Armed Polite Society
Main Forums => Politics => Topic started by: Ben on February 15, 2014, 11:06:38 PM
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Apparently this recently opened solar facility fries birds that fly near its generating towers.
A couple of fun facts that I wasn't aware of:
1) 1000 deg F of heat is apparently bled into the atmosphere? I would think you would want to try and capture some of that with double-walled towers or something. I wasn't even aware that much heat was generated. I guess this place uses some technology I'm not familiar with.
2) I knew that solar was inefficient for for large scale grid power generation, but five square miles for only 140,000 homes? Calculating just the roof space of a 1500 sq ft home (assuming single story), I get around 7.5 sq miles. so if every square foot of roof of each home was covered with solar panels (and that's probably more than an average home needs), it only takes up 150% of the space of this centralized solar plant that still has to then distribute the power all over the place. I wonder how many homes five square miles of nuclear reactors would power?
Before I get the complaints about me being a Luddite, I'm in favor of solar as a decentralized alternative energy source, e.g., individual homeowners, etc. using it. I just don't see it as a viable source of centrally distributed power, at least with present technology.
http://www.foxnews.com/us/2014/02/15/world-largest-solar-plant-burning-up-birds-in-nevada-desert/
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I wonder how many homes five square miles of nuclear reactors would power?
My quick calculations (read: SWAG) come out to: All of North America.
Ok, maybe not quite that much (calling Birdman, calling Birdman to the white courtesy phone), but the power density, in terms of the construction footprint, for solar and wind is ridiculously low. They simply take up way too much space. I think I read somewhere that a solar array that could provide all of the power for the US would be the size of the state of Ohio. Given that habitat destruction is probably one of the biggest ecological problems today, you'd think greenies would be against widespread adaptation of these technologies, but nope. :facepalm:
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It's okay when wind plants and this thing kill birds, heck, they just relaxed the incidental take permit rules for when the wind farms kill something rare. Not many golden eagles in my neck of the woods and yet everyone was still hot to build wind up here until the global bust.
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Recently opened? That place has been running for years.
However, they did recently open an additional plant right next door.
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I wonder how many homes five square miles of nuclear reactors would power?
Byron Nuclear Generating Station sits on a 1,782-acre (7.2 km², 2.784sq mile) site. It produces 2300 MWe which is enough to power over 2 million homes. So just for nice round numbers let's give everyone in the US a home (I know it's not true, but if you figure business and industrial electric consumption, it's probaly close enough.)
300 million homes / 2 million MWe= 150 Nuke Plants. That's how many Byrons we'd need.
150 * 2.784 = 417.6 sq miles. And the need to be near water and lots of it. Washington DC is 68 Sq miles. New York is 302.64 square miles (783.8 km2) and Boston is 48 square miles (124 km2). That would just enough space to power all of the US.
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1000 deg F of heat is apparently bled into the atmosphere
Does that contribute to Globular Woerming?
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Byron Nuclear Generating Station
(https://scontent-b-ord.xx.fbcdn.net/hphotos-frc3/l/t31/q80/s720x720/1402107_4989971405727_253044786_o.jpg)
That's the plume from Byron visible in the background of this pic, BTW.
My neice's kid, at my Dad's, last October.
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It's okay when wind plants and this thing kill birds, heck, they just relaxed the incidental take permit rules for when the wind farms kill something rare. Not many golden eagles in my neck of the woods and yet everyone was still hot to build wind up here until the global bust.
Yeah, I thought it almost amusing that a CA judge ruled against the enviro group that was suing over the the site. CA judges are notorious for ruling in favor of the most ridiculous cases brought before them by environmental groups. Of course if this place dealt in oil production, is there any doubt they'd be paying like $100,000,000,000 per dead bird? I am definitely amused by the environmental community in-fighting though. =D
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Byron Nuclear Generating Station sits on a 1,782-acre (7.2 km², 2.784sq mile) site. It produces 2300 MWe which is enough to power over 2 million homes. So just for nice round numbers let's give everyone in the US a home (I know it's not true, but if you figure business and industrial electric consumption, it's probaly close enough.)
300 million homes / 2 million MWe= 150 Nuke Plants. That's how many Byrons we'd need.
150 * 2.784 = 417.6 sq miles. And the need to be near water and lots of it. Washington DC is 68 Sq miles. New York is 302.64 square miles (783.8 km2) and Boston is 48 square miles (124 km2). That would just enough space to power all of the US.
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Does that contribute to Globular Woerming?
But it comes from a green source, so it's okay.
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Byron Nuclear Generating Station sits on a 1,782-acre (7.2 km², 2.784sq mile) site.
How much of that acreage is taken up by actual plant, cooling towers, etc., and how much is unused open space? Looking at it on Google Earth, I'd put the actual used space at under 0.5 square miles (0.33 sq miles by my very rough estimations using the distance legend). And even that includes parking lots (could be made smaller with parking structures) and a fair bit of unused space.
As you mention though, water availability would be a pretty big limiting factor for any sort of nuclear mega-facility.
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How much of that acreage is taken up by actual plant, cooling towers, etc., and how much is unused open space? Looking at it on Google Earth, I'd put the actual used space at under 0.5 square miles (0.33 sq miles by my very rough estimations using the distance legend). And even that includes parking lots (could be made smaller with parking structures) and a fair bit of unused space.
As you mention though, water availability would be a pretty big limiting factor for any sort of nuclear mega-facility.
Ehh, my guess was just slightly better than a total SWAG, but yeah, I bet there could be some overlap on the "Non-plant" spaces. Figure you could shoehorn at least 3 Byrons into the 5 sq mi area of that Nevada solar plant. That's enough to power 6+million homes, as opposed the 200,000 the solar plant powers now.
Byron is on the Rock River.
Lasalle is built on a 3,055-acre site with a 2,058-acre man-made cooling lake, which is also a popular fishery managed by the Illinois Department of Natural Resources.
Braidwood is built on a 4,457-acre site, and its cooling lake was formed from an old strip mine. (The area is very popular with anglers and waterfowl hunters.)
Dresden Station is located on a 953-acrea site in Grundy County, Illinois, at the head of the Illinois River.
Those four stations alone produce enough power for ~8 million homes.
Quad Cities power plant is built on 765-acre site along the Mississippi River and produces enough to power 1.5 million homes.
Clinton sits on a 14,300 acres site and adjacent 5,000 acre cooling reservoir; Clinton Lake, which is owned by the operator, but hosts the Clinton Lake State Recreation Area and is open to public for a large range of outdoor activities. Only around 150 acres are actually used by the plant's buildings and operation areas. It produces enough for about 1 million homes.
So using the largest acreage numbers, we have a total of 39.55 sq miles (and keep in mind more than half that is usable recreational land/water.) Which powers 10.5 million homes. And that power is there 24/7/365, without fail; even with clouds, rain, or dark of night. To get the same amount of non-reliable power from solar we'd need 262.5 sq miles of solar arrays. And it would have to be sunny 24/7/365.
That Solar Plant just doesn't make sense.
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Does that contribute to Globular Woerming?
No, that heat was going to the earth anyway.
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No, that heat was going to the earth anyway.
CO2/greenhouse effect is just keeping the heat that was already there =D
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(ever so slightly off-topic)
Unintended consequences of bending and bouncing light around my place. Mile-high altitude, midsummer, 0% sky cover:
1. Drying silverware (I handwash stuff) in a highly polished steel colender out on my balcony. I noticed smoke coming from it through my kitchen window. A small portion (3-4 in^2) of the colender was exposed to the sunlight and focused it on the plastic handle of a steak knife, melting it and generating the smoke.
2. There are several documented instances of crystal balls left in sunlight starting fires. Most often, this is because the ball was left on a windowsill and its focus fell on closed drapes. In one case, the ball was left on a couch and started a fire in the couch. (For most glass, the focal point of a sphere is about 1/3 radius from the surface, M/L.) I have no documentation of other glass knick-knacks causing the same problem, but it seems possible.
3. I had a flashgun from a Brownie camera, where the 6 in diameter parabolic reflector would make a piece of paper burst into flame in a matter of less than 10 seconds or so.
4. In light (no pun) of the above wisdom, I got a little concerned about the possibilities of 2-liter bottles filled with water focusing sunlight on flammable surfaces. (I keep emergency water in these bottles out on the back balcony.) Even though the focal point was a "focal line" instead of a point, I measured the temp at this line at around 120°F by thermocouple. Not too dangerous, but I left the labels on the bottles after that to keep the light from going through.
5. A long time ago I discovered that bending a 4X8 sheet of 1/4in Masonite along its long axis resulted in a near-perfect two-dimensional parabolic shape. Applications are obvious.
Question: What would you call that flat array of steerable mirrors to focus light like a parabola? A "Fresnel" mirror?
Dinnertime now.
Terry, 230RN
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Using Clinton station as an example, it only needs 150 acres for the actual buildings and plant. Let's see 5 sq mi = 3200 sq acres. 3200/150=21.333333
So we could actually fit 21 Clinton generating stations into 5 sq miles (assuming it was somewhat linear and along a large body of water).
That's 21+million homes powered vs 200,000, that's a 10500% land utilization improvement.
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How much of that acreage is taken up by actual plant, cooling towers, etc., and how much is unused open space? Looking at it on Google Earth, I'd put the actual used space at under 0.5 square miles (0.33 sq miles by my very rough estimations using the distance legend). And even that includes parking lots (could be made smaller with parking structures) and a fair bit of unused space.
As you mention though, water availability would be a pretty big limiting factor for any sort of nuclear mega-facility.
Acreage is not a real concern. Cooling, security, convenience and aesthetics are. If you really really needed the space, a modern commercial power nuclear power plant could be condensed to a couple acres (to include all support and personnel requirements). If you go hog wild and lower your power requirements, it'd fit in a room. Except for the Navy, there's no need and plenty of drawbacks. Birdman and I talked about it once. I think the guesstimate is maybe 225 square miles (15 mile by 15 mile), IF it has adequate cooling. In his opinion (I'm not a synthetic fuel expert), you'd need a hundred by hundred square to make all the power AND hydrocarbon fuel America would need, at a cost of around $10 trillion.
Theoretically, if you used a river or ocean, you could get your uranium from the water as well. =D
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I would think the FAA would eventually get irritated about a bunch of mirrors everywhere interfering with aircraft visibility.
Also, for that desert solar station, I wonder how many desert animals have taken to living under the shade of all those mirrors.
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1) 1000 deg F of heat is apparently bled into the atmosphere? I would think you would want to try and capture some of that with double-walled towers or something. I wasn't even aware that much heat was generated. I guess this place uses some technology I'm not familiar with.
Focusing sunlight can make a *lot* of heat. IIRC, one of the home experiments with tiling small flat mirrors on a ~8ft satellite dish generated enough to get iron at the focal point red hot.
I knew that solar was inefficient for for large scale grid power generation, but five square miles for only 140,000 homes? Calculating just the roof space of a 1500 sq ft home (assuming single story), I get around 7.5 sq miles. so if every square foot of roof of each home was covered with solar panels (and that's probably more than an average home needs), it only takes up 150% of the space of this centralized solar plant that still has to then distribute the power all over the place.
Home solar requires proper planning. Remember that only solar on the roughly south facing roof pitches will generate at anywhere near rated efficiency, and also remember that some freaks are overly fascinated by roofs so complex that it's near impossible to install effective solar arrays. That said, a good design with a large, open south facing pitch can easily generate more than the home needs if it's using some basic efficiency improvements. (Good A/C, CFL or LED lighting mainly to avoid the excess heat generated by incandescents, gas heat, gas tank type or electric tankless water heater, etc.)
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I've always wondered about putting substations and transmission lines at the several naval stations that host nuclear powered vessels, backfeed the grid, run the plants at capacity while in port. Would shorten the re-fueling cycle, but it's not like we'd run out of cooling water. More porky shipyard jobs doing re-fuels, sounds like a plan Bobby Scott et. al could vote for.
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Back to the OP, I wonder if they taste like chicken?
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I've always wondered about putting substations and transmission lines at the several naval stations that host nuclear powered vessels, backfeed the grid, run the plants at capacity while in port. Would shorten the re-fueling cycle, but it's not like we'd run out of cooling water. More porky shipyard jobs doing re-fuels, sounds like a plan Bobby Scott et. al could vote for.
Oh, there's an example of that. Some aircraft carrier berthed itself by some city without power and cabled itself to the local power grid as an emergency supply. Forget details for right now.
ETA: Found it. Here it is, and this wasn't the last time this scheme was used:
http://www.historylink.org/index.cfm?DisplayPage=output.cfm&File_Id=5113
Supplied 25% of the city's power for a month.
MORE:
http://search.tacomapubliclibrary.org/images/dt6n.asp?krequest=subjects+contains+Aircraft%20carriers
Terry, 230RN
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Oh, there's an example of that. Some aircraft carrier berthed itself by some city without power and cabled itself to the local power grid as an emergency supply. Forget details for right now.
ETA: Found it. Here it is, and this wasn't the last time this scheme was used:
http://www.historylink.org/index.cfm?DisplayPage=output.cfm&File_Id=5113
Supplied 25% of the city's power for a month.
Terry, 230RN
One of the reasons they send acft carriers to disaster zone's, along with their ability to desalinate 400,000 gallons (IIRC) of water per day.
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You don't actually 'need' a large source of water for a nuclear plant. It's just substantially cheaper on the cooling systems. Build the cooling systems heavier and you don't need to heat/evaporate water in order to dispose of the heat. This can work even in the desert, and as a bonus they'd be a couple percent more efficient.
I was debating this issue on a forum called 'spacebattles'. Somebody posted a link to a French nuclear reactor under construction - $11B with cost over-runs(it's something of a prototype).
Some financial notes:
The nuclear reactor is rated for 4 times the power at 5 times the cost
The solar plant would have an estimated capacity factor of 31 percent. Which means that you take the faceplate capacity times 365*24*31% in order to figure out the average amount of energy it'll produce in a year. Nuclear plants average roughly 90% - so on a kwh per year comparison, you need 3 watts of solar to match 1 watt of nuclear.
The solar plant should produce 1GWh per year(wiki site). The nuclear plant? 13GWh. 13 times the energy at 5 times the cost? Pretty good deal.
Ivanpah doesn't even include any power storage so it can continue producing power for a significant period of time after the sun goes down, occluded, etc...
I'll note that this doesn't necessarily mean that Ivanpah won't be useful - power usage in the south does trend higher when the sun is out due to AC systems and such. So if you look at it as a sort of peaker, it's not necessarily bad. In any case now that it's built you might as well use it.
On the fancier, more advanced fronts: Conventional nuclear plants are about 30% efficient at turning heat into electricity. This means that a 1GWe nuclear plant is actually 3GWt. Unless you turn it into a co-generation plant where you use the heat for something(which would involve building industry/facilities too close to plants for current concerns), you need to dispose of 2GWt, that's the expensive part, water wise.
The efficiency of turning thermal energy into electrical energy is limited by the Carnot Cycle. Conventional water cooled designs simply can't get that hot due to the pressure necessary to keep the water liquid. PWR/BWR runs at around 315C, which translates to 49% efficiency, but that's the theoretical max. 70% of it is more real world, 34% efficient. Go to molten salt (http://en.wikipedia.org/wiki/Molten_salt_reactor), Very high temperature reactor (http://en.wikipedia.org/wiki/Very_high_temperature_reactor) gives you temperatures from 700 to 1000C.
700C gives you a max of 69%, 48% real world
1000C would be 76% and 53%. At this point lowering the temperature of your heat sink(assuming 27C here) would have more effect.
What's the big deal? Going from 30 to 50% efficiency means that you no longer need a 3GWt plant to produce 1GWe. You now only need a 2GWt plant to produce 1GWe. 1GWt to dispose of is half what you needed to get rid of before, the plant can be smaller, etc...
Another positive of getting away from water as a coolant is that you can switch to materials that don't need to be pressurized to stay in the desired state. That means that you don't need an incredibly strong pressure vessel that's at risk of exploding when something goes wrong. Hell, on the high end the reactor core is essentially pre-melted. The higher design temperatures also means that the reactor vessel is a very good radiative body - passive cooling to prevent breach is easy.
Another crazy design I've heard of is building the reactor into a barge and operating it semi-submerged as normal. Only works around coasts though.
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That's why tapping our SSNs would be so much fun. Something goes wrong, sink it at the pier. It's the Elizabeth River, not like anyone would notice a little extra glow. =D
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4. In light (no pun) of the above wisdom, I got a little concerned about the possibilities of 2-liter bottles filled with water focusing sunlight on flammable surfaces. (I keep emergency water in these bottles out on the back balcony.) Even though the focal point was a "focal line" instead of a point, I measured the temp at this line at around 120°F by thermocouple. Not too dangerous, but I left the labels on the bottles after that to keep the light from going through.
I've seen that with small water bottles. More correctly, I've smelled it. In an airplane I was flying. It was a bit disconcerting.
I would think the FAA would eventually get irritated about a bunch of mirrors everywhere interfering with aircraft visibility.
I have flown over that solar power station referenced in the OP a few times. It isn't a factor because the light is focused at the top of the tower. At 30,000+ feet, the light is bright but not a nuisance.
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On the fancier, more advanced fronts: Conventional nuclear plants are about 30% efficient at turning heat into electricity. This means that a 1GWe nuclear plant is actually 3GWt. Unless you turn it into a co-generation plant where you use the heat for something(which would involve building industry/facilities too close to plants for current concerns), you need to dispose of 2GWt, that's the expensive part, water wise.
The efficiency of turning thermal energy into electrical energy is limited by the Carnot Cycle. Conventional water cooled designs simply can't get that hot due to the pressure necessary to keep the water liquid. PWR/BWR runs at around 315C, which translates to 49% efficiency, but that's the theoretical max. 70% of it is more real world, 34% efficient. Go to molten salt (http://en.wikipedia.org/wiki/Molten_salt_reactor), Very high temperature reactor (http://en.wikipedia.org/wiki/Very_high_temperature_reactor) gives you temperatures from 700 to 1000C.
700C gives you a max of 69%, 48% real world
1000C would be 76% and 53%. At this point lowering the temperature of your heat sink(assuming 27C here) would have more effect.
What's the big deal? Going from 30 to 50% efficiency means that you no longer need a 3GWt plant to produce 1GWe. You now only need a 2GWt plant to produce 1GWe. 1GWt to dispose of is half what you needed to get rid of before, the plant can be smaller, etc...
Yea, except the salt turns solid, life is going to suck. Birdman downplayed my concerns on corrosion and I believe him, but I'm still very "eh..." on that subject. I believe it will be a concern. I'm not sure of embrittlement issues, I'd have to ask a materials science person on that one.
Also, doesn't it require a fairly uninvolved chemical plant?
Water sucks for thermal transport. Yet everyone keeps going back to it. PCs, data centers, nuclear reactors, etc.
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Water sucks for thermal transport. Yet everyone keeps going back to it. PCs, data centers, nuclear reactors, etc.
Well, I'm sure if we had oceans full of mercury, we'd use it more often.
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Well, I'm sure if we had oceans full of mercury, we'd use it more often.
And Mercury has no oceans =(
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Well, I'm sure if we had oceans full of mercury, we'd use it more often.
Excellent point
Sent from my Electric Brick using Tap-a-Crap
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Water actually isn't so bad for heat transport as long as a phase change is involved. If you are boiling off steam and then using that to generate more power, it is pretty good. I am sure other chemicals would work if they were cheap enough and easy to handle and non-toxic.
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Water actually isn't so bad for heat transport as long as a phase change is involved.
Therein lies the problem with about 90% of the things that are water cooled; they just use it as a liquid for transport, without taking advantage of the huge absorption/dump that happens at evaporation/condensation.
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Water sucks for thermal transport. Yet everyone keeps going back to it. PCs, data centers, nuclear reactors, etc.
Actually, it has a very high specific heat, 2nd best after ammonia, the latter presenting its own nasty problems.
Then there are the other "friendly" alternatives like liquid metals, freon, etc.
Of course, having a planet with 71% of its surface covered with water helps a smidgen, too...
I'd like to find a pump and cooling system for my workstation that can handle mercury. Probably flex the CPU sockets right off the motherboard! :O
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Yea, except the salt turns solid, life is going to suck.
Why? That's how it starts out; the plant would have heating systems specifically for that.
Birdman downplayed my concerns on corrosion and I believe him, but I'm still very "eh..." on that subject. I believe it will be a concern. I'm not sure of embrittlement issues, I'd have to ask a materials science person on that one.
That's why there's still R&D efforts on it.
Also, doesn't it require a fairly uninvolved chemical plant?
For reprocessing? Fairly involved, but not insurmountable.
Water sucks for thermal transport. Yet everyone keeps going back to it. PCs, data centers, nuclear reactors, etc.
It's actually quite good at it. It has a high specific density, isn't especially corrosive or flammable, is easy to pump, the issues with it are known, etc.... It's when you start getting out of it's ideal temperature range that issues crop up.
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I apologize if I poorly phrased. I didn't mean to sound like water was a poor choice for thermal transport. Quite the opposite. Every time I near some new fancy thermal transport system, like molten salt or whatnot, I always just shrug and assume they'll go back to water. I've heard the pitches before. Nonconductive liquids for PCs and data centers, molten salt reactors, etc.
Is it possible to do? Absolutely. Will it become common? Meh, I have my doubts.
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I was bored, so I am striking from orbit.
Nonconductive liquids for PCs and data centers, molten salt reactors, etc.
Water (pure) is non-conductive, that is why its used as an insulator and dielectric in ultra-high voltage machines.
Actually, it has a very high specific heat, 2nd best after ammonia, the latter presenting its own nasty problems.
Depends what you mean, and how its measured, and at what temperature, at room temperature, liquid water is 3rd best, after gaseous Hydrogen(3+x better) , Helium (20% better). Gaseous ammonia is 1/2 that of water, and about the same as methane.
Liquid helium obliterates EVERYTHING in terms of specific heat. Liquid hydrogen is pretty good as well, on a per mass basis.
Water actually isn't so bad for heat transport as long as a phase change is involved.
Given its relatively wide liquid range, that at the lower end covers normal heat rejection temperatures, its actually a near ideal fluid for heat transfer (also, low viscosity, relatively high density, and high thermal conductivity help), regardless of phase change.
Well, I'm sure if we had oceans full of mercury, we'd use it more often.
Actually NaK is far superior to mercury if going the liquid metal route. Mercury's low specific heat makes for HUGE up power requirements. Also, its high vapor pressure causes issues in design, which is why if going the liquid metal route, others are typically chosen.
1) 1000 deg F of heat is apparently bled into the atmosphere? I would think you would want to try and capture some of that with double-walled towers or something. I wasn't even aware that much heat was generated. I guess this place uses some technology I'm not familiar with.
You can't really do anything about it, its a matter of absorptivity (of solar spectrum light) vs emissivity (of blackbody radiation at the temperature of the absorber.
In fact, this ratio defines the -maximum- efficiency of a solar-thermal solution.
Sunlight corresponds to a blackbody in the 5300K range, so ideally you want something that has absorptivity of 100% at those dominant wavelengths (I.e., black), BUT absorptivity EQUALS emissivity at a given wavelength, so you then want something that has low absorptivity at longer wavelengths (e.g. 1.5-3+ microns for a 1000C collector), but, without resorting to photonic crystals (way too expensive for this large scale application), you are pretty much stuck with graphitic, ceramic, or refractory metals (coated with absorbing ceramics), as such, you pretty much get a flat emissivity curve. Thus, at most, ~85-90% of the incoming sunlight (regardless of concentration) gets turned into heat in the absorber, and the higher the temperature, the MORE you lose there...so its competing efficiencies (absorption efficiency vs heat engine efficiency).
Note, photovoltaic cells suffer from similar effects. A given semiconductor only will generate a photo-electron for wavelengths -shorter- than it is tuned for, and then only one per photon. So for a continuous spectrum (sunlight) you need a stack of cells to make maximum use of the incoming light.
The shortest wavelengths are absorbed first, then progressively longer as you go "into" the stack, with cell voltage roughly inversely proportional to wavelength.
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Either way, the original post mentioned 5 square miles of solar plant to power 140,000 homes. I was thinking that 140,000 homes might fit into 5 square miles or not a whole lot bigger footprint. You certainly are not going to clear 5 square miles anywhere around the East Coast to build a solar plant unless you go off shore. You couldn't do it on the Gulf Coast either. What isn't covered in homes is designated as wild life habitat or something.
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What isn't covered in homes is designated as wild life habitat or something.
Yeah, but don't you know that it's okay to destroy the environment if it's for the environment?
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Yeah, but don't you know that it's okay to destroy the environment if it's for the environment?
Hence, the controlled grass fires they do occasionally.
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As it happens, I spent a bit of Friday morning designing 10kW racks for regular 280W PV panels to be the base unit of a proposed 5MW farm. Based on my minimum spacing (for shading and maintenance access) requirements, 5 square miles would hold a bit over 913MW of PV. (ETA: at our regular price - not accounting for the huge economies of scale on a project that size - 913MW would be around $2.7 billion. I'm betting we could do at least 800MW 100% turnkey for the $2.2 billion they paid for 400MW.)
PV also has the advantage of not needing to be all in one spot; part of the point of this rack is that you could simply throw a 10kW inverter on each one and operate them entirely independently. The rack itself would be roughly 82 feet E-W and less than 12 feet N-S, so no need to bulldoze neighborhoods when you could put them over alleys, bus stops, whatever. (20x40' is our regular 10.08kW rack size for single-rack ground mounts, so there are options for size and coverage too.)
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As it happens, I spent a bit of Friday morning designing 10kW racks for regular 280W PV panels to be the base unit of a proposed 5MW farm. Based on my minimum spacing (for shading and maintenance access) requirements, 5 square miles would hold a bit over 913MW of PV. (ETA: at our regular price - not accounting for the huge economies of scale on a project that size - 913MW would be around $2.7 billion. I'm betting we could do at least 800MW 100% turnkey for the $2.2 billion they paid for 400MW.)
PV also has the advantage of not needing to be all in one spot; part of the point of this rack is that you could simply throw a 10kW inverter on each one and operate them entirely independently. The rack itself would be roughly 82 feet E-W and less than 12 feet N-S, so no need to bulldoze neighborhoods when you could put them over alleys, bus stops, whatever. (20x40' is our regular 10.08kW rack size for single-rack ground mounts, so there are options for size and coverage too.)
$3/peak watt sounds good, until you look at the average generation, then its more like $8-12/watt, not including O&M and WAY not including storage.
Now, accounting for average insolation, to power the US, we would only need...let's see...30-50,000 square miles, at a cost of $20-30 trillion, and for overnight storage, -just- 1000+ Hoover dams operating as pumped storage that drain-fill leak mead once per day.
Solar sucks for large power.
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As it happens, I spent a bit of Friday morning designing 10kW racks for regular 280W PV panels to be the base unit of a proposed 5MW farm. Based on my minimum spacing (for shading and maintenance access) requirements, 5 square miles would hold a bit over 913MW of PV. (ETA: at our regular price - not accounting for the huge economies of scale on a project that size - 913MW would be around $2.7 billion. I'm betting we could do at least 800MW 100% turnkey for the $2.2 billion they paid for 400MW.)
PV also has the advantage of not needing to be all in one spot; part of the point of this rack is that you could simply throw a 10kW inverter on each one and operate them entirely independently. The rack itself would be roughly 82 feet E-W and less than 12 feet N-S, so no need to bulldoze neighborhoods when you could put them over alleys, bus stops, whatever. (20x40' is our regular 10.08kW rack size for single-rack ground mounts, so there are options for size and coverage too.)
Got any suggestions for something in the 85-100 W range for charging a couple of big deep cycle marine batteries on a sailboat?
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ETA: at our regular price - not accounting for the huge economies of scale on a project that size - 913MW would be around $2.7 billion. I'm betting we could do at least 800MW 100% turnkey for the $2.2 billion they paid for 400MW.
Just analyzing here, did you figure in land acquisition costs, the need to build infrastructure to get the panels into the previously undeveloped area, and the power lines needed to ship the power out of the site?
Not saying the project isn't a boondoggle anyways, but they are expenses that need to be taken into account.
over alleys, bus stops, whatever. (20x40' is our regular 10.08kW rack size for single-rack ground mounts, so there are options for size and coverage too.)
One of my favorite ideas after spending some time in the UAE is the idea of covered parking lots - I loved the covered parking there, it saves so much stress on vehicles if you at least keep them out of direct sun. As an ancillary to this it shouldn't take much to have the covering material be a solar panel as opposed to a metal roof.
Wham, your car is kept cool during the day, parking lots aren't heat zones warming up the entire city(or at least as much), your vehicle is a lot less likely to be rained on, you save wear&tear on the paint, don't come back to a car that's hot enough to melt common plastics, etc...
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Got any suggestions for something in the 85-100 W range for charging a couple of big deep cycle marine batteries on a sailboat?
Not really; 235W is as small as we go, since the cost per watt even in bulk is awful below that size.
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Solar sucks for large power.
No, it sucks as a sole source. What it does extremely well is balance out the daily variation in the production/demand ratio by producing at peak when demand is highest.
Of course, ignoring the changes in demand throughout the day also skews the numbers for storage/supplement capacity. We see that a lot with off-grid estimates, where storage capacity assumes that people will want a CRT TV and A/C running full blast all night long.
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Just analyzing here, did you figure in land acquisition costs, the need to build infrastructure to get the panels into the previously undeveloped area, and the power lines needed to ship the power out of the site?
All of that is well outside our specialty, so we leave anything beyond construction and delivering the power to a specified point on the property up to the buyer. I do have a contact at a utility-scale power transmission contractor, but I just refer the customer to them and go back to my design and steel purchasing.
One of my favorite ideas after spending some time in the UAE is the idea of covered parking lots - I loved the covered parking there, it saves so much stress on vehicles if you at least keep them out of direct sun. As an ancillary to this it shouldn't take much to have the covering material be a solar panel as opposed to a metal roof.
Carports and RV covers are about half of our residential ground mount business, and commercial covered parking is quite a popular product as well. When you figure the cost of a large carport, then factor in the power company incentives and Federal tax credit, (all of which apply to the support structure as well when it's built as part of the solar purchase) a lot of our customers are getting a deal that's too good to pass up compared to just building a regular carport.
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Not really; 235W is as small as we go, since the cost per watt even in bulk is awful below that size.
Shoot me a link if you do any retail type stuff, I could go bigger.
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Shoot me a link if you do any retail type stuff, I could go bigger.
We don't have any of that stuff listed, since most of our retail is full kits of one sort or another. We can definitely sell you one, but I'd expect that shipping on a bulky (shipping dims usually 6'x3'x1') 50lb item would kill our price advantage over a vendor close enough for you to pick it up.