on Thursday January 03, 2008 @05:50AM (#21892452) Journal
    What is it with intetnet sites (slashdot, news sites, digg etc) having fascinating articles but no cool pictures to back them up?

    Did anyone else groan intensely last year when 'worlds largest squid has been caught!' articles came up with no pictures?
    "Meteor smashes into datacentre"
    "Worlds largest seal clubs man in Alaska"
    "100ft tall hot woman with massive breasts seen naked crossing major highway"
    "Worlds coolest event happens! No pictures here!"

    Anyhow to get the rant over with,.........
    http://ucdcms.ucdavis.edu/solar2/photos/ [ucdavis.edu]

    That site is an existing site with one of these fascinating reactors, I found the site some time last year (and had a hell of a time finding the damn link in my history too) check it out purely for the cool factor, good stuff.

If you suspect a man, don't employ him.