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Molten Salt-Based Solar Power Plant
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?"
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.
"The fight for freedom has only just begun." - Geert Wilders
" 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.
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.
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.
Except that you can't easily get electricity from Morocco to Europe. Transmission of electricity isn't lossless or free.
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.
My ism, it's full of beliefs.
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.
Support a few technologists in Washington.
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?)
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.
Yep, I never spell check.
More incorrect spellings can be found he
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.
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.
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.
Can you be Even More Awesome?!
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.
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.
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
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.
An Education is the Font of All Liberty
To anyone who has ever smoked an unfiltered gauloises, the reason for this should be obvious.
'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.
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.
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.
What sound do people on rollercoasters make? Hint: it's not Xbox 360.
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.