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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 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 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,


  • 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 [] 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 cybrthng ( 22291 ) on Wednesday January 02, 2008 @07:14PM (#21888406) Journal
    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 Anonymous Coward on Wednesday January 02, 2008 @07:15PM (#21888416)
    According to Wikipedia, Morocco has a land mass of 446,550 km^2. 3% of that is 13,396 km^2. That's approximately the size of Montenegro (13,812 km^2). It's more than five times as big as Luxembourg. Of course, if you point out that you'll have to dedicate five Luxembourgs to power generation, it becomes much less appealing.

    According to [] , Europe has 803 gigawatts of installed generation capacity.

    Going to [], and picking 5 reactors at random (Brunswick, Diablo Canyon*, Pilgrim, Surry, and Susquehanna), I see that 7.5 GW of generating capacity takes up 5,465 acres... or 22 square kilometers.

    So, the land usage to supply all of Europe's electric usage (day and night) via nuclear power would be 2,354 km^2... potentially less, as it seems that it's possible to group reactors together to minimize land usage. That's less than one Luxembourg.

    * Chosen less randomly than the others, since it had a cool-sounding name.
  • by jonwil ( 467024 ) on Wednesday January 02, 2008 @07:22PM (#21888490)
    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.
  • by darklordyoda ( 899383 ) on Wednesday January 02, 2008 @07:26PM (#21888532)
    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. In other words, the molten salt requires a larger initial investment, but upkeep is lower. This solar system they are talking about seems like a variant of these molten reactors, only replacing the core with a solar concentrator/collector.
  • by Dunbal ( 464142 ) on Wednesday January 02, 2008 @07:40PM (#21888692)
    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.
  • 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 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 greg_barton ( 5551 ) * <> on Wednesday January 02, 2008 @07:55PM (#21888868) Homepage Journal

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

    Back in 1960 my grandfather patented [] a fuel creation process for molten salt reactors while working at ORNL. These days my uncle is carrying the torch [] 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 technology is all there, so when the environmental and peak oil shit really starts hitting the fan nuclear power will be up to the task. It'd be nice if we could be ahead of the game a bit more, but that's OK. The solution is there. We just need to be sufficiently motivated to do it.
  • by Rei ( 128717 ) on Wednesday January 02, 2008 @08:40PM (#21889288) Homepage
    Range and charge time are both insufficient, and are likely to remain so for the foreseeable future.

    Huh? Fast charge li-ion batteries will be out in the next few years -- several companies (including big players like Toshiba) have already announced them. We're talking 5-10 minutes for a full charge. As for range, didn't you see the Stanford study headed by Yi Cui that got 10x the lithium ion density in the anode with silicon nanowires? The team estimates it'll take about 5 years to commercialize that with conventional cathodes, giving "several times" better energy density than current li-ion. Most research has been on the anode; there's tons of room for improvement in the cathode, so that likely means the potential for improvement to a full 10x energy density. Even with just 3x, that'd mean in 6 years or so, we'll have electric vehicles meeting or exceeding the performance of gasoline vehicles in both respects.

    Arrays of nuclear power plants could be constructed for the express purpose of electrolyzing water and creating hydrogen, which could then be shipped around and sold at stations as fuel currently is. With an energy density of 143MJ/kg, hydrogen compares very favorably to gasoline, which only stores 46.9MJ/kg.

    Hydrogen has horrible energy density, and the system efficiency of hydrogen vehicles is pathetic incomparison to electrics. Improve the density with a storage medium and you make the efficiency even worse. And let's not even talk about safety.

    Advances in li-ion technology have essentially rendered hydrogen obsolete before it even got a real chance.
  • Re:sun renewable? (Score:2, Interesting)

    by JoshHeitzman ( 1122379 ) on Wednesday January 02, 2008 @11:23PM (#21890598) Homepage
    No she was not right. A renewable resource is one that we humans can currently cause to be renewed through our own actions. For example when we harvest plants we can plant new ones in their place. Wind, hydro, and solar power all come from the sun. Tidal power comes from the moon and a lesser extent the sun. Geo-thermal comes from the earth. We humans do not currently have the ability replace the sun or increase its life span. We also do not have the ability to prevent the earth and moon from becoming tide locked. Nor do we have the ability keep the Earth from eventually growing cold. Some day we may have that ability, but it seems likely that we will have developed fusion in order to supply the energy needed to implement those capabilities in which case we won't need energy from those sources any longer and we'll be pulling the matter we need to fuel the fusion reactors from the ocean and then quite probably gas giants. It's also interesting to note that we do have the capability of creating coal from wood (i.e. charcoal) so we could replace the coal we consume, there just isn't much of a point in doing so for most electricity generation as it would be better burn the wood directly (or use the same land to produce crop that yield more useable BTUs per acre). Similarly we can create crude oil from organic matter using thermal depolymerization. Never looked into the generation of natural gas or propane, so I'm not sure if that's feasible at the moment.
  • by falconwolf ( 725481 ) <falconsoaring_2000@yah o o . c om> 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" []. However another /.er brought up the Candu [] 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 [] 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 []. Combining wind, solar power, cogeneration or waste heat recovery [] 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 [] in New York can provide electricity to NYC. The farmer would then have a second source of income.

  • by Arthur Grumbine ( 1086397 ) on Thursday January 03, 2008 @01:00AM (#21891200) Journal
    Although your exaggerations do allow for a much more pronounced emotional impact on the reader, if you were interested in perspective (i.e. proper science) here's what your source's source has to say []:

    1. Coal fires are a natural occurrence albeit aggravated, and sometimes caused, by human mining.

    2. In China, which has the by-far greatest collection of coal fires, "estimated" 20 - 200 million tons of coal burn every year in coal fires. That is an incredible range... 20 to 200...mmm... that's some good science. Assuming 200 million tons of coal, and all of it man-caused, you get "nearly" 1 whole percent of the carbon dioxide emissions "due to fossil fuels being burned".

    As a side-note, "the world's Co2" [] weighs in at about 3x10^15 kg, or 3x10^12 tonnes, or 3,000,000 million tonnes, or 3,000 billion tonnes. All of human activity (fossil fuel burning and everything else) produces 27 billion tonnes of CO2 each year. That's right. ALL human activity contributes less than 1% to "the world's Co2" each year.

    Please do not let Wikipedia think for you. The FSM did not bestow brains (the very image of His Compacted Noodlieness) upon us so that we might neglect our duties to rigorous science (or in this case, simple math).
  • by TooMuchToDo ( 882796 ) on Thursday January 03, 2008 @03:34AM (#21891888)
    Yes, I read the whole article (about 2 days ago, as I subscribe to SciAm). A recent Nature article has already noted that we've most likely hit a tipping point of CO2 parts per million in the atmosphere. Using natural gas is unacceptable, as any plan going forward has to eliminate CO2 emissions, not just reduce them. A more prudent solution would be for wind and solar to shave peak loads during the day, as well as charge electric vehicles, while nuclear and hydro would be base load for night power usage. I can't stress this enough though. CO2 emissions have to be eliminated due to how much we've already dumped into the atmosphere. Sounds crazy? Check back with me in 3-5 years when carbon sinks such as the ocean and rain forests refuse to absorb more CO2 because they've become saturated, and global warming accelerates.
  • by ibbey ( 27873 ) on Thursday January 03, 2008 @05:01AM (#21892282) Homepage
    Thanks for your input. Some quick googling suggests that the current state-of-the-art hydrogen conversion is approaching 75% efficiency (See [], note this is lab efficiency, not truly applied yet). Assuming that the efficiency continues to improve, I would expect that that value will rise notably by 2020 and beyond. When you factor in the NG used, transmission losses, etc., compressed air is only about 80% efficient (see post 101 [] of the SciAm discussion), so it would seem that hydrogen might be feasible as a replacement in the not terribly distant future.

    Since there would also be lost efficiency going the other way (hydrogen > electricity), it probably isn't a very good sole storage solution, but it would seem to be a good solution to burn hydrogen in place of the NG. That would obviously result in further reduced efficiency, but would remove any Co2 from the equation. I'm not a chemist, physicist, or really any other -ist, but it seems like there is at least some potential there.

We can found no scientific discipline, nor a healthy profession on the technical mistakes of the Department of Defense and IBM. -- Edsger Dijkstra