East Texas Getting Compressed Air Energy Storage Plant 248
First time accepted submitter transporter_ii writes "A compressed air energy storage (CAES) plant was first built in Germany in 1978, but East Texas will be the site of one of the world's first modern CAES plants. How does it work? A CAES power generation facility uses electric motor-driven compressors (generated by natural gas generators) to inject air into an underground storage cavern and later releases the compressed air to turn turbines and generate electricity back onto the grid, according to the plants owner. The location near Palestine, Texas was selected because of its large salt dome, which will be used to store the compressed air. The plant is estimated to cost $350 million-plus, and will create about 20 to 25 permanent jobs."
Efficiency? (Score:5, Interesting)
Anybody knows how efficient is that? As compared with storage in water reservoirs for example?
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Re:Efficiency? (Score:5, Informative)
Compressed air is probably 75 percent of that.
Depends how adiabatic the whole system can be made. Needs to be terribly well insulated to store the heat of compression. Dieseling the lube oil inside the compressor pistons is probably the limiting temp on the hot end.
Water storage loss is very low, evap and leakage. Compressed air heats up and you need that heat to stay in the tank or you lose the energy.
Also your example of 85% in and 90% out seems a bit messed up since .85*.90 is about 76.5% which compares favorably to your pneumatic air storage system.
Non-adiabatic systems like pneumatic control systems used in factories etc are ridiculously inefficient. You end up with a 10 HP compressor output an effective 1/4 HP of "machine". No one is seriously suggesting non-adiabatic systems, like house or car or factory size.
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The only way I see to get around this is to liquify the air and pour it in, similar to how LNG and LP gas is processed for storage. I doubt the liquid would last very long, but if this is done, there will be significantly more energy able to be stored because of both the temperature and pressure difference, as well as the phase change which happens at 330 bars/5000 psi at 68 degrees (F).
Re:Efficiency? (Score:4, Insightful)
With a huge (call it infinite) reservoir, you can approach adiabatic. Air heats on the way in, but also cools on the way out. Dirt is a pretty good thermal insulator. If the caverns extend down to geo-thermal areas, you might even get some geo-thermal heating boost.
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Can you explain how that is a net loss, if all your power generation relies upon is the PSI? I do understand that air heats when compressed. But it also chills when decompressed, causing the heat that it released earlier to be sucked back in to the system. ...Is it perhaps that when the heat of compression dissipates out of the system, the PSI has been reduced?
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Also your example of 85% in and 90% out seems a bit messed up since .85*.90 is about 76.5% which compares favorably to your pneumatic air storage system.
Pumped-storage hydroelectricity [wikipedia.org] "reported energy efficiency varies in practice between 70% and 80%, with some claiming up to 87%" The book Sustainable energy without the hot air suggests that 90% efficiency [cam.ac.uk] is probably achievable with some small technology increases.
Compressed air energy storage [wikipedia.org] "The theoretical efficiency of adiabatic storage approaches 100% with perfect insulation, but in practice round trip efficiency is expected to be 70%."
well if you ask me... (Score:3, Funny)
Good luck (Score:2)
This cannot possibly be efficient (Score:5, Informative)
When your compress air it heats up, increasing the pressure and making it harder to compress more air.
After it's been in the ground for a while it cools back down to ambient temperatures.
Then when you're extracting it the air is expanding which makes it cool down and reduces the pressure, therefore reducing the practical energy you can get out of it.
This is basic stuff you learn in Chemistry I.
Re:This cannot possibly be efficient (Score:5, Informative)
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If only there was some way Texas could heat up all that air. It's too bad it's such a cold and cloudy environment all year long.
The best that they can ever hope for is the air at the temperature coming out of the ground.
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When you store natural gas in salt domes, the energy isn't in the pressure, it's in the gas itself. You don't care if it retains pressure as long as you can store more gas in there. In fact, you're prefer lower pressure in general, it's easier to work with.
The volume doesn't matter except to improve volume to surface area (radiative/conductive area) ratio. Each bite of air heats up the same amount during compression whether you then dump it into a big cavity or a small one.
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Perhaps at the exit, run the pipes through solar collectors. Using solar heat would be a cheap way to drive up efficiency.
350 million-plus *what*? (Score:5, Insightful)
Square feet?
Cubic yards?
Kilowatt-hours?
Bottles of Lone Star BBQ Sauce?
Ping-pong balls?
Dollars?
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Artichokes per hedgehog second, I guessing.
Sounds reasonable.
I've some hedgehogs living in the bushes under my balcony and a Chairman Mao 100th Birthday commemorative pocket watch with a working second hand. Not sure if you can grow artichokes round here or not, though.
Jackpot! (Score:2)
Someone must have patents on that technology. Will East Texas continue to be so patent friendly when they are going to be receiving the sharp end of the stick?
Why not use Solar to compress the air? (Score:3)
Generating the energy to fill the storage with compressed air by burning Natural Gas (NG) seems stupid to me. It is more efficient to just leave the energy stored as NG. Converting that to compressed air and then again to electricity adds a middle step that adds inefficiency.
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I don't know why solar isn't being used, but on the burning of natural gas, it sounds like the purpose of a compressed air reservoir is that it can generate large amounts of power on demand, so it acts like a large battery that helps to ease peak demand spikes. From the article:
According to Apex’ website, compressed air energy storage (CAES) is unique in its ability to efficiently store and redeploy energy on a large scale in order to provide low-cost energy and enhance grid reliability.
Makes it soun
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I agree with you. Heck even if you're going to compress something, compress the natural gas!
All I can think is there is a limitation on how rapidly (or slowly) they can burn the natural gas and turn it into electricity. Otherwise, just keep the natural gas around until you need the energy and burn it then.
Why if there's a limit on how fast you can burn the natural gas there wouldn't be one on free-wheeling it into a turbine too I have no idea.
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Watch out for the Thundercats prowling around...
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Gas is burned to produce electricity (at efficiencies of no more than about 20-30%),
More like 60% for modern CCGTs. Even older ones should be above 50%, if they haven't been scrapped due to low efficiency.
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"In the UK, we have three pumped storage facilities of about 50MW each (or thereabouts)."
The Dinorwig pumped storage system in Wales has 1800MW of generating capacity which it can deliver for at least 30 minutes full load; I believe its total storage capacity is about a GWhr or so. Cruachan in the Highlands is the other major pumped-storage plant in the UK, capable of supplying 440MW on 30 seconds notice but it can sustain that level for over 20 hours. It is always kept at a minimum 12-hour level as a "bl
it will be either a cool energy storage medium (Score:3)
or the most unique way to asplode a salt dome yet invented
This is why we need a supergrid. (Score:2)
The first CAES plant, a 290 megawatt facility, was built in Huntorf, Germany in 1978.
The Bethel Energy Center is slated to be a 317 megawatt facility which is about one-quarter of the size of a gas-powered plant near Richland Chambers in Freestone County, according to Farley.
So a few decades later, we are going to be the cutting edge in building something with effectively the same operational capacity as the original? Keep in mind these things are just giant batteries that use air pressure, and I'm assuming the same electric motors that pump air in will extract energy when the air comes back out, with a ~80-90% efficiency either way.
We spending a third of a billion dollars to push air around like they did in the 70's.
Recovering the energy (Score:2)
What a fucking useless waste (Score:2, Insightful)
Going from natural gas, to electricity, to compressed air?
Just go from CNG to elec or convert plants to run on CNG.
What the fuck, Texas Engineers?
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i'm confused (Score:3)
The advantage to CAES energy storage seems to be in allowing the energy producer to maintain a lower peak capacity. During times of low demand he produces a surplus of energy, some portion of is stored as compressed air. During times of high demand this stored energy is released and used to augment what his production apparatus can natively provide.
That's all well and good. What confuses me is that this thing in Texas is going to be powered by natural gas. I had thought one of the main advantage of natural gas for electricity product was its ability to power gas turbines, which can be "spun up" (or down) fairly quickly in order to satisfy periods of high demand. How does natural gas powered CAES storage compare to simply having a larger installation of gas turbines, some portion of which will only be selectively spun up during peak demand?
wait what? (Score:2)
your using natural gas to create electricity, to create compressed air, which is then stored then used at a later date to produce electricity... why not just not burn the gas in the first place and save that to create electricity?
Be careful with that salt dome.. (Score:2)
Make sure it doesn't swallow an entire lake:
http://en.wikipedia.org/wiki/Lake_Peigneur [wikipedia.org]
Wouldn't... (Score:2)
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It's bad for crab people, but I don't think they'll be able to use this one. The whole environmentalist movement was conceived by the underground crab people as a way to destroy humanity's industrial capabilities and thereby facilitate the crab people's takeover of the surface world. So, ironically, the environmentalists can't bring up the thread to subterranean crab people as this would mean admitting to existence of the conspiracy.
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As the summary notes (but the article doesn't seem to mention), the air is first compressed by natural gas-driven motors. That means such wonderful natgas procurement methods like fracking are ultimately involved.
I hope, at least, that using CAES is more efficient than just burning the natgas and twirling the turbines with that. (I doubt that but I'm no energy expert.)
Re:I wonder (Score:5, Informative)
I hope, at least, that using CAES is more efficient than just burning the natgas and twirling the turbines with that. (I doubt that but I'm no energy expert.)
It can be more efficient if wasted power generated is less, because power demand is highly variable. Burning straight up natgas may lead to waste, if not all the power generated is required. With CAES, all the output can be stored until needed, as long as there are no "leaks" in the underground cavern, and the rate of pressure loss isn't too high.
With CAES, the power generation output can possibly be more easily reduced, during off-peak hours, to match the demand, with less loss in efficiency, and without having to shutdown/fire up a certain number of natgas generators based on demand.
Re:I wonder (Score:5, Informative)
I just want to add something that might be escaping some people.
Most natural gas generators on the scale of a public utility use a turbine engine which means that it's efficiency concerning getting work from the fuel used is pretty much in a narrow spot close to peak production. If you wind it down to generate less electricity it becomes less efficient and degrades the engine components faster so it's avoided. If you keep it in it's peak range but turn the generation down, you are being almost as wasteful as if the machine was producing full bore all the time whether it was needed or not.
This is even true for traditional internal combustion engines like in your car or motorcycles where it is geared so that your cruising range is between a certain RPM in order to take advantage of it. Outside that range is a little less efficient but isn't as pronounced as it is when you are dealing with an engine producing thousands of horsepower to drive gigantic generators.
What this compressed air storage does is allow the generation to be controlled by something that can be turned up or down easily as demand increases or decreases (compresses air) and the natural gas portion of it operates in the peak efficiency range of converting fuel to useful work when it is running.
how much of this translates into savings or overall efficiency improvements is something I don't know, But it seems to be enough (on paper at least) to throw millions of dollars at.
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It makes no sense. Natural gas turbines are dirt cheap compared to other forms of power generation and natural gas is way too expensive to waste on compressing air. Gas turbines are also quite small, the world's largest turbine seems to be 340MW. Since they start up and shut down rapidly (tens of minutes), they are easy to regulate: you just turn the off when they aren't needed.
Re:I wonder (Score:5, Informative)
The bit about natural gas in the submission is simply wrong. There happens to be a natural gas power plant somewhere nearby, but the two facilities have nothing in common. It is unlikely that the storage facility will be storing power while the natural gas power plant is providing it.
Re:I wonder (Score:5, Informative)
Someone mod this up. You'd have to be retarded to use natural-gas-generated electricity to operate an electric compressed air storage plant. The submitter just made that up.
Texas has a relatively de-regulated electric grid with a lot of wind capacity. Prices fluctuate wildly. This facility will use renwable wind and solar energy to compress air at times when it is cheap. Then, at times when electricity is expensive, the air will be used to operate a natural gas turbine and generate electricity.
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It's a large battery for unstable renewable energy sources. Got it.
Well, that solves the energy storage problem for renewables, at least for localities that have suitable geological structures. I'm also going to assume that the efficiency for these wind turbines is top notch, and losses due to transmission are minimal.
When I first read the article & summary, I thought I was going to have a stroke. For a brief moment, I pictured them burning natural gas to store compressed air in the cavern. I wondered h
Don't think digitally (Score:2)
Also tens of minutes to fire up is a long time when something has unexpectedly gone offline. Hydro and pump storage (plus compressed
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That said, I see this as something similar to electric vehicles. Sure the EV's are initially run on coal fired plants, but now that the consumption is in electric you can switch the plant and make them much much greener.
Step 1 of a multi-step process.
Re:I wonder (Score:5, Insightful)
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I can see this having a better future with renewable energy like solar, so that lights that are on at night can be powered from grid-supplied solar energy or wind energy when there is no wind. For solar, it would have to
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Yes, I don't quite understand this from an energy efficiency point of view. They're using natural gas to run compressors to store compressed air that they can later release through generator turbines to generate electricity. It seems like the infrastructure costs for the natural gas-powered compressors and the generator turbines to generate power from the compressed air shouldn't be less than it would cost to just build a bunch of natural gas-powered generators.
I could understand it if they were using it to
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what the environmentalists will use for an excuse for why this is evil...
Natural gas is being used to power the compressors, instead of power from intermittent wind or solar (at least according the summary, TFA doesn't say that).
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Re:I wonder (Score:5, Informative)
Oh, uninformed twats all up in this thread; surprise, surprise.... (chiefly referring to submitter and GP)
First some links (as opposed to URLs as text -- this is 2012, learn HTML or GTFO):
EPA application you didn't link. [epa.gov] A good read that should have been in TFS.
The company building it. [apexcaes.com]
The gear to be used. [dresser-rand.com]
Okay, the submitter clearly got confused, but I think differently. Possibly from this sentence of the EPA application:
A natural gas fired reciprocating engine will power an emergency electric generator rated at 740 ekW, necessary to support starting the plant when power from the grid is unavailable (“black start”).
The other possibility is because it's a natgas-fueled hybrid CAES rig, which concept is apparently very difficult for a certain class of mushbrain to grasp.
This plant uses only electricity from the grid to compress air. Could well be from natgas (which is damn cheap these days, and less CO2 than oil or coal), but if so it'll probably be a modern combined-cycle plant with high efficiency. Could also be nuclear, hydro, wind, or coal.
It DOES, however, use natgas to run -- rather than simply blowing compressed air down to atmospheric in a turbine, they use the stored compressed air in a Brayton cycle. A conventional gas turbine exhibits low load range (typically can't run less than 50% of maximum power), because the compressor is designed for specific conditions; throttle it back, and you lose efficiency rapidly, and eventually it stops working completely.. With a hybrid CAES plant, though, the gas is pre-compressed, so you just add heat (burn natgas) and expand w/ reheat. This allows scaling to very low power output. (In this particular case, the very high storage pressure (1900~2830 psi) actually means they can put another turbine before combustion, blowing the air down to around 800 psi.)
Best i can tell is that they buy electricity during non-peak, and use that to compress the air so that it can be released against to drive the turbines during peak. Almost as if they are acting as electricity speculators (buy low, sell high).
More like cross-border arbitrage than speculation IMO; even though peak and off-peak pricing aren't set simultaneously, they both usually move slowly compared to the diurnal alternation of the two. So to me, rather than considering it a single market with wild periodic swings, it's useful to treat it as 2 (or many) concurrent markets, of which you can only trade in one at any given time.
Re:I wonder (Score:4, Informative)
Not really speculators. Electric utilities have several rates it costs them for the power they generate or obtain and sell to the consumer. They are classified as base, peak, and overages of either.
They determine their base usage which can be done relatively easily and purchase or generate that much plus 10 or 15 % (I forget what the demand surplus by law was last time I checked but this is needed at all times to avoid brownouts and so on). They only purchase or produce enough energy to supply this needed amount the majority of the time. Excess energy is either sold to other utilities or not purchased. This is the cheapest rate by far because it can be purchased by long term contracts and the generation facility can be running at max performance at all times.
The next rate is the peak usages which is similar to the base but only applies during the peak times electricity will be used. It's a bit more expensive because peak times are generally within hours of each other all across the nation. This means that an electric producer somewhere has to have generating capacity on standby for these times and not in use for others. Of course if you have generating capacity and the investment needed to procure it, maintain it, and transmit it, you would do it all the time to get the benefits of economic of scale (producing 1000 units for sale with the same devices instead of 100 units). But because this is only needed for a relatively short period of time, the generation costs lost by not being needed the other times is recaptured in the increased pricing for the peak costs. This is also subject to long term planning so long term contracts can secure cheaper prices then the third type of energy, the overage type.
The overage type of energy a utility needs to purchase is all amounts of energy in excess of the base or peak estimates not covered by an existing contract and is purchased as needed when needed. This is the most expensive because someone has invested in a generation facility that doesn't make much money unless utilities plan poorly or something happens outside their control or expectations. This down time is also recaptured in the pricing. An example of when this is needed is when there is a heat wave and not only is everyone running their Air conditioners set on max, but they are turning on fans and everything else they can think of to keep cool. Perhaps a sale on plug in electric cars added to the load for a specific utility in a short period of time on top of that and everyone plugs in when they get home from their 9-5 job. Or there is a rash of burglaries and everyone is increasing their outside lighting and leaving more lights on at night in order to avoid being a victim. Whether the utility is on base or peak at the time, the amount of excess or overage capacity that needs to be available is purchased as needed and at the highest prices they have to pay for electricity to sell to their consumers.
All that is figured into your rates when you get a bill and isn't really obvious. The term overage might be the wrong term to use (I'm thinking it might be something else but am too lazy to look it up). Some utilities separate peak rates from base rates and charge more for peak to give you an option of trimming your usage during the peak. But buying on base rates and reselling on peak or even overage rates is sort of how the entire electrical utility industry operates except energy storage techniques haven't traditionally made it practical. It is the same concept except that the source fuel is separate by a conversion factor (natural gas or coal converted to electricity to be stored as compressed air to be converted back to electricity) instead of being converted to electricity only once.
This type of pricing to the utility is also something that makes the usage of solar and wind power difficult to use. Maybe if this project proves useful and profitable, alternative energy could use compressed air storage to store it's production and sell in the same ways to get around the problems of compet
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what the environmentalists will use for an excuse for why this is evil... maybe compressed air is bad for subterranean cave bats?
I wonder what impurities the compressed air will pick up while its stored.
Re:Do they gain energy due to seasons? (Score:5, Informative)
Likely not...earth is not a really good conductor of heat and the air temperature in caves tends to vary only slightly over the year.
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However, what does is that compression heats the air, while the ground will take it from it. That is where you lose your efficiency.
When the ground takes sufficient heat from the air, the pressure will drop, causing a reduction in the work required to compress more air, and the pressure drop also makes the air less thermally conductive, so this is a self-correcting situation.
The air they are pumping in will probably be hot air.
The primary efficiency loss will likely be lost waste heat from the nat
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The air they are pumping in will probably be hot air.
...and the air they get back will be cold air, hence energy loss.
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East Texas: infinite demand for cool air 9 months of the year.
Re:20 perm jobs? (Score:4, Informative)
More importantly, I don't get why anyone would advertise that 350M is being spent to create 20 "permanent" positions. That's 17.5M per fulltime job!
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It's not a job creation scheme, it's supposed to make money for some power company. The jobs are being mentioned to make the locals feel better about having this thing nearby.
Re:20 perm jobs? (Score:5, Interesting)
It's not a job creation scheme, it's supposed to make money for some power company. The jobs are being mentioned to make the locals feel better about having this thing nearby.
Yeah, because what could possibly go wrong with a bunch of high-pressure air pumped into an underground cavern?
Think of the jobs... Forget Lake Peigneur [wikipedia.org].
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I don't think it's fair to compare this scheme to complete idiots just because salt is involved.
Re:20 perm jobs? (Score:5, Insightful)
With no lake above the salt mine any new oil wells would just punch a hole in the ceiling of the mine that would have to be patched. While their is a small creek that passes above the retired salt mine, I highly doubt anyone would choose to drill in the middle of a creek when they could move 100 meters in almost any direction and have an easier time of it.
In addition, it isn't like they are pumping natural gas or other volatile chemicals that could cause a problem via explosion through a puncture- it is air, and at 60 to 70 bar is unlikely to cause any problems when there is almost 4000 feet of rock on top of it.
That said, the giant swirly that was Lake Peigneur was epic.
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I'm just thinking along the lines of 70 bar (1000psi), working its way into places that people didn't know connected to the salt mine, say places underneath big sources of water...
All pipelines leak, even the ones that carry volatiles like natural gas - it's just the economics of lost product cost vs maintenance cost. Can't imagine anyone in that industry getting too worked up about a little leaking air. And, judging by the Lake Peigneur training and effective evacuation, I'm guessing everybody in charge
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One of our patients works at a underground CNG storage field, the pressure used is 15,000 psi. The school for operating the compressors is a full two week long. We have numerous CNG storage fields, several salt mines and numerous brine wells, not to mention oil and gas wells in our area. This is old proven technology there should be no surprises other than human error.
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More importantly, I don't get why anyone would advertise that 350M is being spent to create 20 "permanent" positions. That's 17.5M per fulltime job!
... for how many years, and does that 350M have any return? If those permanent positions are there for the next 50 years, and the plant starts making 50M per year in energy sales, then it's a pretty sweet deal.
Not that it necessarily will, but in your rush to compare two numbers, you missed the fact that there are several more involved.
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I just realized that ultimately any municipal services provider is fully funded by the taxpayer.
Oh my god. That means Walmart is also taxpayer funded since taxpayers buy all their products! We must put an end to this!
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Obviously.
Nobody wants to live near this thing. In the beginning this will mean protests, which will create jobs in the DIY market for all the picket signs. This will also create jobs in the riot control business and hospitals. In the end, people will just move. Moving companies will be able to create hundreds of jobs. And those people will have to move to newly build houses, which is several thousand more jobs. The old houses will have to be destroyed, which creates a multitude of jobs in the demolition in
Re:20 perm jobs? (Score:5, Insightful)
This isn't a government make-work program. It's a project intended to serve an actual purpose, with the creation of permanent jobs as a nice side effect. The 'goodness' and cost-effectiveness of the job will be whether it reduces the ratepayer's bills, and/or increases utility profits (not sure of the regulatory structure out there), and/or increases the reliability of the grid.
If it could do those things and employ zero people, it would still be a good expenditure.
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I'm pretty damned sure it'll be:
a) No way in hell.
b) Goes without saying
c) Highly unlikely.
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Re:20 perm jobs? (Score:4, Insightful)
Dividing the cost of the construction by the number of employees doesn't give you the cost of the jobs. Or any meaningful information, for that matter.
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In this context, "permanent job" just means it's not a job that only lasts as long as it takes to build the thing, but continues after construction.
Maybe a better term would be "ongoing job" but since most everyone knows what is meant by "permanent job", I don't think there's a desperate need to change it.
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there's no such thing as a perm job in the US
Comprehension tip: The job is permanent, not the employee.
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Well, while you are at it (Score:2)
Well, while you are at it, "generated by natural gas generators," should have been: natural-gas-powered generators or generators powered by natural gas.
Didn't really think it would get published.
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I'm thinking if this system accidentally vents, it'll be the biggest fart in history.
Wait till some PHB builds a system like this in coal fire country. Centralia PA.
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Actually, as long as the ground is going to be on fire for a few hundred years and there's nothing you can do to stop it, might as well find a way to extract the energy. Has anyone looked into extracting geothermal energy from underground coal fires?
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I don't know enough about to to know if it's a good idea or
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It looks like they're saying the grid powers the motor, and the majority of the local generation is NG. Powering the compressors with locally-generated electricity would just be a fantastically stupid power plant.
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Not necessarily, there may be money to be made if this thing guzzles cheap power all night so it can ejaculate expensive power during peak air-con hours.
If your power system is based on natural gas, there won't be any cheap power at night. Natural gas power plants do not need to run at a loss through the night, unlike most other forms of power generation.
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"It would make more sense to me to store energy from the many Wind Farms, which are horribly inefficient (and costly) in a grid system."
I agree. Up here in the Northwest, we have a ton of wind farms that are intentionally idled when our Cascades reservoirs are full and they have to dump water--they don't want to waste the energy stored in the form of water but are perfectly willing to power-down huge wind farms that are producing electricity at the same time. This technology would solve that problem for bot
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Compressed air storage is fairly old hat. It is horribly inefficient and you can only economically save up for a few days, unlike the way hydro is able to save power up for months.
Wind power in temperate climates luckily works well with hydro: Wind produces most power in winter where hydro is at risk of running dry, and less in summer when reservoirs are full. If you have any hydro at all, it is almost certainly not worth it to do compressed air storage.
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Are you trolling? What is 'inefficient' about a generator whose fuel is free, compared to (say) sub-50% thermal efficiency from burning coal (and dumping various toxic and radioactive nasties on your neighbours)?
Rgds
Damon
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Simply isn't how it works in most grids: it's not the wind's fault if it's managed badly.
So "notoriously inefficient and unreliable" is simply inflammatory and incorrect.
No generator is completely free nor perfectly reliable: nukes trip out without warning causing blackouts for example, as do coal and gas plants.
Rgds
Damon
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The natural gas is for reheating the air before it decompresses. Otherwise they will be blowing near-liquid air through the turbine blades. Not a good idea.
See Diabatic storage.
"Upon removal from storage, the air must be re-heated prior to expansion in the turbine to power a generator which can be accomplished with a natural gas fired burner for utility grade storage "
http://en.wikipedia.org/wiki/Compressed_air_energy_storage [wikipedia.org]
Re:CASE or CAES? (Score:5, Funny)
CASE = CAES Acronym Spelling Error
Re:CASE or CAES? (Score:4, Funny)
Re:CASE or CAES? (Score:4, Funny)
Iknowrite?
For a second there, I thought they had a winner, after all, they have a large amount of compressed gas already milking idiotic patents in the region... Storing the energy from all the East Texas patent lawyers might prove a great way to harvest alternative energy sources and reduce corporate trolldom!
Sadly, I fail to see how these efforts won't be thwarted by the same patent lawyers.
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What is the advantage?
It is to store the power: currently, there are no batteries capable of doing that. A major problem with the power generated from solar panels and any kind of turbine (wind, for example) is that it will be lost if you don't use it on the same turn.
I am not sure if that's what you asked, because your point may also be "why they are burning the natural gas to run this power storage facility, since power is already stored in the gas and they can burn it when they need it". In that case, it could be a matter of
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What is the advantage? Why can't they just burn the natrual gas to make the electricity instead of turning a compressor to compress gas to turn a turbine
Latency and cost.
A 1 MW air turbine is cheaper than a 1 MW natgas turbine, but depressingly not much cheaper. Temps are lower so you can use cheaper alloys / spin it faster and you don't have to deal with igniters and gas injection. I'm sure it ends up being about the same cost in the end as just storing natgas in the tank and burning it.
The latency is a big deal. I would imagine there is backlash in the gearing that limits reaction speed to "fraction of a second but probably a lot longer than half a 60
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