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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?"
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Molten Salt-Based Solar Power Plant

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  • 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. :)
  • 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 oldenuf2knowbetter ( 124106 ) on Wednesday January 02, 2008 @07:05PM (#21888280)
    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 the atmosphere and,

    2) They never tell us the price of crude oil used for the cost justification.

    It is extremely unlikely that any such comparison will give oil quite so much of an advantage if computed at $100+ per barrel (today's price) for imported crude. Or at $200 per barrel. Or if imported crude isn't available at any price.

    Yes, I know that I ignored coal as a fuel. I live in California and every fuel-burning power plant around here runs on oil or natural gas depending on weather conditions. Coal isn't an option for pollution reasons. And we do have thousands of square miles of desert that are ideal for solar power plants.
  • by WaltBusterkeys ( 1156557 ) on Wednesday January 02, 2008 @07:12PM (#21888364)
    Don't forget transmission costs--even if Morocco produced enough power for western Europe, the power would still be in Africa instead of Europe. Long-distance power lines are expensive, vulnerable to failure, and lose (at best) 10% of power transmitted. There's water between Europe and Africa, meaning that they'd either have to string really big lines across Gibralter or run a giant copper cable. Going underground through cable is expensive and leads to larger power losses because you can't run the same high voltages in the middle of a salt bath as you can from high-tension wires.

    All of that assumes that having a single point of failure for all power in western Europe would be a good idea. Seems like it would make a lucrative target for political disruptions, a massive piece of negotiating leverage for Morocco, and vulnerable to all kinds of natural disasters.

    And don't get me started on microwave power transmission. Haven't we all played enough SimCity to know how that can go horribly wrong?

    If it really were that easy then greed would have caused Bronson (or somebody else) to have done it already. He's incredibly greedy but usually tells established business to go bugger itself and launches disruptive technologies when there's an opportunity to undercut the market.
  • 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.
  • 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 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 Anonymous Coward on Wednesday January 02, 2008 @07:20PM (#21888468)
    Gasoline? Wowee!
    Let's do the math, folks.

    Presuming you want to use gasoline, first you are going to have to FIND some crude oil. This is difficult and expensive because most crude oil is hiding deep underground. Then you are going to have to dig a well to bring it up. You will have to pump it, store it and move it to where it is needed. You are going to have to move A LOT of it, so you will need some real super tankers (each one will cost hundreds of millions of dollars just to build) You will have to "refine" the oil into gasoline, and then transport THAT. Every step along the way will not only cost money, but will consume some of the crude oil you dug up. It seems unlikely that there will be anything left to trickle out the pipe at the end.

    I suspect you'll have trouble getting the cost down to an economical level. By about a factor of thirty. Even assuming economies of scale. Good luck selling your idea to the bankers.

    (isn't made up math fun?)
  • by bluelip ( 123578 ) on Wednesday January 02, 2008 @07:21PM (#21888478) Homepage Journal
    The guy above me may be correct.

    Specific heat capacity and the ability to move the energy store are more important than the rate at which the material conducts thermal energy.

  • 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 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 Anonymous Coward on Wednesday January 02, 2008 @07:44PM (#21888740)
    when the sun is out, and Wind is great when the Wind is blowing, but they are not viable for providing base load power [] needs.

    Nuclear is ideal for providing base-load power (30-40% of peak capacity), suplemented by Solar, Wind and Tidal power.
  • Not that new... (Score:5, Insightful)

    by zippthorne ( 748122 ) on Wednesday January 02, 2008 @08:15PM (#21889032) Journal
    This kind of thing has been suggested for use in high-power spacecraft, and it's not necessarily sodium salt that's the storage mechanism.

    I don't see why you'd lose much efficiency. You'd chose a salt that was molten over the operating range, and no matter what, you cannot exceed the temperature limitations of the other materials you've built the thing from, so that's your design temp. Because of the T(t) smoothing effects, you'd be able to run the generator at maximum efficiency for most of the time. Thus, you can size your machinery to the average capacity rather than the peak available solar input. Not spooling the generator up and down as the sun waxes and wanes is great for efficiency.

    For instance, you might pick a salt that has a liquid-solid transition just below your desired T_hot, ensuring even temperature until all the salt solidifies. This has the added benefit that, depending on the expansion characteristics of the salt in question, you have a number of ways to evaluate the remaining generating capacity.

    With good insulation, and a fixed installation can be made arbitrarily well insulated, you would lose a lot less energy than storage in batteries, and it scales very well: the larger the installation, the thinner the needed insulation is relative to the total volume.

    The main loss would be radiation from the absorption patch. Presumably you'd mitigate this by having some kind of louver or hatch that you could close to insulate that during the night and overcast days. You could also take advantage of the much lower-than-the-sun temperatures, and use a covering that is transparent to visible light, but reflective to lower frequency light. Although there would still be a fair bit of radiation in the visible at reasonably efficient temperatures.

  • by dbIII ( 701233 ) on Wednesday January 02, 2008 @08:21PM (#21889102)
    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 the newer and UNTESTED concepts it would be more than using a bomb materials plant to boil water which is what most of our 1950's derived plants really come down to.

    There are a lot of good uses for nuclear materials but we are not yet very good at using them to boil water, and the "nuclear batteries" while they rule their niche scale up no better than photovoltaics.

  • 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 []. (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.

  • by dbIII ( 701233 ) on Wednesday January 02, 2008 @08:39PM (#21889268)
    Uranium is not rare at all. Turning the stuff into fuel is hard and requires the heavier isotope - so you need a lot of high quality ore to get fuel in an expensive and energy intensive process (eg. heat a heavy metal all the way to a gas and centrifuge it). Now if the ore contains a lot of uranium, copper and gold (as some does) it is well and truly worth it but you get diminishing returns with other ore until eventually you reach a point where it is not worth it. That is why there is talk about running out of quality uranium if there was a sudden move to build a lot of plants of current design. That is one of the reasons why there has been work on Thorium for decades - it's not as difficult to get the fuel as uranium, and why there has been work on less energy intensive techniques to make the fuel than gas centrifuges. When the end product is energy you want to use as little energy as you can get away with to make the fuel.

    Reprocessing was mentioned - it doesn't happen outside of experiments now because it is not easy. With high grade waste everything has to be done by remote control, doesn't sound like a big deal but it was ultimately the problem that killed the Superphoenix project and is why we don't have reprocessing or producation scale fast breeders.

    Clean was mentioned - good in advertisements for washing powder but an irrelevent advertising lie for any industrial process.

    As for the cheap power in France I cannot get the numbers due to the nuclear electicity generation being part of a defence program so it is SECRET - how did you get that information or are you guessing? Remember that these are dual use plants that make and sell weapons materials which offsets the costs a bit but it fairly irrelevant in the context of civilian nuclear power.

  • by Anonymous Coward on Wednesday January 02, 2008 @08:57PM (#21889458)
    Solar2 (similar concept) generated 19.6M KWH/year in 128 acres of land. It thus produced 37 kwh/m2/year. You'd need 24M acres of land to meet the electrical needs of the US using Solar2. That's 22% of california.

    Care to guess how many square miles of mirrors that would be? If each mirror frame was 10 pounds of aluminum, it'd take several years of world aluminum production just to make the mirror frame.

    The problem with all this alt energy stuff is that very few grasp just how large the numbers need to be to make this work. They see things like "This guy in Iowa has a windmill he built for $119 and it generates 100,000,000 mW when the wind is blowing and runs much of his house". And folks see enough zeros and figure "Holy crap, why isn't this being done for everyone? Must be a conspiracy!"

    If you want nearly-zero carbon, then nothing comes close to delivering the scale needed, except for nuclear.

    Wind? Hah. The mast on a giant turbine that is 250 feet tall is around 90 tons. Just for the mast. And we need about 1.6M of those things. That's a lot of steel. That's about 2700 hundred skyscrapers worth of steel. And care to guess how much concrete you need? It requires more concrete to hold 1.6M wind turbines in the ground that it does to build the few hundred reactors we'd need to power the US.

    In short, do the math. Whenever you see a claim for alt energy, remember the US needs about 3.6T KWH of energy each year. Take the "nameplate" rating of the technology, divide that by 10, and then convert it into KWH. You'll be amazed how ineffective most of this is.

    For reference:

    0.16% of California needs to be covered in nuke plants to power the US

    1.13% of Cali needs to be covered in wind turbines to power the US (assuming there are enough windy areas)

    2.6% of Cali needs to be covered in solar cells to power the US (assuming there are enough sunny areas)

    22% of Cali needs to be covered in Solar2 plants to power the US (again, assuming there are enough sunny areas)

    2000% of Cali needs to be covered in biomass (switchgrass) to power the US

  • by yariv ( 1107831 ) <> on Wednesday January 02, 2008 @08:59PM (#21889490)
    Canada and Australia currently supply more then 50% of the uranium in the world. Australia also holds about 40% of the known reserves. I think I can live with them as "the new Saudi Arabia of energy".

    However, in the long run, we'll have to use other sources of energy. Solar and fusion, simply because we'll probably run out of cheap uranium before the 23rd century. (unless we'll be able to extract the uranium from the seas, then we'll probably have enough for several thousand years).
  • 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 [] in mines underground that are adding anything from 1-5% of the worlds Co2.
  • by MrKaos ( 858439 ) on Wednesday January 02, 2008 @10:05PM (#21890046) Journal

    Nuclear is ideal for providing base-load power (30-40% of peak capacity), suplemented by Solar, Wind and Tidal power.
    Geothermal is ideal for providing base-load power (30-40% of peak capacity), suplemented by Solar, Wind and Tidal power.

    Fixed that for ya, Mr AC.

  • by gambolt ( 1146363 ) on Wednesday January 02, 2008 @10:34PM (#21890246)
    To anyone who has ever smoked an unfiltered gauloises, the reason for this should be obvious.
  • by TooMuchToDo ( 882796 ) on Thursday January 03, 2008 @01:08AM (#21891244)
    'Twas an excellent article, although I disagree with some of their points. While we should be building out renewable infrastructure as quickly as possible, we shouldn't put all of our eggs in one basket with solar. Also, they don't take base load into account. Yes, we're working on methods to store the solar energy during the night through molten salt, but if it's not quite there yet, we shouldn't base a plan on it that needs to work at all costs.
  • by Mark_MF-WN ( 678030 ) on Thursday January 03, 2008 @04:12AM (#21892068)
    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 amounts of fuel. And once we finally get past this kind of pathetic cowardice, we can finally start putting serious investment into research into nuclear power -- and get ideas like the Thorium and Actinium fuel cycles into practice, allowing nearly perfect reprocessing and allowing the exploitation of Thorium, which is incredibly abundant. And uranium isn't exactly rare -- it's just uranium 235 that's rare, and we don't even need to use enriched uranium in many reactor designs.

    Seriously, what's wrong with you people? No one questions the value of solar, but it's not a panacea. We need more than one energy source. It's that kind of ridiculous thinking that got us into this situation where we're overly dependent on fossil fuels. We should have been diversifying our sources of energy all along, not wimpering in the corner because of paranoid delusions about t3h rad1at10n coming to get us.

  • 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 dbIII ( 701233 ) on Thursday January 03, 2008 @08:05AM (#21892900)
    As an engineer with a background in power generation (but ten years out of touch and most of the nuclear power plant guys I worked with were Russian and Indonesian) I'd say what we'll be using in the future as in the past is a mix of a lot of things depending on what is easiest in specific locations. There are solar thermal baseload designs that usually run on the principle of having a big heat reservoir (in this case molten metal salts) to run stuff around the clock but they all have to be large so there is resistance to building them. Your average thermal plant can run for quite a while after you stop shoving in fuel because there is so much steam in the system so this is expanding on the idea (ie. being able to give you a full nights worth of steam after the power is cut). What most people miss is that the real problem in electicity generation is covering the peaks - and they almost always happen in daylight anyway.

    This is going to take years and it's a matter of people seeing a lot of solar hot water collecters on rooftops before governments decide it is a safe bet to go for large solar power projects - I think industry on it's own will hit exactly the same problem the nuclear power advocates have. For really big thermal plants they want government money because they can't get commerical finance. Electricity is heavily regulated in most places anyway so it usually takes government involvment to just get a foot in the door. This sometimes involves convincing relatively old people who did not have the benefit of finishing high school of the merits of a project - hence the delay until solar thermal (eg. hot water) comes into the personal experience of the people regulating things.

"If you lived today as if it were your last, you'd buy up a box of rockets and fire them all off, wouldn't you?" -- Garrison Keillor