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World's First Molten-Salt Solar Plant Opens

timothy posted more than 4 years ago | from the entire-mountain-is-covered-with-snow dept.

Power 316

An anonymous reader writes "Sicily has just announced the opening of the world's first concentrated solar power (CSP) facility that uses molten salt as a heat collection medium. Since molten salt is able to reach very high temperatures (over 1000 degrees Fahrenheit) and can hold more heat than the synthetic oil used in other CSP plants, the plant is able to continue to produce electricity long after the sun has gone down. The Archimede plant has a capacity of 5 megawatts with a field of 30,000 square meters of mirrors and more than 3 miles of heat collecting piping for the molten salt. The cost for this initial plant was around 60 million Euros."

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Already done? (1, Insightful)

Anonymous Coward | more than 4 years ago | (#33000040)

Um what? I swear I saw a documentary about a US plant which did the same thing (even looks the same) and that was years ago.

Re:Already done? (4, Informative)

Xandar01 (612884) | more than 4 years ago | (#33000102)

This one doesn't use salt, but we have had one very similar built here back in 2008. http://www.renewableenergyworld.com/rea/news/article/2010/07/areva-boosts-solar-supersteam-parameters-in-bakersfield [renewableenergyworld.com]

Re:Already done? (0)

Anonymous Coward | more than 4 years ago | (#33000230)

Parent here, I think Bakersfield was the one I was referring to but I thought they said they switched molten salt because I remember them talking about having to ensure they maintain the temperature of the salt so it didn't harden and clog the pipes.

Re:Already done? (2, Interesting)

Benaiah (851593) | more than 4 years ago | (#33000274)

5MW? Its sad that one HV pump on a process plant will use all of this. Miners should really have to purchase some of their power from renewable energy. It will stop them(us) from blatantly wasting power because its cheap.

Re:Already done? (1)

Anonymous Coward | more than 4 years ago | (#33000450)

Why is that sad? How much energy should such a pump use be using so that none is wasted?

Re:Already done? (3, Interesting)

TapeCutter (624760) | more than 4 years ago | (#33000608)

A 5MW windmill can be up and running for about 1.5M euros, but a pilot plant such as the one in TFA does not have the same goals as a commercial plant.

Re:Already done? (0)

Anonymous Coward | more than 4 years ago | (#33000166)

I'm with this guy. Reading Rainbow or 3-2-1 Contact or Mr. Wizard or something like that did a significant piece on Solar One near Barstow, CA which covered the molten salt technology.

Re:Already done? (4, Informative)

Forge (2456) | more than 4 years ago | (#33000672)

Do you mean the one mentioned in the middle of this article [earthlink.net]

"Molten salts have been used in many industries as a high temperature heat transfer medium. The 'highest profile' use of molten salts in this regard is the Solar Power Tower near Dagget, California (excuse the pun). It uses a Sodium Nitrite/Nitrate mixture to absorb and store the sun's heat from the focus of many mirrors in the desert upon a central tower. The heat from the salt is then transfered via a heat exchanger to produce steam to drive a conventional steam turbine and generator to produce electricity from the sun for Southern California.3a"

"Last modified, 20 Nov 97"

Molten Salt. (0)

Anonymous Coward | more than 4 years ago | (#33000042)

That's pretty bad ass.
Know what's awesome? There's more than enough energy for everyone, even after fossil fuels become prohibitively expensive.
Take that, nature! Lots more of us on the way!

Table manners (0)

Anonymous Coward | more than 4 years ago | (#33000044)

Honey, could you please pass the molten salt?

Sounds cool, but... (3, Insightful)

Anonymous Coward | more than 4 years ago | (#33000054)

Ok, so it can produce after the sun has gone down, but wouldn't the inverse be true, too, i.e. it'll take longer for it to reach a heat at which it can start producing in the morning? Anyone who didn't fail physics want to help an ignorant AC out?

Re:Sounds cool, but... (0)

Anonymous Coward | more than 4 years ago | (#33000068)

Sounds about right.

I would compare this to the temperature buffering effect of a lake, or the steadying effect of an engine's flywheel.

But if molten salt can hold more heat than some alternative, that alone is a good reason to use it.

Re:Sounds cool, but... (1)

Narcocide (102829) | more than 4 years ago | (#33000108)

I would presume it works by making use of some amount of waste energy the solar panels themselves cannot fully absorb during the day.

Re:Sounds cool, but... (4, Insightful)

jamesh (87723) | more than 4 years ago | (#33000134)

I don't think you'd have to heat up all of your thermal mass to start producing energy. If you only need a certain fraction of the thermal mass to produce the amount of energy you need then the rest can be a 'battery' that you charge up during the day when there is extra solar radiation going into your system.

Re:Sounds cool, but... (4, Insightful)

Deflatamouse! (132424) | more than 4 years ago | (#33000426)

In other words, there's value in the ability to produce energy at a constant rate, rather than in bursts. Because when it's produced in bursts, you will have to find a way to store it, which means a loss in efficiency.

Re:Sounds cool, but... (4, Interesting)

arivanov (12034) | more than 4 years ago | (#33000214)

The network peak is in the first hours in the evening. Morning (while it warms up) is relatively low consumption. So if it can work through to what in the UK is referred to as the "Eastenders hour" it is well worth it. Pity they built it in Cicily though, I would really like to see those built in quantity in the Sahara. More sun, hotter sun and less cloud. The distance across the mediteranean is well within the limits of modern tech for a high voltage line on the sea bed. High voltage is also considerably safer compared to gas or oil in an earthquake zone (which is pretty much all of the Med).

Re:Sounds cool, but... (4, Insightful)

T Murphy (1054674) | more than 4 years ago | (#33000266)

The Sahara may be a good place for mass production of solar power, but for a first-of-its-kind plant, keeping it close to home is a safer move (assuming the firsts involved don't put the neighbors at risk), in addition to needing to prove it is worth scaling up as opposed to other designs. This plant isn't wildly different, but given the cost of power plants and the demand for power, reliable and proven technology is a must before going beyond small-scale.

Re:Sounds cool, but... (3, Informative)

TapeCutter (624760) | more than 4 years ago | (#33000536)

N. Africa seems to be high on the list of places where the EU want to go with solar [guardian.co.uk] .

Re:Sounds cool, but... (4, Informative)

Basje (26968) | more than 4 years ago | (#33000564)

The location of the plant in Priolo Gargallo is not that far from the Sahara. It's actually a little more south than the northernmost part of the Sahara in Tunesia, which is roughly 250 miles west of the plant. The solar radiation will be roughly equivalent, no need for undersea cables. Most importantly Sicily is a (slightly) more stable region that does not rely on income from oil like many of the North Sahara states.

Re:Sounds cool, but... (0)

Anonymous Coward | more than 4 years ago | (#33000320)

If they allow the salt to solidify, it would probably take la little longer to ramp up in the morning, but so long as they maintain a liquid state, it would work as well as any of the oils currently employed. Also, I believe one of the goals of this endeavour was to use a more benign material as the energy conduit. Additionally, salt has a greater capacity to absorb energy than the oils currently used, so I *think* that it has the ability to generate more gross energy over similar dimensions.

Oh no, it doesn't ... (0)

Anonymous Coward | more than 4 years ago | (#33000494)

Sounds rather hot, that's what it does!

What is the rating? (1)

Anonymous Coward | more than 4 years ago | (#33000060)

I see articles and news sites reporting its rated capacity at 5 MW. Is that thermal or electric? Most power plants write 'MWe' or 'MWth' to avoid this type of confusion. If it is only 5 MW thermal, then they are being really shady about this.

Back of the envelope power cost calculation (4, Interesting)

billstewart (78916) | more than 4 years ago | (#33000152)

Most articles talking about power generation are talking about electrical power, so I'd guess that.

Is this thing really cost-effective? If it's mostly a proof of concept it doesn't have to be, of course. I did a back-of-the-envelope calculation:

  • 5MW * 10 Hours/day = 50 MWH/day = 50000 kWH/day (assumes you don't get peak power all day.)
  • 50,000 kWH/day @ 10c/kwh = $5000/day (US power prices seem to start around 10 cents per kWH, though they're higher at prime times.)
  • $5000/day * 300 days/year = $1.5M/year
  • Euro 60M is about 50 years payback at that rate. Or 25 years if it's 20c/kWH.

So it's shiny and renewable (assuming the plant lasts a long time and doesn't break down into rusty mirrors encrusted with stray salt leaks in a year or two), and not *way* out of line compared to other power sources like coal plants, but it's not aggressively cheap either.

Re:Back of the envelope power cost calculation (3, Insightful)

c0lo (1497653) | more than 4 years ago | (#33000206)

Euro 60M is about 50 years payback at that rate. Or 25 years if it's 20c/kWH.

As the plant buffers the energy to use it at night, I'd be inclined to use a 24 hours/day * 5 MW.
Assuming that all the other calculations are correct, this would mean approx 21 years for the payback at 10c/kWh, or 10.5 years at 20c/kWh.

Re:Back of the envelope power cost calculation (1, Informative)

Anonymous Coward | more than 4 years ago | (#33000236)

Interest at 4%
2.4M a year
loss per year .9M

I wonder what it costs to operate ?

I would love to find out how much liability insurance is on molten salt.

Property tax might be cheap in Spain, or the tax bill on a couple hundred acres and a 60M plant would eat into that 5M subsidy they got.

Re:Back of the envelope power cost calculation (1, Insightful)

Anonymous Coward | more than 4 years ago | (#33000668)

This is the FIRST plant, what it cost is pretty meaningless. You need to ask what it would cost to deploy and run the next 1000 plants. Experience will accumulate, production will be scaled up and competition emerge.

Re:What is the rating? (2, Interesting)

Anonymous Coward | more than 4 years ago | (#33000186)

These numbers really don't add up. The article cites 2,100 tonnes of oil equivalent (which works out to about 3 MWth) and another cites 10 million kw-hrs of electricity per year (which works out to about 1.1 MWe). This would seem to imply the plant is about 3 MW thermal on average (and perhaps the extra 2 are only counted during the day). 30,000 square meters of reflectors perfectly aligned would generate about 30 MW thermal maximum at the best time of the year. Counting for night, seasons, etc., perhaps it could be diluted to 3 MWth.

Why are they citing all of the different numbers in CO2 equivalent, oil equivalent, and equivalent kw-hrs instead of actually saying what the actual electrical output is going to be on average?

Ooooooh. (3, Funny)

jtownatpunk.net (245670) | more than 4 years ago | (#33000062)

I thought the headline said morton-salt.

Re:Ooooooh. (2, Funny)

Born2bwire (977760) | more than 4 years ago | (#33000232)

When it rains, it p.... OH GOD! It's melting through my skin!!!!!

Liquid Fluoride Thorium Reactors (3, Interesting)

RudyHartmann (1032120) | more than 4 years ago | (#33000064)

LFTR's will render these things irrelevant. http://energyfromthorium.com/lftradsrisks.html [energyfromthorium.com]

You're forgetting something (4, Funny)

LordLucless (582312) | more than 4 years ago | (#33000144)

Ahhh! Nuclear! Ahhh! It'll explode and kill us all and poison the planet for a bejillion years!

Re:Liquid Fluoride Thorium Reactors (-1, Offtopic)

sunspot42 (455706) | more than 4 years ago | (#33000158)

I bet the power those things generate will be too cheap to meter, right?

Re:Liquid Fluoride Thorium Reactors (1, Insightful)

Anonymous Coward | more than 4 years ago | (#33000216)

A phrase one guy said back in the 50's, used often by anti-nuclear types, which needs to be retired.

Re:Liquid Fluoride Thorium Reactors (3, Insightful)

Sabriel (134364) | more than 4 years ago | (#33000308)

I wish it would hurry up and come true instead.

I truly hope you're right (1)

Scareduck (177470) | more than 4 years ago | (#33000162)

Solar's energy density is terrible, it doesn't store readily, and doesn't work when the sun goes down. Yeah, yeah, yeah, that's what the molten salt is for, but tell me this: how long can you afford to be without actual sun (number of consecutive cloudy or mostly cloudy days) before this is neutered? Thorium fission is the most likely way out of the current energy conundrum. If its proponents aren't lying to us or themselves about its economic viability.

Re:Liquid Fluoride Thorium Reactors (4, Insightful)

phantomfive (622387) | more than 4 years ago | (#33000512)

Yeah, and fusion will one day render liquid fluoride thorium reactors irrelevant, but they've built something now, and it's environmentally friendly, and as long as the cost is reasonable, who cares? They still have something good now.

Re:Liquid Fluoride Thorium Reactors (3, Informative)

interkin3tic (1469267) | more than 4 years ago | (#33000554)

LFTR's will render these things irrelevant.

I try not to anticipate future technology that seems right around the corner, because otherwise I'll just get depressed thinking about where I am now: in an apartment, most appliances in which are not connected to the internet to manage themselves as I fly to Hawaii in my flying car, playing Duke Nukem Forever on my VR headset.

And no that wouldn't be unsafe because cars today are supposed to be driving themselves, I'm assuming that would work for flying cars too.

Anyway, if molten salt solar plats really do become obsolete because of whatever not-here-yet power source you're talking about, we'll have a good mass-popcorn maker.

Solution To Your Problem (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#33000066)

Fuck me raw. SERIOUSLY! Will someone FUCK ME RAW?

Re:Solution To Your Problem (0)

Anonymous Coward | more than 4 years ago | (#33000174)

Thanks for the offer, but we don't like fucking disease-riddled manwhores around here...

Should improve efficency! (5, Informative)

Antony T Curtis (89990) | more than 4 years ago | (#33000074)

This is big news!

The larger the temperature difference, the more efficiently we can turn the heat into electricity. Superheated steam is just too difficult to manage over distances so this would make a great first step of collecting the solar energy and transporting it to a single location to make superheated steam.

The best part is that NaCl is non-toxic and doesn't need to be kept under pressure. If you have a natural gas Bunsen burner and good test tubes handy, it is just about possible to melt salt and prove to yourself how stable it is. Just be careful about spilling it because it is hot enough to get things like wood and paper to auto-ignite on contact. The hottest temperature you can expect to achieve with natural gas is around 700 degrees Celsius, if I remember correctly.

(as a side note, this is why low pressure nuclear power plants have such poor efficiency - because the water is only at 100 degrees Celsius after being heated by the nuclear fuel).

"Salt" != "NaCl" (5, Informative)

billstewart (78916) | more than 4 years ago | (#33000112)

The article isn't specific about *what* salts they're using, but says "molten salts solidify at around 425 degrees F" - NaCl's melting point is about 800 C.
One of the articles they reference refers to another project that uses a mixture of sodium and potassium nitrates.

Re:"Salt" != "NaCl" (4, Informative)

c0lo (1497653) | more than 4 years ago | (#33000246)

The article isn't specific about *what* salts they're using,

This one [sicilyguide.com] does: the same as Solar One/Two - a mix of sodium/potassium nitrate.

Re:Should improve efficency! (0)

Anonymous Coward | more than 4 years ago | (#33000116)

I think nuclear power plant operators know something you don't.

Re:Should improve efficency! (0)

Joce640k (829181) | more than 4 years ago | (#33000196)

30 square kilometers of land for 5 megawatts output? To me that doesn't seem very viable...there's single wind turbines with more output than that.

Re:Should improve efficency! (4, Informative)

Anonymous Coward | more than 4 years ago | (#33000318)

30000 sq. m = 0.03 sq. km

Re:Should improve efficency! (4, Informative)

c0lo (1497653) | more than 4 years ago | (#33000336)

30 square kilometers of land for 5 megawatts output? To me that doesn't seem very viable...there's single wind turbines with more output than that.

30000 sqm does not make 30 sq km. Let's try some computations of achieved efficiency:

  • Input - going maximal here. Solar energy flux - 1.44 kW/sqm (ignore absorption in atmosphere). Thus total input= 43.2 MW. Say it for 10 hours/day = 432 MWh
  • output - 5 MW for 24 hours=120 MWh

Minimal modelled efficiency: 27%. - I'd say definitely a decent efficiency.

Can they improve? Keeping into account the last step of energy transformation (thermal->electric) operates between say 825 K (molten salt) and 400 K (water at 120 C - moving the turbines) and assuming a perfect Carnot cycle, the maximum efficiency achievable would be lower than 52%.

Re:Should improve efficency! (1)

Biogenesis (670772) | more than 4 years ago | (#33000348)

With the numbers in the article I calculated 167W/m^2, or about 6% given the nominal 1000W/m^2 of incident solar radiation. I'm not sure if that's 24 hour output though, depending on how much night time output those numbers include the efficiency could be almost double. This is an overall system efficiency too, so I'm going to put this project into the "pretty reasonable" catagory. This form of low carbon electricity generation has the big advantage of producing much more consistant output, which is great for allowing controlled smoothing out of wind output.

Re:Should improve efficency! (1)

vivian (156520) | more than 4 years ago | (#33000458)

You have done toe conversion wrong.

Its not 30 square Kilometers, it is a thousandth of that size - 30,000 Square meters.

30 Square Kilometers means 30 * 1000 * 1000 meters, or 30,000,000 Square meters - not 30 square kilometers.

 

Re:Should improve efficency! (0)

Anonymous Coward | more than 4 years ago | (#33000640)

km^2 is (km)^2, not k(m^2)

Re:Should improve efficency! (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#33000202)

Gas-fired pottery kilns can exceed 1400 Celsius, although they use a fair amount of insulation...
Wood-fired kilns on the other hand... I've seen wood kilns so hot that they literally vaporised 5cm logs as they are thrown into the firebox.
Why this is relevant? Potters use salt for some types of firing. The salt also tends to vaporise. $creator help anyone standing downwind from the kiln as the salt usually forms a sizable quantity of HCl and NaOH during combustion. (salt + smoke)

Re:Should improve efficency! (0)

Anonymous Coward | more than 4 years ago | (#33000242)

"NaCl is non-toxic"

Dreck! Ingest 10 mg of NaCl and see how you feel.

Re:Should improve efficency! (0)

Anonymous Coward | more than 4 years ago | (#33000330)

(as a side note, this is why low pressure nuclear power plants have such poor efficiency - because the water is only at 100 degrees Celsius after being heated by the nuclear fuel).

You are wrong. A PWR's (and a BWR equivalently) operating temperature is based on the pressure rating of the secondary system (for saturation temperatures). 100 degrees Celsius would imply that the pressure rating of the secondary system was only atmospheric pressure. Most reactors have an operating temperature at about 300 degrees C. Note, that for Rankine cycles, the operating temperature can't go above 375 degrees C (the critical point of water). Nuclear reactors can also be coupled to non-Rankine cycles (such as the Brayton cycle), which will allow the operating temperature to be much higher (around 1000 degrees C).

Other reasons to use salt i.s.o. oil (1)

dr.Flake (601029) | more than 4 years ago | (#33000080)

Wasn't another good reason to use salt, that molten salt has excellent thermal conduction properties??

As, you barely have to pump it around, for the heat to reach the reservoir.

Conversions... (-1)

werdnapk (706357) | more than 4 years ago | (#33000092)

Since the summary is trying to accommodate americans and the rest of the world, here are the conversions... :)

1000 degrees F = 538 degrees C
30,000 square meters = 30 square kilometers = 18.5 square miles

Re:Conversions... (4, Informative)

Anonymous Coward | more than 4 years ago | (#33000132)

30,000 square meters = 0.03 square kilometers

Re:Conversions... (0)

Anonymous Coward | more than 4 years ago | (#33000396)

Uh, no. 30,000 m^2 = 30 km^2.

Re:Conversions... (0)

Anonymous Coward | more than 4 years ago | (#33000442)

Uh, yes.

Re:Conversions... (1, Funny)

glwtta (532858) | more than 4 years ago | (#33000478)

Uh, no. 30,000 m^2 = 30 km^2.

Try again, smart guy.

Re:Conversions... (0)

Anonymous Coward | more than 4 years ago | (#33000540)

1km = 1,000m
1km^2 = 1,000m x 1,000m = 1,000,000m^2
30,000/1,000,000 = 0.03 km^2

Re:Conversions... (2, Informative)

mark-t (151149) | more than 4 years ago | (#33000180)

30,000 square meters = 3 hectares = 7.41 acres = 0.012 square miles.

Re:Conversions... (1)

rufey (683902) | more than 4 years ago | (#33000184)

Except 30,000 square meters is about 0.03 square kilometers according to Google.

It comes out to be about 7.5 acres, or 0.0115830648 square miles.

18.5 square miles would be quite large and cover an area slightly larger than 4 miles by 4 miles. That would be quite large.

Re:Conversions... (1)

phliar (87116) | more than 4 years ago | (#33000192)

30,000 square meters = 30 square kilometers = 18.5 square miles

Whoa there, buddy! I know a meter is large, but not that large! 30,000 sq m is the area of a field that is 150 m by 200 m. Which is about 500 feet by 660 feet.

Now the question is ... (0, Troll)

formfeed (703859) | more than 4 years ago | (#33000098)

... is this plant kosher?

Re:Now the question is ... (0)

Anonymous Coward | more than 4 years ago | (#33000172)

Rather ... they traded fat for hypertension?

Re:Now the question is ... (0, Flamebait)

MichaelSmith (789609) | more than 4 years ago | (#33000188)

Israel will have their own kosher molten salt power plants. Tourists will charge their video cameras before they travel.

Errr Barstow had a molten salt plant in the 90s (4, Informative)

not5150 (732114) | more than 4 years ago | (#33000120)

The article is incorrect... Barstow had a molten salt plant in 1995 I believe. Excerpt from the Wiki - "1995 Solar One was converted into Solar Two, by adding a second ring of 108 larger 95 m (1,000 ft) heliostats around the existing Solar One, totaling 1926 heliostats with a total area of 82,750 m (891,000 ft). This gave Solar Two the ability to produce 10 megawatts. Solar Two used molten salt, a combination of 60% sodium nitrate and 40% potassium nitrate," - http://en.wikipedia.org/wiki/The_Solar_Project [wikipedia.org]

Re:Errr Barstow had a molten salt plant in the 90s (3, Informative)

Anonymous Coward | more than 4 years ago | (#33000362)

Errrrr....

France had one of these, inaugurated in 1983, called "Thémis".
http://www.outilssolaires.com/pv/prin-centraleB.htm
http://fr.wikipedia.org/wiki/Centrale_solaire_Th%C3%A9mis
(danger! websites in French).

It used a circuit of molten salt, just like the OP's "world's first molten-salt solar plant"

Both this and the Barstow plant were subsequently adapted for gamma-ray astronomy (on which I work, and spent much time there).

The plant was experimental, and I believe only produced a surplus of energy on one day! It was set up ostensibly on a green agenda, but may have been done mainly to research molten salt for the Superphenix nuclear reactor (now shut down).

Re:Errr Barstow had a molten salt plant in the 90s (0)

Anonymous Coward | more than 4 years ago | (#33000394)

Probably the article should be modified to 'first commercial molten salt solar plant'
Barstow was like an experimental project.

Desalinization? (2, Interesting)

atomicstrawberry (955148) | more than 4 years ago | (#33000140)

Could this technology be combined with desalinization, i.e. take salt water, pull the salt out to produce potable water, and use the salt to improve the plant's efficiency? Desalinization is a very energy-intensive process but I wonder if a lot of that could be offset using solar and redirecting the waste salt into the energy plant that powers the process in the first place.

Re:Desalinization? (1, Offtopic)

TooMuchToDo (882796) | more than 4 years ago | (#33000178)

Yes. You could use any waste heat after the generation process to convert salt water to steam, extract the salt and sell it, and condense the steam back to water and have fresh water. Using the salt from the process might be possible, but more importantly you're desalinating water using the sun instead of diesel generators or natural gas turbines.

Re:Desalinization? (0)

Anonymous Coward | more than 4 years ago | (#33000210)

No. The molten salt is in a closed circuit. They don't consume it and they don't need more than the optimal amount which they already have.

Re:Desalinization? (4, Insightful)

DerekLyons (302214) | more than 4 years ago | (#33000388)

Could this technology be combined with desalinization, i.e. take salt water, pull the salt out to produce potable water, and use the salt to improve the plant's efficiency?

No, once the plant is charged with working fluid, you don't need to add any more.

Re:Desalinization? (0)

Anonymous Coward | more than 4 years ago | (#33000400)

You can use cheaper solar than this. Desalination works really well with low grade heat sources. See "flash evaporation desalination".

Molten salt is not new... (0)

Anonymous Coward | more than 4 years ago | (#33000142)

Themis is even a pretty old story... http://en.wikipedia.org/wiki/Themis_%28solar_power_plant%29

A big problem was to keep the molten salt to temperature especially at night, making the system consuming energy at the end of the day.

Fahrenheit... (-1, Troll)

Anonymous Coward | more than 4 years ago | (#33000148)

Only used by niggers.

It's really not competitive yet (4, Informative)

QuantumG (50515) | more than 4 years ago | (#33000170)

5MW for $60M (euro).. really?

At 10c/kWh it can earn $500/hr. So it'll only take ~13.7 years to pay it off.. oh it's solar, right, well, with the seasons and everything I guess it's more like double that. Let's say ~27 years. How much is maintenance? Oh yeah, and the time value of money.

Another way of looking at it: it's $12B/GW + operations. Nuclear power plants take 5-10 years and cost $4-10 billion to build, and $4-6 billion for fuel and operation over their lifetime, so $8B/GW to $16B/GW. So the cheapest nuclear reactor beats this by at least 35% and the most expensive nuclear reactor probably beats it also.

But that fact that they've even made it into the right ballpark is impressive and perhaps once they scale it up to somewhere that is actually useful we'll have some idea how competitive it can be.

Re:It's really not competitive yet (0, Flamebait)

Jheralack (1067056) | more than 4 years ago | (#33000260)

You are ignoring the cost to store the nuclear waste, which every nuclear advocate seems to ignore. I'm not interested in kicking the can down to the next generation (or 10!).

Re:It's really not competitive yet (1)

QuantumG (50515) | more than 4 years ago | (#33000338)

The $4-6 includes waste disposal. Actually what I'm ignoring is the cost of decommissioning the plant and that's because I have no way of estimating how much this mirror farm will cost to decommission.

Re:It's really not competitive yet (2)

ducomputergeek (595742) | more than 4 years ago | (#33000384)

If you reprocess the nuclear fuel and use breeder reactors you can power fission reactors for a few hundred years. At the end of it you end up with small amounts of hot material that remains dangerous for a couple hundred years. Not the couple eons of the current system of fueling reactors. And we're talking about hundreds of GW's of power for a couple hundred years with not a lot of waste.

We know what the costs are and as it stands, nuclear is really best form of energy for base load generation we have and we know it works.

Re:It's really not competitive yet (1)

QuantumG (50515) | more than 4 years ago | (#33000552)

Most American nuclear engineers have a low opinion of nuclear because of the once-through policy. Everyone else in the world uses their nuclear material up a lot more and store just the waste, the US stores perfectly good fuel because it might be a "strategic asset" one day. As such, nuclear in the US is legally required to be inefficient by the highest law in the land. Which is amazing, when you consider how much it still kicks butt.

Re:It's really not competitive yet (1)

Rakshasa Taisab (244699) | more than 4 years ago | (#33000264)

Can you spell the words; Prototype, Low-Maintances and Zero Emissions?

Re:It's really not competitive yet (5, Funny)

DryGrian (1775520) | more than 4 years ago | (#33000592)

Can you spell the words; Prototype, Low-Maintances and Zero Emissions?

Well, I can, but...

Sorry, couldn't resist.

Re:It's really not competitive yet (1)

BitZtream (692029) | more than 4 years ago | (#33000278)

Yep, gotta start somewhere, it'll grow I'm sure as it already has. The key is that it (well, all combined renewable energy sources) needs to grow faster than our consumption does.

I'm sure eventually that will happen as we'll run out of non-renewable fuels at which point our consumption and renewable fuel supplies will match perfectly!

Re:It's really not competitive yet (1)

TheEyes (1686556) | more than 4 years ago | (#33000284)

What they really need to do is put it in a place like the Sahara, or Death Valley, where you're assured of bright sunshine practically year round. Who in the world decided an island was the best place to put a solar plant?

Re:It's really not competitive yet (1, Redundant)

thegarbz (1787294) | more than 4 years ago | (#33000286)

It's far worse than you think. 30,000 sq m of mirrors? 3 miles of pipe? Cost aside for 5MW that is an insane amount of real estate for such little area. Our 10MW natural gas turbine at work is about 4m wide, 8m long and 7m high. Add a Heat Recovery Steam Generator to the other side of it and for a little more space you get another 7MW, and all of that still fits into a typical restaurant car park. So if you had huge amounts of disposable cash this plant would still be useless anywhere near a city, or a town, or an industry. That is a crying shame too since 5MW is so small it is basically only practical for industrial or commercial co-generation.

This seems to smell of "just because you can, doesn't mean you should"

Re:It's really not competitive yet (0)

Anonymous Coward | more than 4 years ago | (#33000558)

But this power plant leaves your children a world where they can live without growing gills.

Re:It's really not competitive yet (4, Insightful)

Darkman, Walkin Dude (707389) | more than 4 years ago | (#33000574)

Our 10MW natural gas turbine at work is about 4m wide, 8m long and 7m high.

If your natural gas turbine doesn't generate the natural gas, you aren't giving the full story here though. You also need hundreds of miles of carefully sealed pipelines and/or freight infrastructure, you also need the refining and mining infrastructure, and you need to factor in the cost for exploration and developing the mine in the first place, with all the dead ends that implies. Natural gas might be cheap but its often subsidised at source, but hey so what you say, I don't pay it. If you live in Europe and the Russians want to extract a trade agreement or something from you, the cost of that natural gas might suddenly start to fluctuate wildly however.

And thats the full story.

Re:It's really not competitive yet (5, Insightful)

Anonymous Coward | more than 4 years ago | (#33000366)

5MW for $60M (euro).. really?

That's normal. First, it's a prototype. Second, it's Italy. Third, it's Sicily.

The project started something like 20 years ago by the Nobel Prize laureate (physics) Carlo Rubbia. Seven different governments (both right-wing and center-left-wing) made every effort to cripple the project with bad management and bureaucratic issues. At the same time they poured heaps of money to dubious Sicilian consulting organisations. After a while (actually, after being dismissed from the environmental cabinet) Carlo Rubbia got tired of all these problems and flew to Spain where he built in 3 years six or seven similar plants for a tenth of their Italian price.

Re:It's really not competitive yet (1)

barv (1382797) | more than 4 years ago | (#33000576)

I can buy a 5KVA petrol Genny for about $450. So for $450,000 + fuel I could make 5MW. A course, bigger gennys would be cheaper, and more fuel efficient.

Lets face it, the future is direct conversion and efficient mass energy storage systems. Everything else is wanking.

Nothing new : France use molten salt solar plant s (0)

Anonymous Coward | more than 4 years ago | (#33000228)

http://fr.wikipedia.org/wiki/Centrale_solaire_Th%C3%A9mis

Proof of concept? (5, Funny)

T Murphy (1054674) | more than 4 years ago | (#33000268)

So in other words, they are seeing if this design is worth it's salt?

Proof of concept? (0, Redundant)

T Murphy (1054674) | more than 4 years ago | (#33000276)

So in other words, they are seeing if this design is worth its salt?

Re:Proof of concept? (0)

Anonymous Coward | more than 4 years ago | (#33000342)

:( slashdot never lagged on me before, ergo doublepost. Quick, someone come up with a joke about this power plant somehow duplicating things so I dodge the impending redundant mod.

Yeah this is OT; posting AC to reduce visibility- saves you a mod point to spend upping someone else.

$$ per watt (1)

theshiznojudge (1809572) | more than 4 years ago | (#33000310)

5 megawatts for 60 million euros (12 euros/ watt) doesn't seem worth it with photovoltaic around a third the cost, especially with the advent of mass producing polymer cells (much cheaper)

its much cheaper in reality (2, Informative)

gedw99 (1597337) | more than 4 years ago | (#33000410)

The costs for this plant are very high of course because its a new thing.

This simple power point PDF reallyshows the numbers of the solar thermal salt plant in spain that is run as a research plant.
http://www.dlr.de/tt/Portaldata/41/Resources/dokumente/institut/thermischept/Solar_Thermal_Energy_Storage_Technologies_Hannover2008.pdf [www.dlr.de]

They actually concluded that Salt is Not the only option. The problem with salt is rust, and so you have to use carbon coating on all the steel parts, which makes it expensive.

Simple using concrete was a very attractive option also.
And then that means that hemp concrete is also possible which is much cheaper again.

Re:its much cheaper in reality (1)

gedw99 (1597337) | more than 4 years ago | (#33000486)

This technology was used by a frnech female architect over 30 years ago for her projects. She used moltent salt for solar thermal storage in residential homes.

so its funny to realise that its simple and nothing new.

if you look at the design of the large Andasol plants they are the saem design as the solar thermal plant you hva in your house, JUST bigger and using hot stream, rather than water.
And of course have a steam turbine.

The other thing going on is the use of ceramic parts for the turbine. This removes the issie of the steam turning to water, and then rusting the turbine.

so, MUCH of the issues with getting the cost down is handling the rust issues with boththe wolten salt and the turbine.

Come on.. (5, Insightful)

sisko (114628) | more than 4 years ago | (#33000412)

What's this Fahrenheit rubbish?

So how much longer...? (-1, Flamebait)

SharpFang (651121) | more than 4 years ago | (#33000484)

How much longer after the Sun has gone down? A day? A week? A month?
Without a truly renewable power source we're against a dead end. Once the Sun has gone red giant, we'd better have some other -really- renewable energy sources ready.

First to use Molten Salt, Bull. (1)

John Sokol (109591) | more than 4 years ago | (#33000670)

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

Solar Two used molten salt, a combination of 60% sodium nitrate and 40% potassium nitrate, as an energy storage medium

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