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CA's First Molten Salt Energy Plant Approved
An anonymous reader writes "This year we've seen molten salt power plants start to pick up steam around the world, and now the technology is heating up stateside — California just approved its first molten salt energy plant. Designed by SolarReserve, the plant uses heliostats to focus thermal energy on a power tower filled with salt, which is able to reach very high temperatures (over 1000 degrees Fahrenheit) and can hold heat for an extraordinary length of time. Heat from this reserve of molten salt can then be pumped through a steam generator to provide on-demand energy long after the sun has set."
We get it already, heat jokes. Knock it off!
Another non-functioning site was "uncertainty.microsoft.com."
The purpose of that site was not known.
Any way to work this out for home use? Without digging too deep, sounds suitable here in So Cal, but maybe the scale is too small to provide any real benefit
http://en.wikipedia.org/wiki/Solar_power_plants_in_the_Mojave_Desert
Only if you ignore Solar II that ran from 1996 to 1999....
---In a time of Chimpanzees I was a Monkey.
Nothing from or controlled by Computer Associates should be trusted with warm water, much less molten salt.
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
Eliminate that make-believe accuracy, as the original was probably rounded at least +/-50 F to the round 1000 figure. 800 Kelvin is plenty accurate here.
Any excess salt left over after building the plant will be given to Gawker to help them improve their salted password hashes.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Slightly off-topic (or on-topic considering the bigger picture). Can this method of heat concentration be used in the refinement of silicon. My understanding is that silicon production is expensive because of the energy needed to generate heat for the process.
http://en.wikipedia.org/wiki/Silicon#Production
Does anyone know exactly how long the reservoir tanks will keep the molten salt at a high enough temp to be useful? It says it can run for 24 hours but should an abnormally long string of cloudy days occur would this inhibit its usefulness? I realize it's California so it should be fairly sunny year round but I'm not familiar with the area it's being built at. Looked up the salt as well. (Had a hard time thinking it would be sodium chloride...) It's a mixture of sodium and potassium nitrate. I was a bit worried as nitrates tend to be violently reactive/explosive but this would only be with reducing agents. (so it should be relatively fairly safe if there was a leak.) However when potassium nitrate is heated above 560C (as it would in this plant) it turns to potassium nitrite and gives off oxygen. I'm curious if this would be an issue or if the sodium nitrate or something else in the mixture inhibits this. I imagine the oxygen would either stick in the solar collector part as a gas bubble or just be dissolved in the molten salt mixture. Anyone know? (My expertise is more in biochemistry than inorganic/industrial chemistry)
Proof I am not just seeing cigars: http://inhabitat.com/wp-content/blogs.dir/1/files/2010/12/Rice-Solar-Project-CA-3.jpg
Wouldn't it be safer to have that molten salt at ground level?
Not if you wanted to get within 100 feet of the central collector during the day.
They didn't have the desert sun pouring onto a thousand large mirrors perfectly aligned on something for hours on end. Their test was more about the ability to align all of these mirrors without technology. These kind of things are dependent on energy going in vs energy going out. A thin sail surrounded by cool damp sea air only being shone upon from one side is going to have a lot less energy going in, and a lot more energy going out than a desert solar array.
Besides that it is also a "trivial geometry" case. If you assume the collector constant the more obtuse the angle of reflection requires a bigger mirror. If the receiver is low, you end up with an obtuse angle out of necessity. The higher it is, the easier to obtain that magic 90 degrees that minimises the mirror size and from there cost and everything else.
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
Yes, lord knows the solar energy people don't want to literally make a pillar of salt.
It would drive the Fundies nuts, that they could then equate solar energy with Sodom and Gomorrah.
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
Seems to me there are more than a few countries with a lot of desert land that are already energy exporters. Now they can just export their energy in something other than liquid form.
Meh, it's just a broken scouter, nothing to wake yourself over.
With the first link, the chain is forged.
I assume that with the target being higher off the ground, the mirrors can focus the sun on it when the sun is closer to the horizon, allowing for more hours of heating per day.
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"I can't complain, but sometimes still do..." Joe Walsh
From TFA: "SolarReserve is hoping to begin construction toward the end of 2011." Doesn't say when they plan to actually have it functioning. From their own press release on SolarReserve's website, they still have to get environmental approval from BLM and Wester Area Power Administration and "anticipates concluding financing arrangements by mid-2011 in order to begin full on-site construction in the third quarter of 2011."
What happens when a bird flies too near to the tower?
A republican will pretend to care about the environment long enough to sound like a complete asshole.
Next time the sun comes, up, the salt's all cooled down, right?
TFA says it’s capable of producing electricity 24 hours a day, so presumably it doesn’t cool all the way down overnight.
Distributed Denial of APK: It takes 15 seconds to reply to him anonymously, but wastes tons of his time if we all do it.
Yes, lord knows the solar energy people don't want to literally make a pillar of salt.
It would drive the Fundies nuts, that they could then equate solar energy with Sodom and Gomorrah.
Not only that but I prefer my utility bill as it is: measured in kwh not in Lot's Wives.
I'm beginning to suspect the Mythbusters intentionally blow it once in a while just to give the geeks something to argue about. That gets them more buzz.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
It takes several days and nights of little to no sunlight for the salt to cool down enough to no longer be molten and useful.
I read it and got prematurely excited because I thought someone finally had the balls to ignore the anti-nuclear-as-a-religion crowd, and started building a Molten Salt Reactor. Then I read the article and found out it's just a new take on boring old solar. Oh well.... one day...
640K ought to be enough for anybody
I didn't see anywhere in the article where they say that Sodium Chloride (i.e. table salt) was going to be used. I thought power plants typically used a different kind of salt (Sodium Nitrate?) to store thermal energy?
Since the diagram in the article shows the "cold" tank being at 550 degF, then they must not be using sodium chloride or it would be a solid in that tank.
In this case, more likely Sodium and Gomorrah
As I pointed out in my logs about 3 years ago, we should build molten salt generators, BUT use these for excess electricity storage. By building SMALL units (1-20 MW) these will take 1 acre or less to run. Then set up tax breaks to encourage small businesses of these. With that approach, it could buffer energy from AE, but also, it would allow grabbing the energy at night (cheaply) and then selling it during the day (for a profit).
I prefer the "u" in honour as it seems to be missing these days.
Going back to the original topic of how hot the salt is .. if you stuck one hand in molten salt that was 810.777 kelvin and the other hand in molten salt that was 800 kelvin could you tell the difference ?
To mere mortals 800 kelvin or 1000 Fahrenheit is perfectly acceptable :-)
Looks like saltpeter (sodium nitrate and potassium nitrate) with a bit of calcium nitrate mixed in is the currently preferred mix with a ~220C melting point.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.