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Largest Sodium Sulfur Battery Powers a Texas Town
separsons writes "The largest sodium sulfur battery in America, nicknamed 'BOB,' can provide enough electricity to power all of Presidio, Texas. Until now, the small town relied on a single 60-year-old transmission line to connect it to the grid, so the community frequently experienced power outages. BOB, which stands for 'Big-Old Battery,' began charging earlier this week. The house-sized battery can deliver four megawatts of power for up to eight hours. Utilities are looking into similar batteries to store power from solar and wind so that renewables can come online before the country implements a smart grid system."
the battery would cost 25M, while a second transmission line would cost 60M. o_O
Yes, I'm left. You have a problem with that?
I realize your kids may think it's funny to say that your whole town's on acid, but is this really the best solution, or was it just the cheapest. And I assume there was no need for an environmental assessment, as this is Texas...
Sleep your way to a whiter smile...date a dentist!
with a mechanical bull, some baking soda and a steady stream of beany flagellants.
can't really remember if we used vinegar or not but there was definitely a little foam.
glad other people are catching on...
Bob is reminiscent of TIM's power solutions. http://en.wikipedia.org/wiki/The_Incredible_Machine
Talk about shooting the rope that's tied to a balloon that hits the hamster cage, that turns the treadmill, that throws the basketball onto the lightswitch to turn on the light!!!
Science advances one funeral at a time- Max Planck
The house-sized battery can hold four megawatts of power for up to eight hours.
I wasn't sure what that was supposed to mean. Does the battery discharge in 8 hours if you don't use the energy?
The original NPR article http://www.npr.org/templates/story/story.php?storyId=125561502 leads me to think they are saying that the consumption of the town is 4MW and the battery can feed it for 8 hours, so it holds 32MW (or less, since the 4MW is the peak load).
On an unrelated note, why does the inhabitat article have four links, which all go to the same popsci article? Does the author get paid by the link?
It's been a long time since I last heard about Sodium/Sulphur batteries. Twenty-plus years ago Ford Aerospace in Newport Beach, CA had a small research facility looking at this technology. The smell of sulphur was pretty strong around that building which was cleverly situated both downhill and downwind from the rest of the campus. The idea of being anywhere in the neighborhood of a bunch of hot,liquid sodium and a bunch of hot,liquid sulphur somehow never seemed like a good idea to me.
It's amazing the game of telephone that happens when blogs steal news stories from blogs that steal news stories from blogs.
Inhabitat: "Electric Transmission Texas ponied up $25 million to build the battery, and will add $60 million to build a second transmission line by 2012."
PopSci: "Electric Transmission Texas helped put the battery project together for around $25 million. But the utility has also agreed to build a second 60-mile transmission line to Presidio for about $44 million by 2012."
NPR: "The other solution for this town would be to build a second line, and that line would cost somewhere in the range of $40 to $50 million. And so a battery project in the $25 million range looks pretty attractive."
They all agree the battery costs $25mill, 2/3 agree that the 2nd transmission line will be built in 2012, and none of them agree on the price of the 2nd line.
Bob? Microsoft Bob, it that you?
so it holds 32MW
No - it can hold 32MWh (=115.2GJ). Batteries hold energy not power. Since power is energy per unit time you have to multiply it by a time to get energy.
That is extremely unlikely- that's a LOT of heat.
A Watt is a power unit. A Watt-hour is a energy unit. They most likely meant it is a 32 Megawatt-hour battery.
On an unrelated note, nobody seems to have pictures of the finished thing, or how it was constructed, etc- just one picture of a concrete shell, clearly early in the process. Anyone find more pictures?
Please help metamoderate.
so it holds 32MW
No - it can hold 32MWh (=115.2GJ). Batteries hold energy not power. Since power is energy per unit time you have to multiply it by a time to get energy.
Thank you, 007, for clearing up this little misunderstanding.
I wonder how long this battery will last and what the cost of a refurbishment is. Also, how does the lifetime change with more dischare/charge cycles? I think these numbers are as important as the initial cost, but usually do not get mentioned.
A $25M batter which lasts 50 years sounds like a pretty nice piece of technology if it can be discharged/charged daily. If it lasts 5 years and has a 100% refurbishment cost, it does not sound so great.
Todd
Omne ignotum pro magnifico.
"The house-sized battery can hold four megawatts of power for up to eight hours."
"Power" is not "held." Power is delivered. Energy is held. The unit of energy is joule.
Talk about shooting the rope that's tied to a balloon that hits the hamster cage, that turns the treadmill, that throws the basketball onto the lightswitch to turn on the light!!!
In Dwarf Fortress, you turn the switch, that opens the door, that lets the goblin in, who steps in the pressure plate, that connects the windmill, that pumps the magma, that runs under the water, that evaporates, passes through the grates, incinerates the goblin, who releases the pressure plate, closes the door and resets the trap.
Or that's what the engineer described before flooding half the fortress and turning the other half into a convoluted basalt sculpture.
This story originally came from an NPR interview. Here is a link.
Should the device explode, given the amount of energy stored inside the battery and the kind of chemicals employed in the facility, it could level out the surroundings. Furthermore keeping it underground should make easier to cool the device while charging.
Seriously, guys, are you that desperate for views?
The article linked to in the summary got the article from PopSci, who got it from NPR.
That aside... They should probably just stick a little reactor nearby to power their community and other nearby communities. Maybe even sell some power to Mexico.
I'm sure they've got enough wasteland that you could build one on without causing too much damage to human settlements in the region (which is all the NIMBYists care about).
BUB might be a better nickname. Big Unexploded Battery.
I'm sure it's safely enclosed and all the safety aspects have been taken into account, but it will be an impressive boom when it does go off, assuming the size of the boom goes up proportionally with the size of the battery (I had a tiny watch battery blow my little remote control car apart...)
This thing cost 25 million to make and apparently stores 192000 KWHr of energy. That is $130/KWHr. On average my home uses 17 KWHr/day so I can store my average needs for only $2210.00.
Thats a small additional cost on the 6 KW of Peak Power worth of PV's I need to provide the 17 KWHr for my house.
Does this thing scale down?
Not based on the $25 million sticker price: that's just bullshit accounting. I'd like to know the Joules expended in the extraction, refining, shipping and construction of this thing, including the energy required by the workers, then let's compare that to the energy that it will actually store and deliver over its working life.
Eventually, we are going to have to start asking these questions about "renewable" generation and storage, because you can only hide a net energy loss in the books for so long, until the fossil fuels that subsidise these energy sinks start to run out.
If you were blocking sigs, you wouldn't have to read this.
"presidio" (Spanish) = "prison"
Nice place to live.
How long would it power an iPad?
They can last about 2,500 complete cycles or 4,800 80% discharge cycles. (From the wikipedia article linked elsewhere). Presuming a power outage once a week requiring 80% discharge, it would last about 90 years, if the number of cycles is the only thing determining its longevity.
Everything is bigger in Texas...
Look in any computer shop and you'll see NaS storage systems!
They can last about 2,500 complete cycles or 4,800 80% discharge cycles. (From the wikipedia article linked elsewhere). Presuming a power outage once a week requiring 80% discharge, it would last about 90 years, if the number of cycles is the only thing determining its longevity.
That is 10-15 years when used as a night-time backup for solar collection.
This might be useful.
-Todd
Omne ignotum pro magnifico.
Flywheel energy storage (FES) works by accelerating a rotor (flywheel) to a very high speed and maintaining the energy in the system as rotational energy. When energy is extracted from the system, the flywheel's rotational speed is reduced as a consequence of the principle of conservation of energy; adding energy to the system correspondingly results in an increase in the speed of the flywheel.
- http://en.wikipedia.org/wiki/Flywheel_energy_storage
Maraging steel, UHMWPE, and carbon fibres are some of the materials with the highest known tensile strength. The higher the tensile strength, the higher the energy density, which is good for mobile applications but perhaps not necessary for a small town.
I suspect a flywheel would also be more reliable and environmentally friendly than most batteries.
All rites reversed 2010
I'm curious as to why they used Sodium Sulfur rather than Vanadium Redox.
I'm unaware of any advantages to S.S. except maybe size (which wouldn't particularly matter in a stationary installation. And the Vanadium Redox is already productized for exactly this service.
Maybe too much patent encumberment and the guys with the V.R. patent don't have enough production capacity or are charging too much?
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Flywheels could also have been used. I'll expect those to pop up next to gas stations as electric cars will replace gas-guzzlers. Easy to store energy slowly over long time and rapid dischagre for rush hours.
More power to them.
This battery should be able to last a very, very long time without losing significant capacity. It's also a big enough battery that it can be refurbished rather than just being tossed when it's used up.
Try doing a Google streetview on that place. God what a dump. It doesn't even seem to have some kind of a city centre, houses are just all over the place, with huge empty pieces in between.
10 ?"Hello World" life was simple then
Sorry, I don't speak metric. What's that in ampere-parsecs?
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
The units in the summary are meaningless and uninteresting to almost everybody, and make science geeks twitchy. I propose several alternatives.
For physicists and engineers:
8 hours = 28800 s
W=PT
=4e6 W * 28800 s
=115.2 GJ
For people who measure energy in electricity bills: 3200 kW h
For people who like impressive comparisons: About 2 M-29 Davy Crocketts.
# cat
Damn, my RAM is full of llamas.
They've put the entire town on a UPS. We need this technology here in India...
So you're saying instead of smelting metal, making concrete, and paying construction workers to build the battery, it might be more cost effective to pay that same smelting facility, concrete making plant, and construction workers to provide a few hours of power for this town every week or so?
I doubt this project has anything to do with "renewable" but all to do with convenience of not having to lose power for a few hours every few weeks. Sure those few hours may be 10x as expensive as normal, but, eh, you don't have to adjust clocks on all those VCRs every week.
"If anything can go wrong, it will." - Murphy
is to use, of all things, water. One keeps two reservoirs, one higher than the other. While one has power, one pumps water from the lower to the higher. When the power cuts out, one generates hydroelectric power by allowing water through from the higher to the lower.
What makes you think we will "run" out of fuel sources?
We burned tr... we STILL burns trees even now.
Dried grasses and plants, another one.
Fur, fat and skins of animals, another.
A little stone or metal to generate a spark is all you need.
All that will happen will be the poorer, and the less knowledgeable of communities will die out. (with the civil wars and such)
These fires can still generate decent flames required for most of societies needs.
Hell, if it wasn't, we wouldn't even be around using these computers now, neither would the human race for that matter.
Its just the numbers of people that is the concern, and that will naturally balance itself out anyway.
Screw all that "carbon neutral" bullshit, stop buying human-caused warming crap, warming is and always has been natural.
It will continue to happen with or without human intervention, all i can tell you is we probably will end up being the death of this planet by trying to stop processes that have happened from before there was even life on Earth.
Whether it is a huge mirror in space, or bubbling up the oceans to make them reflect more, we will wreck this planet by trying to stop it from doing what it does.
Instead of trying to stop it, we should be preparing for it and a possible (LATE) Ice age in the near future.
I'm not saying anything, I'm asking a question. It's one which is rarely asked, and almost never answered. You'll note that I discounted (dollar) "cost" right up front - I'm only interested in energy. You'll further note that the article explicitly talks about using BOBs as storage for renewable generation.
If you don't know the answer, you could just say so.
If you were blocking sigs, you wouldn't have to read this.
Let's do the math here.
The article suggests the battery can put out 4 megawatts for 8 hours. So that's 32,000 kilowatt-hours. My electricity here costs about 7 cents a kWh, so that BOB can hold almost $225 worth of electricity. At a cost of many millions, that does not sound like very economical power per kWh!
For example, your basic Honda generator can run for two thousand hours, putting out 1,500 watts, before the little putt-putt engine needs an overhaul. So that's about 3,000 kilowatt-hours for $400. Let's assume the power fails ten times a year, so you'd wear out 10 Honda generators per failure (avg), at a cost of $4000 per, or $40,000 per year. By comparison BOB's cost of financing in itself is going to be at least $3 million a year, not to mention maintenance.
So these poor sods are paying about 75 times as much as they should.
( Not to mention that generators are much more economical in larger sizes )
The $25 million is an excellent proxy for the maximum amount of energy used to produce it.
Nerd rage is the funniest rage.
I see that nobody is imagining a Beowulf cluster of BOBs...
The $25 million is an excellent proxy for the maximum amount of energy used to produce it.
Not really. Price is determined by energy AND rarity. Raw material prices fluctuate wildly. I have a hard time believing that the energy that goes into producing them fluctuates like that. I also have a hard time believing my $40 holographic charizard card took 400 times the energy as my pidgy card.
I am interested in how the battery becomes AC to be distributed. It must be an impressive inverter to go along with the large battery.
Its always amazes me that so few people understand fundamental concepts about the energy that they use. The reporter probably just assumed that the battery is directly connected to the town grid.
new letter/phrase: hex-u means "www"
... but will it power an iPhone more than 2 hours?
a Dell laptop to that thing?
I'm not a lawyer, but I play one on the Internet. Blog
As you can see, the estimates vary widely, there's a lot of guesswork involved in making these estimates. Overall the renewables don't fare that badly, especially wind and hydroelectricity.
In case you were wondering, here's the CO2 emissions:
So yes, even with all the intensive energy requirements for renewables, they still are better than fossil fuels. The problems with widespread use of renewables are political (i.e. Republicans and conservatives don't like them), require intensive upfront capital costs, and infrastructural (the power grid is not designed to carry power where likely wind generation sites are).
Gentlemen! You can't fight in here, this is the war room!
Dwarf Fortress is, indeed, that epic.
There is something strange about illustrating your rigidly literal interpretation of my comment with some business about some game.
I didn't mean to say that the price would reflect that actual amount of energy used to produce the item, I meant that the cost of the energy used to produce the item is quite unlikely to exceed the price of the item (there are lots of easy exceptions, but a big industrial battery isn't really going to be one of them).
Nerd rage is the funniest rage.
Two things:
One:
Dollar cost is the easiest path to determine the energy cost of a project because it already takes in account all the inputs directly and indirectly (for example, the manpower costs include not only the transportation costs for that worker but also all the side-costs such as entertainment costs, housing costs and more of using that specific kind of worker - after all, if the pay was lower that the money the worker spends then he would - usually - not take that job).
Don't forget that indirect energy costs are extremelly difficult to calculate: for example, if a worker in the construction of that battery uses his/her bycicle to get to work instead of a car, then energy costs are lower, but if the money thus saved is spend in ways that consume more energy than that amount of gas has, then the energy costs are actually higher.
If you want to translate dollar costs to energy costs, the easiest way is probably to use the dollar-per-joule ration of money spent in direct energy sources in that area (mostly dollars spent in gas and electricity purchases per joule).
Two:
is actually the wrong question.
A closer to right question is: "How much energy did it take to make it versus the energy that is saved by having it?"
Even that is not the best possible question. Here's a better one:
"How much non-renewable energy did it take to make it and will take to maintain and decomission it versus the amount of non-renewable energy that is saved by having it during it's lifetime?"
If this battery allows this city to use renewable sources of energy (for example solar) instead of non-renewable ones, then this project might be worth it. In fact, it doesn't mater how much non-renewable energy it costs to make it (and maintain it and decomission it) as long as more non-renewable energy is saved by having it.
[Side note 1: This is why, for example, termal isolation in a house is almost always the most efficient way of improving one's energy profile: not because it does not consume lots of energy to make and deploy but because it saves a lot more energy than that over the course of it's lifetime. In fact, in sunny places usually the single most energy-efficient change to do is to have the outer walls of one's house painted white]
[Side note 2: This is also why in the long term nuclear might not be quite as great a source of energy as some people make it to be - it has very high decomissioning costs and current renewable energy capture technologies are still less mature by comparisson and will thus improve faster than nuclear over time (meaning that, later in the life-time of a nuclear reactor it will be saving less non-renewable energy than earlier). That said, at the moment it is one of the best options we have.]
Looks like the battery has somewhere around 30 MwH of storage (4 MW at 8 hours) and 1,500 or more cycles of lifespan (the latter according to Wikipedia). So the question you are asking is whether it costs more than 45 GwH of energy to make. That much energy is a bit over $4.5 million at $0.1 per KwH. So yes, it is possible that it could cost more energy to make than it discharges over its lifespan, depending on how much of the cost is energy-related.
That's not particularly relevant because this battery is used for reliability of service, which is a high value application. As another replier, Prof.Phreak mentioned, energy provided to maintain reliability has a much higher value than normal. A factor of ten higher is not unreasonable.
Finally, Rogerborg, I don't think much of energy-based accounting. First, as you note elsewhere, we don't know how much energy it takes to make this sodium-sulfur battery. The electricity provider could be lying about the cost or capabilities of the battery as well. But it is well known that a electricity provider can lose significant money from service disruption. Thus, my assertion that energy provided to maintain service can have a value far above that of the raw energy provided. That is why energy accounting doesn't work on its own.
It's the BIG OL' BAT'RY. You bunch of citified nerds. Have some respect for the Good-Old Boys.
Uhhhhh....if you are simply wanting to capture solar energy, wouldn't using molten salt be not only much cheaper but also more efficient?
After all it is certainly cheaper to have some mirrors focus the sun on a tank than to try to build truly efficient solar panels (last I heard the best were around 30% efficient and VERY expensive) and molten salt would at the same time solve the storage problem without the need for the expensive battery.
According to Scientific American we could have nearly 70% of our electricity needs met by solar by 2050 at a cost of 420 billion, using molten salt as part of the plan. Considering the amount of greenhouse gasses that would save by getting rid of coal it seems like a good deal to me. Add in subsidies to get folks into electric vehicles and we could finally stop using foreign oil, which lets be honest is well worth the price to keep from giving tankers full of money to militants like the Sauds.
ACs don't waste your time replying, your posts are never seen by me.
Just don't stick your tongue on it.
I'm not saying anything, I'm asking a question. It's one which is rarely asked
Bullshit. It's one that's asked *every fucking time* an article about renewable energy pops up on Slashdot.
Seriously.
Don't overestimate how brilliant you are. Believe it or not, you're not the only one to think about this issue. Not by a long shot.
The refurbishment cost will probably not be very hight. Sodium sulfur bateries get old because sulfur leaks into the sodium container (that was on that wikipedia article some time ago, maybe they removed because it is wrong), so all you'd need to do is to repurify the sodium.
Now, of course, since the calculations yeld a 90 years life time, something will surely happen earlier, and the battery will need some unforseen maintence.
Rethinking email
That unit is spelled "kWh", with small case "k" and "h", and no "r". The kilo prefix is always small case, and hour symbol is just "h". Upper case "K" is the abreviation of Kelvin (temperature unit). The prefixes biger than "k" are all upper case, like "M" (mega), "G" (giga), "T" (tera), but the smaler ones are all lower case, like "m" (mili), "n" (nano), "p" (pico).
Rethinking email
Oh, great! Research hard enough and you'll discover that the EROEI if this thing is below 1. Now, take some time for looking into other bateries, and you'll see that they have something in common, all of them have EROEI below 1.
Or you could think a little bit and see why your question is useless.
Rethinking email
you like tossing off batteries, don't you.
Roy was a good ol' Texas boy and was always braggin about how this is bigger in Texas, that's bigger in Texas; just Texas, Texas, Texas. One day his friend in New York state had it up to here with all this Texas bull, so he invited Roy up to New York, took him out to Niagara falls, and said, "I bet you don't have any falls this big in Texas now do you?" "No," replied Roy, "but we've got a plumber that can fix this leak in 5 minutes."
The problems with widespread use of renewables are political (i.e. Republicans and conservatives don't like them)
WOW!! Just, WOW!
Where do you people come up with such insanely stupid ideas. Republicans have no problem whatsoever with renewables. What they have a problem with is an overbearing government forcing feel good (but totally unworkable) ideas down our throats with government mandates. What they have problems with is ripping the heart out of a massive economy that is barely limping along as it is by mandating premature technology like was done with anti-lock brakes on vehicles.
Republicans love renewables as much as any other sane person when they make economic sense.
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
At 115 GJ fully charged, the TNT energy equivalent* of this NaS battery is 27.5 tons TNT.
* 4.184 GJ / ton TNT (source -- Wikipedia "TNT Equivalent")
The issue has nothing to do with politics and everything to do with money. If the numbers worked out there would be massive spending from the private sector into alternative energy. Instead we have massive govt spending to subsidize alternative energy source with no chance of a ROI.
Got Code?
There is a madly efficient thermal solar molten salt based solution for that no?
Lol... your first bit of data was from a blog called 'mdsolar' he took gov data and added his own multipliers to it seemingly at random to get those values. And the cite he gave for the figures he tweaked is down.
And the second block of data doesn't at all adress what you are talking about. Those are figures for full life cycle CO2 cost vs energy production. They don't take into account the variability of wind/solar and storage systems used to fix that or varied power grid systems AT ALL. It wasn't presented that way so I don't know how you came to that conclusion.
I love people posting data but you really need to be careful about sources and be sure about what specifically they are saying in the data.
How exactly does Sodium-Sulfur... A SALT... explode? Y'know, strong ionic bonds and all that.
This isn't like an electrolytic battery where you're separating two reactive substances, it's a big energy sink of uniformly mixed hot stuff.
Nobody worries about table salt (Sodium Chloride) exploding...
Sorry, I did miss the "maximum" word there. Generally I hate it when people use something's cost as a direct proxy for the amount of energy it took to produce it. A plumbing job doesn't cost a lot because it consumes a lot of energy, it costs a lot because people with the ability to plumb are (relatively) scarce. The pokemon cards thing was a joke.
RTFA. It's a Sodium/Sulfur SALT. The sodium is already bound into a compound.
You know, just like the hilariously-deadly Sodium/Chloride mix that you find in every kitchen.
And you're deliberate misinformation campaign about holding power! A whole generation of America's youth lost to scientific ignorance!
My Dad is a petrochemical engineer who specs equipment. He has told me they occasionally use large generators (over 1mw) that can go from not running to producing power, in a few cycles (less than one tenth of a second), using pneumatic start. I'm sure they are using some of the tricks listed in children posts, like staying preheated, and priming the exhaust and intake tracts.
Presidio is blazing hot more often than not, it often reports the highest temperature in the US.
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
I don't think this will ever be a viable way to store energy for load balancing. I think a better way to do that would be to store hydrogen and burn it as needed in a combined cycle plant. A combined cycle plant only costs about $0.50 per watt, while this sodium-sulfur battery costs $6.25 per watt. Using electrolysis with a combined cycle plant would give you about 50% efficiency, while the battery has 75%. Wind power costs $1.50 per watt to install and is available about 20% of the time. So if you want to produce one Watt of continuous power using wind and electrolysis it's going to cost $1.50 / .2 / .5 + $0.50 = $15.50, while doing it with wind and a battery costs $1.50 / .2 / .75 + $6.25 = $16.25.
There are other benefits to storing and burning hydrogen. The number one being storing more energy costs little extra (you just need a bigger hydrogen tank). Also, if your peak load is a lot higher than your average, it doesn't cost a lot extra to have a combined cycle generator that can supply your peak load. Finally, if you need to add extra energy to the combined cycle system you can buy gas or whatever and reform it into hydrogen (or just burn it directly).
I wonder how much heat is released in the charging and discharging of such a battery. Could we cure winter in Wisconsin or will the oceans simply rise another inch or two?
That last one will create a large number of small companies spread around the nation. More importantly, it can be used to power local areas. That will help smooth the demand vs. supply issue, as well as brown-outs. It would also allow us to deal nicely with issues about disasters. Finally, by moving to more of a energy storage approach, it makes a re-design of the grid so that they are smaller and then makes different kinds of electrical production easier.
I prefer the "u" in honour as it seems to be missing these days.
of an IDEA. Where does one begin to delve into this idea. What are the metrics for waste? Would intelligence be involved in a more efficient process. What are the metrics for process? Just random thoughts here.
Yeah, getting that sodium and sulfur is going to be SO expensive.
I prefer the "u" in honour as it seems to be missing these days.
Republicans drastically slashed funding for renewables research for decades, so I do think you protesteth too much on the basis of "premature technology". Their actions in this regard have been inexcusable.
Until recently, mandates have been extremely modest as a way of stimulating private sector research in the absence of direct government funding for research.
AFAIK the call to "make economic sense" is rhetoric that translates into "creates an obscene economic advantage for a handful of corporations over everyone else or at great cost to the environment". Renewables will never fit that bill.
http://en.wikipedia.org/wiki/Sodium-sulfur_battery
"A sodium-sulfur battery is a type of molten metal battery[1] constructed from sodium (Na) and sulfur (S)"
Why, is there a pool of molten lead around it?
No - this is a sodium-sulphur battery so there is a pool of molten sodium which acts as the anode: have a read here.
Nuclear (centrifuge): 18.1, 18.4, 14.5, 13.6 and 14.8
Vattenfall has demonstrated an EROEI of 93 on the Forsmark nuclear plant, by actually measuring their energy inputs, rather than inventing formulas.
http://nuclearinfo.net/Nuclearpower/WebHomeEnergyLifecycleOfNuclear_Power
Those who would give up liberty to obtain working drivers, deserve neither liberty nor working drivers.
not really. presume the factory had wind turbines (industrial sized, net gains) and/or other renewable forms of energy.
this battery could take more energy to build then those items could ever produce "out in the wild" for it to us and still make sense. this is a BATTERY. not a source of power. it only allows you to use existing transmission lines, and energy sources more effectively. And that can have great value whether it is a 'net positive' or not. Batteries solve portability and timing problems, not generation problems.
Rarely asked outside of Slashdot. Don't overestimate how insignificant we are. When's the last time you heard a policy maker asking it?
If you were blocking sigs, you wouldn't have to read this.
Rarely asked outside of Slashdot. Don't overestimate how insignificant we are. When's the last time you heard a policy maker asking it?
Is a "policy maker" gonna be reading Slashdot? No. So given the audience, your post isn't terribly insightful or even that original, as we've all heard that issue mentioned time and time (and time) again whenever an article about green tech pops up.
And this is ignoring the fact that, frankly, your supposition is simply wrong. Factoring manufacturing cost into total cost and energy efficiency is standard practice all over the damn place. Hell, any time someone wants to debunk green tech (solar is a favorite whipping boy), it's the first argument that's trotted out. Why do you think you can find numbers on total energy consumption for the manufacture of an electric car battery? Or a CFL bulb?
So, I repeat, don't overestimate how brilliant you are. The last thing we need around here is another know-it-all computer nerd who thinks he can debunk science and technologies from his computer chair, armed only with the trickle of information available in a Slashdot summary and his limited knowledge gleaned from pop-sci articles, bloggers, and wikipedia articles.