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East Texas Getting Compressed Air Energy Storage Plant
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."
"...according to the plants owner."
What does a guy who owns many plants know about compressed air storage power generation?
Anybody knows how efficient is that? As compared with storage in water reservoirs for example?
Rome taught me patience and assiduous application to detail. Virtues which temper the boldness of great, general views.
Sounds like a lot of hot air.
So does the ground temperature change enough from one season to the next to give them a net increase in energy from winter to summer? If they're compressing air during the winter, when power consumption is lowest and renewable production (specifically wind) is highest, and decompressing during the summer, when it's the opposite, they could get a net increase in stored energy because the ground heats up, causing an increase in air pressure. That would be nice.
They probably mean a job that isn't temporary (non-construction work) with no definite end date. Presumably the life span of this plant may exceed that of a persons lifetime employment (40 years).
Hope it works. There are lots of salt domes on the Gulf Coastal Plain.
It is Texas. One more big fart won't even be noticed until he runs for president.
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.
>> The plant is estimated at 350 million-plus
Units are?
My belief is that America's (actually, the west's) real issue is that we have a lack of storage. The best thing is to put forward a time-limited subsidy, say 5 years, that starts high and drops over a 5 year period. It should be for all storage that is manufactured locally, and not allowed to be exported until subsidies end. More importantly, it should NOT be limited to what some politician picks.
I prefer the "u" in honour as it seems to be missing these days.
I wonder what a full rupture will look like...
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.
Square feet?
Cubic yards?
Kilowatt-hours?
Bottles of Lone Star BBQ Sauce?
Ping-pong balls?
Dollars?
Il n'y a pas de Planet B.
Seems like it would be cheaper to just store the natural gas in the cavern... =S
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.)
You can hold down the "B" button for continuous firing.
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).
Since (I think) gas fired generators are fairly efficent, and can quickly respond to demand changes on the grid, why would one wish to lose the energy required to perform the compression?
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.
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!
Every expression is true, for a given value of 'true'
Why not use solar or wind to run the compressors?
The storage would negate solar and winds biggest drawbacks. No solar at night. Not always windy.
Using natural gas to drive compressors instead of just making electricity just seems like a waste. Natural gas generator plants can already be brought online in seconds and don't NEED storage....
That's my interpretation, too. The job is permanent; the person filling it not so much. If the plant's expected minimum staff is 20, that means that at all times through the plant's life, 20 people will be employed (ideally). Of course, more may be brought on for construction, upgrades, or maintenance, but those wouldn't be considered permanent.
You do not have a moral or legal right to do absolutely anything you want.
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.
Doctors destroy health, lawyers destroy justice, universities destroy knowledge, religion destroys spirituality
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?
We don't see the world as it is, we see it as we are.
-- Anais Nin
No, that would be the CO2 from a lake in Africa that earned that. Many animals and ppl died.
I prefer the "u" in honour as it seems to be missing these days.
A compressed air energy storage (CAES) plant... ...world's first modern CASE plants.
Oops - CAES has just become CASE.
A CAES power generation facility uses electric motor-driven compressors (generated by natural gas generators)
I think you mean "powered."
according to the plants owner.
Apostrophe!
The plant is estimated at 350 million-plus
350 million plus what?
systemd is Roko's Basilisk.
This sounds like an interesting energy storage system. Storage is exactly what is needed to make solar energy generation practical for use when the sun is not shining at night. That idea gets me excited.
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.
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.
You are welcome on my lawn.
CASE = CAES Acronym Spelling Error
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.
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.
That is how I prefer to think of it
perm from the viewpoint of the position not the person
PS you only get to complain about getting fired if you have never quit.... fair is fair
Om the way home from LinuxCon 2000, we stopped at Taco Bell to get some grub and take a shit. Keep in mind this is after a week of pizza, beer, jolt, doritos, cheetos, etc. Anyhow, Cowboy Neil is shoving tacos in his face so fast I'm not sure why his fingers haven't been bitten off. Then he stops. Dead cold, no motion except the sweat trickling down his face. We hear a rumble and he gets up and runs (or waddles at a high speed) towards the bathroom. We're cracking jokes about it but after 15 minutes, he's still not out. I get up for a piss and when I enter the bathroom, the stench made my eyes water. I almost threw up then and there. I didn't get a good luck, but I think there was shit everywhere. Anyhow, nobody died but two people were taken to the emergency room. To this day, Cowboy Neil can use the Taco Bell drive through but isn't permitted inside.
or the most unique way to asplode a salt dome yet invented
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
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.
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 money: the gas is available now, and it is cheap. So maybe they want to store that energy as fast and cheap as possible, and sell it as pricey as possible later. I don't know.
The three laws of thermodynamics:(1) You can't win. (2) You can't break even. (3) You can't even quit.
Slahshdot editors proof read posts? Unpossible.
Note: CAES != CASE. Oops! Samzenpus, please try harder in future.
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.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Could be the submitter got derailed by the mentioning of a nearby gas power plant in the article.
Ok, some quick searching found this: http://www.epa.gov/region6/6pd/air/pd-r/ghg/apex-bethel-app.pdf
Hrmf, i see no wind or solar in their setup. 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).
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 hz cycle". So if a gust front simultaneously hits every windmill in TX the valve can slam shut, or if a miles long alien space ship instantly warps in and shades all the solar panels in TX the air valve can slam open.
Natgas turbines react a bit slower. Fast, but not as fast as an air valve.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
It's not (really) about the jobs. It's about spending public money to make some wealthy people that much wealthier. Yes, I said public money. If history is any indicator (an it usually is) the expense of providing the additional municipal services this project will require will fall to the taxpayers and not to the plant owners. In fact, those owners will probably get a tax break for creating all those jobs. You don't really buy all that bullshit about the payback from giving government handouts to "job creators", do you?
at least if the bubble bursts, there'll be no question about whether or not it happened!
Honestly though, wouldn't it make millions of times more sense to use tidal energy from the gulf, or wind-farm energy or solar energy? The biggest selling point of natural gas is on-demand power, the biggest detraction of wind and sun power (and wave power) is that its availability is not consistent over short periods of time. Some days it rains, some days the winds are calm, some days the seas are flat... just the place you need to store energy for on-demand return.
Something about this just doesn't add up. I suppose though, storing energy could be a good hedge against fluctuations in energy costs, but who really does that benefit? If that's the main (or only) purpose of building this thing, the general public doesn't benefit at all, only the guys who own the thing.
They forgot to Whitehouse-ify the numbers, clearly this is going to create over 10,000 jobs!
Forget about natural gas. They're not burning natural gas, nor are they generating any electricity. They are only storage. They are proposing a 317MW storage facility, with no specified storage capacity, that is one county away from an existing ~1.2GW natural gas power plant.
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.
I did some looking around at this about a year ago and it turns out that the compressed air expands and therefore cools so much that unless you preheat it everything will ice up. In fact the recovery unit is typically a NG turbine. Exhaust heat from the turbine preheats the compressed air which is then mixed with NG and fed into the turbine to get boosted combustion. Much more efficient than compressed air alone.
They are not going to burn natural gas (at least not in their turbines) to store the air. Average wholesale prices in Texas are less than $80 per MWH, peak is $3000 per MWH during summer months, over-night gets close to $0 in areas with lots of wind turbines and constrained transmission lines. They will buy when prices are cheap overnight (nuclear plants don't like to slow down, wind mills max out in most of Texas, harder to spin up and down coal plants) and sell during peak loads during the day. Unclear to me what is the plant capacity to work out a $/day formula.
This obviously wasn't open bidding. I would have supplied 20 full-time positions for just $16M per job.
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.
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?
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
uh oh, somebody's being case sensitive
Escher was the first MC and Giger invented the HR department.
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.
Alcohol, Tobacco and Firearms should be the name of a store, not a government agency.
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.
There's no -1 for "I don't get it."
disclaimer: I'm a huge fan of texans. your government, not really.
this is a state that fails to recognize things like the need for comprehensive medical care and climate change science. they push each year to have evolution redacted from the textbooks and think assembling as elected leaders to pray for rain will somehow solve this states perpetual immolation and drought problem. Texas legislature presides over the largest teen pregnancy rate in the nation yet insists abstinence only is a perfectly reasonable approach to the situation.
what marks this as pork is the fact that texas has somehow found a way to eschew its unbearable aversion to science and technology for just this time in the pursuit of energy that is not fossil fuel based, and creates a staggaring 20 jobs in a county that publishes no statistic on its unemployment.
Good people go to bed earlier.
I think any practical implementations of alternative energy sources is a good thing even if it works out to not be cost efficient or give the power it promised. Its still steps in the right direction it seems regardless of outcome. The handful of extra jobs part is useless side bits of information that I'd rather not have had. I would imagine this would have taken provided more than 20 jobs and hearing that number is actually a letdown. Good luck and hope it works out better than expected!
http://interserver.net/
I hope that contraption is patented and that they pay royalties on every kwh that comes out.
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.
I hope it wastes less energy, but converting energy from one form to another always loses energy and this sems to add two conversions to the current system, so I don't know how much more efficiency can be expected. Did anyone see figures on efficiency in the article? I only skimmed it.
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 be at least equal to something like heating salt during the day to give the energy back through steam powered turbines at night, so again some numbers on efficiency would be useful
Good luck sometimes arrives disguised as bad
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.
Finally! A year of moderation! Ready for 2019?
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?
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.
Finally! A year of moderation! Ready for 2019?
Insert patent-troll court hot air joke here.
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. A good read that should have been in TFS.
The company building it.
The gear to be used.
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.
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.
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 store power from wind or solar, but why store power from natural gas, which is already a storable form of power?
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
I just realized that ultimately any municipal services provider is fully funded by the taxpayer. Let's say that no "tax dollars" are used to produce this energy storage plant, so the costs of it are solely paid for by the consumers of the energy... which are the taxpayers for the local governments.
Even so the storage is probably a good idea, evening out power generation by the actively fueled plants means you can run them more efficiently. Say a nuclear plant, it runs enough to supply 110% of the power needs for the community, but during parts of the day the system needs extra plants online to meet demand, while at night the nuclear plant vastly exceeds power needs. Store the power overage from the low periods, then pump it into the grid during peak times. It's working to the strengths of all the situations.
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.
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?
Being US President gives you a fair statistical chance of spending the rest of your life in the job.
Please consider this account deleted, I just can't be bothered with the spam anymore.
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.
"I assumed blithely that there were no elves out there in the darkness"
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?
Make sure it doesn't swallow an entire lake:
http://en.wikipedia.org/wiki/Lake_Peigneur
It's a reasonable explanation with one caveat: use solar/wind for air compression power needs and it becomes massively more efficient.
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.
People in cars cause accidents....accidents in cars cause people
Agreed, however, once this system is online, switching the gas turbines for solar is 'relatively' straightforward. Call it Step 1 in a mult-step process. And given this is smaller than 'grid scale' it might be a great test bed for solar as well.
People in cars cause accidents....accidents in cars cause people
store the energy in the cloud? All the big IT firms are doing it these days.
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!
"I assumed blithely that there were no elves out there in the darkness"
They are burning gas!
Read Section 2!
TL;DR: It's a Brayton-cycle hybrid CAES setup, you heap of bloody idiots.
I thought space-based solar power was the future? I mean, Solaren is launching tons and tons of solar panels, right? Right? Hmm, you mean not a single bolt is in orbit? Well....
There are lots of reasons to use storage instead of another CT operating on natural gas (or, with a significant rejiggering of energy markets, oil). The first thing to understand is that ERCOT (the electricity grid in most of Texas) doesn't connect with the rest of the country. This means that all the electricity they need they must produce, AND all the electricity they produce they must need. The next thing to understand is that there is a electricity marketplace -- the generators bid in their prices, and the lowest generators get to produce. There is a spot price in real time -- most times electricity is a few cents per kWh, but sometimes it is 100 times that and sometimes it is negative! This means that if you can store, even if you lose some to thermodynamics, you can arbitrage the market. Buy low [very windy, middle of night, etc] and sell high [M-F afternoon, hot spell, temporary disruption to another plant, etc]. Additionally, you can sell ancillary services like frequency regulation.
Sure, you can do lots of this with a gas turbine, BUT you can't take excess energy off the grid, and you've got to pay for fuel. Right now, with interest rates so low, spending on capital projects with low operating costs and ongoing revenue just might be more fiscally prudent.
P.S. If Texas is to capitalize on the tremendous wind and sun resources the state is blessed with, they'll need dozens of these 300MW storage facilities. Ratepayers will see lower electricity prices, and more intermittent renewables will be able to be brought on the grid. Everybody wins.
Why not just store the natural gas in the same place they would be storing this compressed air? CNG has like a brazillion times more energy density than air plus it doesn't lose energy like the air will as it cools (they must have some insane insulation to even make it work in the first place).
This makes no sense.
"The plant is estimated to cost $350 million-plus, and will create about 20 to 25 permanent jobs."
Seriously, is there any conceivable business case for this? Aside from "My buddies in the legislature are going to give me several truckloads of cash, tax incentives, and a guarantee to buy the "new" power I generate at a premium price?"
But hey, $14 million per person seems a reasonable amount to spend to "create a job."
Three Squirrels
"The 'goodness' and cost-effectiveness of the job will be whether it a) reduces the ratepayer's bills, and/or b) increases utility profits (not sure of the regulatory structure out there), and/or c) increases the reliability of the grid.
I'm pretty damned sure it'll be:
a) No way in hell.
b) Goes without saying
c) Highly unlikely.
Three Squirrels
Considering the chain of events that happened at that lake, what could have possibly gone right?
I don't think it's fair to compare this scheme to complete idiots just because salt is involved.
there's no such thing as a perm job in the US
Comprehension tip: The job is permanent, not the employee.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
wouldn't it be more efficient to just burn the natural gas for the energy and push out the middle man (in this case compressed air?) Otherwise are you just losing energy when you transfer it from one medium to the other?
As each unit comes on line you get a sharp step in available power because you can't run them at half speed. If you a while you need the output of 1.1 units instead of 2 units then instead of firing up an entire unit (which runs at a fixed output anyway) you can use a bit of power from pump storage, which is what this compressed air scheme using offpeak power is a version of.
Also tens of minutes to fire up is a long time when something has unexpectedly gone offline. Hydro and pump storage (plus compressed air) can come on line a lot quicker than that.
As an aside, one proposal for offshore wind power is to compress air instead of directly generate electricity. It's offshore because you can store the air by inflating balloons at a depth corresponding to whatever pressure you want instead of having large expensive pressure vessels (just like the salt dome idea to get around that). That way you can provide continuous power over time from a power source that is not constant. The energy losses are large, but the alternative is typically burning a lot of fuel in a large thermal unit for little gain (instead of full capacity for the unit for about the same fuel), so even lossy things like compressing air can be worth it.
It will be horribly inefficient, but there's not really an efficient way to follow electricity demand anyway (unless you've got a lot of hydro) so it becomes better than alternatives. This sort of thing is to fill the gaps in demand without bringing a whopping great big thermal unit on line to burn as much fuel as it needs for 350MW when you only need 5MW.
Batteries suck and we're a long way from the capacitor out of the old Batman movie so this idea takes whatever electricity is in excess and stores it with compressed air. I suppose it can be done on a smaller scale than solar thermal so a pilot plant has a lower capital cost.
You don't really need the numbers on efficiency. The numbers will be bad. It's instead about getting something out of what would typically be wasted.
You are correct and the article is misleading. The natural gas plant just happens to be nearby but the plan is to use offpeak power from the grid, store it, and feed it back when needed to more closely match the supply curve (which is in great big steps as each unit comes on line) to the demand curve.
The price of the project and the amount of permanent jobs created really don't need to, or should they compare to each other. I worked at a power station with 44MW aeroderivative gas turbines. The plant had 5 of them. Each one cost about $50 million new and there were 6 full-time employees plus 1 summer intern (me). As far as direct permanent jobs created per dollar, that's pretty poor. But you know what? Those turbines need maintenance. Every year a crew of 10-20 guys come in for a couple weeks to tear the machine apart and rebuild it. The plant provides reasonably inexpensive electricity when it is needed most. Without it, during very hot days, factories would be asked to shut down to conserve electricity. Just because a project doesn't employ hundereds or thousands of workers doesn't mean it is not beneficial to society. The fact that such projects can be so human-efficient speaks well to how advanced the US is compared to some countries.
I'm speaking in general terms, by the way. Compressing a gas is probably the worst way to store energy I can think of.
Sort of. One of the coal seam gas ideas is to put in a horizontal bore, start a fire at one end and pump air in from the other. Incomplete combustion means that the gas that comes out can be burnt to drive a power station above ground, plus the gas is already hot. The idea is that the coal is burnt out in a gallery around the horizontal bore because that's the only place that air is supposed to be. There's been some tests that worked as planned.
I don't know enough about to to know if it's a good idea or a way to start an unextinguishable fire.
Someone mod this up. You'd have to be retarded to use natural-gas-generated electricity to operate an electric compressed air storage plant
You're forgetting who's paying for all of this.
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.
A better use of an underground salt dome would be for storing oil, as is done in the strategic petroleum reserve. As long as oil remains in contango it's like printing money.
http://blogs.wsj.com/marketbeat/2012/06/22/contango-may-be-tipping-point-for-oil/
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 figured that was going to happen sooner or later.
In North/Central Florida, we get sinkholes from over-pumping of the aquifers, Houston has had whole neighborhoods sink into Galveston bay from industrial scale water extraction. This is just another way to create "acts of God" risk for the insurance industry to deal with.
With all the HOT air coming out of that town, should be enough to power every turbine in the USA LOL.
I just want to add something that might be escaping some people.
It's not "escaping" us. TFA doesn't give any information on relative efficiencies... or why the CASE plant would be profitable.
There seems to be some confusion in the thread. This isn't some new/offbeat method to generate power. It's an old/offbeat method to store power. Many power plants use methods for storing power when demand is low. Most pump water uphill and use the potential energy to meet a rising demand. Some efficiency is lost but it allows them to keep generating power (read cash) until the power can be sold. On a side note: Utilities count the stored power as actual assets on their balance sheets.
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http://www.gofundme.com/help-sherry
I wasn't speaking to the article, I was expounding on the parent's claim of efficiencies and explaining why it would be efficient to store energy instead of manipulating the production.
Wouldn't it be more efficient to store the energy as, say, natural gas, which you can burn in a natural gas generator to create electricity when you need it? I mean, given that it's already stored that way to start with...
Chuck Norris: Socialism == a thousand years of darkness.
you can just pump air outside, increasing ambiant pressure - it will be there when you need it.
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.
Not all of it. Gas compresion heats up the gas, and if that heat escapes before the gas is decompressed, usable energy is wasted. AFAIK, this is the reason why gas compression is not normally use for storing energy. It would be interesing to know how/if they avoid this problem, but the best way to check that is RingTFA, and there is no way in hell I am going to do that.
Not saying they haven't thought of it and engineering for it. Just interesting numbers:
Storage pressure of around 2000psi in a natural cavern provides quite the energy potential. They say they can generate 300MW for 100 hours from the full cavern. It's not quite in the nuclear class, but if I ran my numbers right, we are talking energy storage on the order of 1/10 of a megaton.
Enjoy life! This is not a dress rehearsal.
Just how efficient will this be for energy storage? Profitably so? I think I smell an application for an energy department loan for an Obama-supporter-owned firm for millions/billions with a bankruptcy filing shortly thereafter. This is becoming a new business model: Obama borrows money from China, loans it to a supporter's company, the company goes bust and Obama does nothing to claw-back the loan, the supporter lives in luxury and funnels some money to Obama campaign... and the star-struck kids who supported Obama are left to work to the age of 90 paying interest on the trillions of new debt their messiah ran-up.
How much energy is lost converting electricity on the grid to air pressure? (pneumatics are notoriously bad in this regard)
then, how much energy loss occurs through air leakage? (Is somebody going to line an entire underground salt dome with something to make it air-tight?)
How much energy is lost converting the air pressure back to electricity? (again, the notoriously bad transformation)
Compressed air is like Tesla stuff... very popular among people who imagine clean, safe, future utopias and by would-be-inventors. People have proposed air-powered robots, factories, monorails, etc and have even built the occasional full-scale demonstrator (including a full-scale pneumatic railroad locomotive) but everybody who actually tries the stuff, instead of just dreaming of it, runs into the same problems
Hint: There are very good reasons why we see stories every few years about compressed-air-powered cars but no major car company ever produces them...
Caes sensitive
Waiting for an amusing sig.
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 industry. All this bad press will have to be covered as well, so a few dozen journalist jobs, some additional printing press jobs and a couple more paperboy jobs. Any damages caused by it will have to be paid out, so that's jobs for lawyers (on both sides), insurance companies and accountants. Since the government will want to tax that money, expect the IRS to create a few additional jobs as well.
So in the end everything works out just fine.
Slashdot social media options: AIM, ICQ, Yahoo, Jabber and Mobile Text. Why no MySpace?
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 how bad the efficiency of their gas turbines would have to be, at less than full tilt, for them to consider this a good idea.
I am John Hurt.
I'm more interested at what efficiency the compressed air turbines will operate at.
I am John Hurt.
Indeed - I would be very happy if the modern world could work and produce food, energy, houses, bikes, cards, with the creation of *no* permanent positions. That way I could enjoy the fruits of that labour without having to go to work every day. The concept of job creation being a good thing is fundamentally wrong. It is bad that this project creates jobs, it would be much better if it could be done without people having to monitor/fettle it all the time. Then those people could spend time playing pool and running up mountains instead. The idea that somehow having someone staring at a computer screen creates wealth is madness.
KÃse-sensitiv
In doing some quick research, I couldn't find an energy input vs output ratio for a CAES system, given an assumption that a large amount of energy in the form of heat will be lost to the surrounding earth. I would assume that theoretically it is 100% in perfect thermal isolation, and that in this situation, the energy lost is equal to the amount of energy required to heat the resulting volume of air at the resulting pressure by the difference of the heat of the gas after compression and its original temperature. I can't be bothered doing the math to get a theoretical percentage, and I didn't see the expected volume of this project nor the expected pressure.
I would, however, be interested to know if there's research out there that compares the actual efficiency of a CAES system (like the one originally built in Germany) against modern methods of obtaining hydrogen from water and compressing that into an easily stored liquid. Last I heard, there were new advances in that field and likely more promising results to be had in the future, so to me it would appear that hydrogen would've been a better bet. Or maybe these liquid metal batteries?
Normally, CAESes, such as the on operating in Huntorf in Germany, IS burning natural gas. When storing energy, the air is pumped into the caverns. When extracting it back, the air may just turn the turbine directly, but this way, a lot of energy will be lost - the pumped air storage is tightly sealed, but the compression heat is inevitably leaking from the cavern.
What they normally do instead - they use compressed air as the input for a turbine burning natural gas - this way it does not need it's own compressor, making it more efficient than a conventional turbine. From 0.8kWh of stored electricity and 1.6kWh (thermal) of natural gas, they produce 1kWh of output electricity. Burning 1.6kWh gas in a normal turbine with 50% efficiency would produce 0.8kWh electricity, so the overall efficiency of this storage is just about 50% - or even less if you consider more efficient gas-and-steam power plants. Maybe this new CAES will utilize some more efficient technology, but don't expect wonders from it - this type of storage has quite high losses.
The CAES were never about storing power efficiently, their main advantage is the ability to power up really quickly. The Huntorf CAES for example is able to reach 50% output in just 3 minutes, and full output in under 10 minutes.
"The 'goodness' and cost-effectiveness of the job will be whether it a) reduces the ratepayer's bills, and/or b) increases utility profits (not sure of the regulatory structure out there), and/or c) increases the reliability of the grid.
I'm pretty damned sure it'll be:
a) No way in hell.
Yes.
b) Goes without saying
Yes.
c) Highly unlikely.
Are you high? On-demand, fast-spin-up capacity is GREAT for the grid, the more so when it's highly rampable.
Okay, one plant won't help (much), but dozens will, and you gotta start somewhere.
Technology practice for larger greener projects.
You can use compress air to spin a gas turbine just as easily as you can burn fuel to do it, in the same turbine. Gas turbines can also be used to create compressed air (bleed air for those of you in the aviation field).
But the main thing is, and you are correct you store your compressed air when it is cheap to generate (at night whether it be wind turbine or fuel based generators that can be run at peak efficiency 24/7) and then sell it at peak times.
Bill Gates made several billion dollars a year at his job. How about spending $350 million dollars to create 20 copies of his job?
For those of us with a few operational brain cells realize that the $350M goes for more than just the 20 jobs (except if you are a liberal/idiot) if it creates a profit of say $35 million dollars a year and will stay operational for 20 years we get a nice 10% return anual return on investment and 20 people get a new job.
Better yet if this things ends up working very well and you'll end up seeing it copied in say 100 places around the country. Now 2,000 people get a job, $3.5Billion in profits are generated every year, the price of electricty goes down a little for everyone since there is now more peak electricity available, the environment gets a break since fuel efficience goes up for the power plant operators, and more wind turbine companies can sell their off peak electricity at a bettert price since there will actually be demand for it at night from these facilities.
Sounds like a pretty bad way to spend $350 million dollars.
Isn't the point of this to put the compressed air into the ground at night when bulk electricity is cheaper ( to power the pump )
and then generate power during the day when it's more expensive?
Any significant heat you guys keep talking about would happen in the DAY. That would only enhance generation.
Pfft. Sounds like another Aperture Science cover story to me.
+1, Cheesy
Escher was the first MC and Giger invented the HR department.
If you don't like the throws, get a new pitcher.
That does make a lot more sense.
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.
Apocalypse Cancelled, Sorry, No Ticket Refunds
Actually doing it on purpose seems to be an idea fraught with risk unless it's a limited deposit and you know for a fact where all the coal runs and there's nothing above it you care about. The insulation provided by the ground is significant so unless the air can be cut off 100%, you'll probably end up with a fire you can never put out because everything stays above the flashpoint of coal all the time.
I was more thinking of places where there are already underground coal fires that they can't put out. As long as all that coal is going to burn anyway, it would be nice if you could make use of it. I don't know anything about the logistics and safety of drilling into rock that's actually on fire, however. I suppose the method you mentioned could be quite viable in coal deposits on the edge of existing coal fires. If it's not on fire now, but you know that it's inevitable it will catch fire, then you could set up the system you mentioned. I don't know much about how fire spreads underground either, of course.
My rough guess is if it's fractured enough to let enough air in for fires to be a problem then it's fractured enough that it's hard to get more than a small amount of the gas out from any point. If you could seal off all but one point practically then you'd be able to put the fire out anyway. However I'm an engineer not a geophysicist, and the geophysicists I work with deal with different stuff.
Maybe this would be better if is was hydro powered rather than gas powered.
Trompe power generation is highly effective but has been ignored by the mainstream for some time now.
http://en.wikipedia.org/wiki/Trompe
http://www.cobalt.ca/index.php/ragged-chutes
The problem basically boils down to scale. Most of us have done the experiment where you put out a candle flame with CO2, then wait for a bit, then introduce air again and the candle lights up again. It doesn't take an incredibly long time for the wick to cool enough that it won't light again, but it takes longer than intuition leads most people to believe, and a candle wick is tiny. When the heat is stored in a giant mass of coal underground, the heat can only be lost by conduction to the surrounding earth. The more you scale it up, the more 3-dimensional mass you have relative to the 2-dimensional borders where the heat is conducted away. So, if you get it hot enough to burn when there's oxygen in a large enough mass, it will stay hot enough to catch fire for decades or possibly centuries even without any oxygen getting in.
Now, if you're removing heat by pumping out gas, that's a faster way for heat to escape, but if the fires keep burning, the average temperature of the surrounding rock is going to go up and up and up and the fire is going to spread if there's flammable coal and any way for oxygen to get in. The idea seams to have the potential for uncontrollable disaster written all over it.
Of course, if you know the geology of the particular area well enough, then you can probably be pretty sure of whether or not it's even possible for it to get out of control. If you have an "island" of coal that you plan to completely burn anyway, then it's probably not an issue. Similarly, if it's already doomed to burn.
I worked on a gas pipeline in the 70's. Since the terrain was uphill and downhill, one could not test the 40 inch diameter pipes (1 meter diameter) with water, as the pressure would not be evenly distributed. One had to pressurize the pipe to 1035psi. Normal operation was around 935psi.
The 1 mile section of pipe was laid open pit, awaiting the pressure test. The test was using natural gas and was going fine until a longitudinal weld gave way. In a fraction of a second, at a speed of a race car, the split went along the pipeline, as if a scissors was cutting it open, without having to move the scissor's jaws. And the damn thing caught fire. People from hundreds of miles on both sides of the pipe saw the large 1 mile flare. More than 1 mile of pipe had to be replaced. No lives were lost. By the way, first there was frost as the gas expanded and dropped in pressure, then it was followed by extreme heat as the gas burned away. Losses included widlife, and trees.
So accidents with pressurized caverns can also blow, and when it does, if the pressure is high enough, the result could appear as a localized volcano, spewing debree onto homes, cars, people.
Just an interesting bit of my past working experience.
Leslie Satenstein Montreal Quebec Canada
If you wind it down to generate less electricity it becomes less efficient and degrades the engine components faster so it's avoided.
This is not really correct. To much simplified.
A gas turbine is connecte 1:1 to the generator, with no gearing.
As the grid frequency in germany is 50Hz, so the turbine is running at 50 * 60 that is 3000 rounds per minute.
The turbine is running with that speed regardless how much power is drawn from the grid.
Is there now power demand, that means higher load on the grid, the frequency goes down. That means the generator and the turbine rotate slower. That means you have to put in more gas to creater more power and hold the turbine at 3000 rpm.
All that has nothing to do with "efficiency! but only with grid frequency. OFC the turbine is designed to be very efficient at 3000 rpm.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
Temps are lower so you can use cheaper alloys / spin it faster and you don't have to deal with igniters and gas injection.
The turbine will always spin with the grid frequency, 3000 rpm in europe, 3600 rpm in the USA.
There is no speed difference between NAT gas trubines or air turbines.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
Shakespeare smart this one...
Happiness in intelligent people is the rarest thing I know.
Ernest Hemingway