OT: 500 megawatt compressed air power storage

[crickets]

To you maybe. For those of us who study the metanarrative that encompasses "climate crisis" theory; what Scott is telling you is true.

There are only two outcomes Gus:

1.) A massive reduction in human population

2.) A massive reduction in quality of life and liberty for the human population

Or both...

We are already getting both but for the opposite reasons. In addition to climate change induced disasters you can add effects of pollution. While pollution is a huge problem in developing countries, we're not free of it either - sufficient to pull up the cancer studies to see how we're affected.

 

[crickets]

• Solar cells produce nothing during the hours of darkness and little during the transition periods when the sun is at extreme angles.

Which is why we typically oversize the systems - to have excess production during the production hours which spreads out over non-production hours.

• Wind can blow more or less steady for days and then drop suddenly. If that happens at night it would be catastrophic without reliable backup.

Which is why we're diversifying generation sources and developing storage systems with different runtime parameters.

• The elites have not only promised but demanded the elimination of all carbon emitting uses within a relatively short time frame.

That's politics. Engineering is what we should be talking about.

• Storage technology is currently only a small portion of grid capacity and future storage is often limited by geography with the alternatives being much more expensive.

It's obvious that pumped hydro is a non-starter for the flat states like Kansas or North Dakota, but it doesn't mean that those states can't benefit from pumped hydro. At this time we have the preference for local generation (and storage) primarily due to high losses in the transmission lines. Most of our transmission lines are AC and are basically outdated by at least half a century. Replacing AC lines with HVDC lines solve quite a bit in that department.

 

[john.k]

Funny (tragic) story.....the old 1950s Snowy Hydro scheme was a nation building exercise .......about 20 years ago ,it was decided to enlarge the scheme.....still very little has happened apart from a multitude of lawsuits by green groups over everything from 'wild water ' to 'anus breathing frogs'........more money than the original scheme cost has been wasted on reports ,surveys ,papers,political posturing,lawyers etc............in fact the net result so far is output from the original scheme is reduced due to a 'wild rivers ' lawsuit diverting more water around the scheme.

 

[Scottl]

Which is why we typically oversize the systems - to have excess production during the production hours which spreads out over non-production hours.



Which is why we're diversifying generation sources and developing storage systems with different runtime parameters.



That's politics. Engineering is what we should be talking about.



It's obvious that pumped hydro is a non-starter for the flat states like Kansas or North Dakota, but it doesn't mean that those states can't benefit from pumped hydro. At this time we have the preference for local generation (and storage) primarily due to high losses in the transmission lines. Most of our transmission lines are AC and are basically outdated by at least half a century. Replacing AC lines with HVDC lines solve quite a bit in that department.

I agree that storage systems will solve some of the issues but differ as to the practicality of being able to build as many as would be needed if solar and wind become major players in generation. From an economic point storage works better with solar than it does with wind as it is more predictable.

The first article in a recent post by another member uses a lot of phrases (emphasis added) like "possible evolution of energy storage", "potential coming wave of energy storage", "could range from 130 gigawatts to 680 gigawatts in 2050". The second article takes a more detailed approach and analyzes the various storage methods for suitability in different uses. They determined that pumped hydro and compressed air were ill-suited for fast response situations and that flywheels and supercapacitors are not suitable for longer term applications. They found that batteries are the most likely to have the lowest projected Levelized Cost of Storage as stated here "Projected cost reductions for battery technologies limit the competitiveness of pumped hydro and compressed air. Battery technologies exhibit the highest probability of lowest LCOS in most applications beyond 2025. By 2030, lithium ion appears to be most cost efficient in most applications, in particular with <4 h discharge and <300 annual cycles such as power quality and black start."

It is an interesting read, although not a quick one. I am repeating the link so people won't have to search for it.

Projecting the Future Levelized Cost of Electricity Storage Technologies

This study determines the lifetime cost of 9 electricity storage technologies in 12 power system applications from 2015 to 2050. We find that lithium-ion batteries are most cost effective beyond 2030, apart from in long discharge applications. The performance advantages of alternative...

www.cell.com

One thing I find interesting is that in the graphical abstract comparing projections for 2030 and 2040 compressed air storage (CAES), green in the graphic, seems to completely disappear by 2040 and be replaced by hydrogen. They also show a significant percent of pumped hydro being replaced by lithium ion.

 

[crickets]

I agree that storage systems will solve some of the issues but differ as to the practicality of being able to build as many as would be needed if solar and wind become major players in generation. From an economic point storage works better with solar than it does with wind as it is more predictable.

True, solar is fairly reliable in certain geographies. We would still like to harvest the wind for many reasons, and it's not particularly difficult to store energy for months at a time. Both pumped hydro and compressed air discussed here are infinitely scalable and can store energy for many weeks when the wind is down. Both have drawbacks and concerns, but the tech does exist. We also have the tech to convert electrical energy in to chemical and store it that way - that direction has no particular drawbacks other than its low cost efficiency at this time. Few entities want to spend money on R&D for how to make gasoline out of air when it's so cheap to refine it from the petroleum.

One thing I find interesting is that in the graphical abstract comparing projections for 2030 and 2040 compressed air storage (CAES), green in the graphic, seems to completely disappear by 2040 and be replaced by hydrogen. They also show a significant percent of pumped hydro being replaced by lithium ion.

Lithium Ion is great for daily cycling and emergency standby, but it's not a full replacement for pumped hydro. Indeed pumped hydro has been often used for daily cycling, but it can be used for long-term energy storage which Lithium Ion isn't suitable for.

 

[Bill D]

A few links about natural gas storage i nthe ground with leaks.
Bill D

https://pubs.acs.org/doi/10.1021/cen-09409-notw1

Leak at Pennsylvania gas storage well spewing methane

A vent at an underground natural gas storage well in Western Pennsylvania has been spewing massive amounts of planet-warming methane into the atmosphere for more than 11 days and attempts to plug the leak have thus far failed

abcnews.go.com

 

[Scottl]

A few links about natural gas storage i nthe ground with leaks.
Bill D

https://pubs.acs.org/doi/10.1021/cen-09409-notw1

Leak at Pennsylvania gas storage well spewing methane

A vent at an underground natural gas storage well in Western Pennsylvania has been spewing massive amounts of planet-warming methane into the atmosphere for more than 11 days and attempts to plug the leak have thus far failed

abcnews.go.com

At least compressed air would not change the makeup of the atmosphere although if the pressure leaked into water wells or other such it could be dangerous.

 

[tdmidget]

At least compressed air would not change the makeup of the atmosphere although if the pressure leaked into water wells or other such it could be dangerous.

I get the feeling that no one here has come to grips with the number required for this pipe dream.
For the moment , lets ignore those pesky inefficiencies. For each hour of 500 Mw you will need 670241 hp of compressor capability and remember that is 100% efficiency. Where will you get it? Where will you put it? You would have to cover miles of land to generate that with solar panels and last I looked that land has value. Even if you did that somehow you cannot get that power back from a turbine. You need that air to expand in a turbine and the refrigerant effect would be astronomical. You would not be able to recover all the energy because the air can only expand to atmospheric pressure at best where steam is condensing and creating a vacuum and allowing more expansion.
But again, ignoring such losses let's look at it. Modern Diesel electric locomotives produce 4000HP or there abouts so you will need 168 such engines and comparable compressors to compress the air. That is with no backup units. That might give you some idea of what a fantasy this is.

 

[crickets]

I get the feeling that no one here has come to grips with the number required for this pipe dream.
For the moment , lets ignore those pesky inefficiencies. For each hour of 500 Mw you will need 670241 hp of compressor capability and remember that is 100% efficiency. Where will you get it? Where will you put it? You would have to cover miles of land to generate that with solar panels and last I looked that land has value. Even if you did that somehow you cannot get that power back from a turbine. You need that air to expand in a turbine and the refrigerant effect would be astronomical. You would not be able to recover all the energy because the air can only expand to atmospheric pressure at best where steam is condensing and creating a vacuum and allowing more expansion.
But again, ignoring such losses let's look at it. Modern Diesel electric locomotives produce 4000HP or there abouts so you will need 168 such engines and comparable compressors to compress the air. That is with no backup units. That might give you some idea of what a fantasy this is.

Technically a lot of your questions are answered in the link in the first post. There is a mention of heat exchangers that will be used to evacuate heat into some kind of medium. That heat can then be recycled during the generation cycle to warm up the air. Practical efficiency for adiabatic systems is expected to be around 70%. They don't mention their compressor capacity, it's likely that they will not be compressing at full 500MW, but rather do a fraction of that. So effectively it will be a system that will "charge" slowly and "discharge" fast if needed.

 

[crickets]

Here is an article about a system of comparable size in China, which is already in operation:

China turns on the world's largest compressed air energy storage plant

The world's largest and, more importantly, most efficient clean compressed air energy storage system is up and running, connected to a city power grid in northern China.

newatlas.com

 

[Scottl]

I get the feeling that no one here has come to grips with the number required for this pipe dream.
For the moment , lets ignore those pesky inefficiencies. For each hour of 500 Mw you will need 670241 hp of compressor capability and remember that is 100% efficiency. Where will you get it? Where will you put it? You would have to cover miles of land to generate that with solar panels and last I looked that land has value. Even if you did that somehow you cannot get that power back from a turbine. You need that air to expand in a turbine and the refrigerant effect would be astronomical. You would not be able to recover all the energy because the air can only expand to atmospheric pressure at best where steam is condensing and creating a vacuum and allowing more expansion.
But again, ignoring such losses let's look at it. Modern Diesel electric locomotives produce 4000HP or there abouts so you will need 168 such engines and comparable compressors to compress the air. That is with no backup units. That might give you some idea of what a fantasy this is.

While it CAN be done technologically the costs in dollars, real estate, and various other less defined categories would be enormous. Most of the true economics is glossed over making it very difficult to gain a true picture of the total cost of "going green" by 2050, the date set as a goal by multiple governments. I have seen estimates from other countries of annual expenditures that are a significant percentage of GDP. If so that would validate my assertion that total expenditures over the next 27.8 years would indeed be several times any given year's GDP.

The whole thing is based on a theory not only that carbon emissions will cause catastrophic climate change we can not adapt to, but also that carbon released by humans greatly outweighs that from natural processes and the result is that we are being pushed into what I call a "Mars colonist" mindset as to our future lifestyle.

 

[Scottl]

Here is an article about a system of comparable size in China, which is already in operation:

China turns on the world's largest compressed air energy storage plant

The world's largest and, more importantly, most efficient clean compressed air energy storage system is up and running, connected to a city power grid in northern China.

newatlas.com

I note that the article mentions the use of "supercritical thermal storage, supercritical heat exchange, high-load compression and expansion technologies" which I suspect are not only expensive to operate but also likely high maintenance. If so, total operating costs could easily outweigh the low capital cost claimed. Since the article was from last October and the plant had just been made operational it would be interesting to see more recent information.

Update: A brief web search failed to turn up a single 2023 article reporting on that installation and how well it is working. After more than three months of operation the lack of such reports from a nation that always trumpets its success and remains silent on its failures is interesting.

 

[Scottl]

Currently we know that compressed air systems that use existing structures such as caverns can be economically viable BUT the sticking point for some critics is that they must burn some natural gas in the expansion process. Since the original usage was to store off-peak output for later sale as a cost saving measure it is a safe assumption that the amount of gas used was far less than what would be required to generate the same amount of electricity directly. This ties in directly with my assertion that the "greens" refuse to accept practical reductions in burning of fuel with their (likely impossible) demands that we must achieve zero carbon. I maintain that steady progress in cleaner air and more efficient use of energy is the practical approach regardless of whether human caused climate change existed or not.

A fleet of modern gasoline burning automobiles emit the same pollution as those of 40 years ago and it would take about 60 modern diesel trucks to equal the pollution from a single older truck. In the same manner a neighborhood full of modern oil burning heating systems are equivalent to one of the old black soot producers.

Always beware those who present you with both the problem AND the solution, especially if they tell you the solution must be implemented in urgent haste.

 

[crickets]

Currently we know that compressed air systems that use existing structures such as caverns can be economically viable BUT the sticking point for some critics is that they must burn some natural gas in the expansion process. Since the original usage was to store off-peak output for later sale as a cost saving measure it is a safe assumption that the amount of gas used was far less than what would be required to generate the same amount of electricity directly. This ties in directly with my assertion that the "greens" refuse to accept practical reductions in burning of fuel with their (likely impossible) demands that we must achieve zero carbon. I maintain that steady progress in cleaner air and more efficient use of energy is the practical approach regardless of whether human caused climate change existed or not.

A fleet of modern gasoline burning automobiles emit the same pollution as those of 40 years ago and it would take about 60 modern diesel trucks to equal the pollution from a single older truck. In the same manner a neighborhood full of modern oil burning heating systems are equivalent to one of the old black soot producers.

Always beware those who present you with both the problem AND the solution, especially if they tell you the solution must be implemented in urgent haste.

Which is why this should be about technology and not politics. The moment you go on a tangent to accuse "greens" of being dumb, you start making your own technical mistakes. Most of the current systems in operation are diabatic. When stuff heats up in the compression cycle, they vent that heat into the atmosphere. Then when they discharge the air for power generation they use natural gas to reheat it. That is obviously inefficient, and not very green. New class of systems is adiabatic, that is what "A" in A-CAES stands for. They use heat exchangers to transfer the heat into a medium that retains most of it across the compression/decompression cycle, and use it again to re-heat the air on discharge.

 

[Scottl]

Which is why this should be about technology and not politics. The moment you go on a tangent to accuse "greens" of being dumb, you start making your own technical mistakes. Most of the current systems in operation are diabatic. When stuff heats up in the compression cycle, they vent that heat into the atmosphere. Then when they discharge the air for power generation they use natural gas to reheat it. That is obviously inefficient, and not very green. New class of systems is adiabatic, that is what "A" in A-CAES stands for. They use heat exchangers to transfer the heat into a medium that retains most of it across the compression/decompression cycle, and use it again to re-heat the air on discharge.

Then would you please provide example of adiabatic systems that are currently online and operational, especially any with efficiency data?

The traditional meaning of adiabatic was essentially zero loss to the environment whereas although an A-CAES system captures and stores much of the heat I doubt it is 100% efficient.

Also, while you say "this should be about technology and not politics" you criticize the use of natural gas in a CAES system as "obviously inefficient, and not very green". From a purely technology standpoint it is more efficient from a complexity standpoint, which is why it is the system in most common use. Also, it is certainly more green to use a much smaller amount of gas than direct generation. I think your response exactly illustrates my point about demanding no usage of fuels rather than allowing for reduced usage over time, going to zero only if technology development allows it.

 

[crickets]

Then would you please provide example of adiabatic systems that are currently online and operational, especially any with efficiency data?

The traditional meaning of adiabatic was essentially zero loss to the environment whereas although an A-CAES system captures and stores much of the heat I doubt it is 100% efficient.

Also, while you say "this should be about technology and not politics" you criticize the use of natural gas in a CAES system as "obviously inefficient, and not very green". From a purely technology standpoint it is more efficient from a complexity standpoint, which is why it is the system in most common use. Also, it is certainly more green to use a much smaller amount of gas than direct generation. I think your response exactly illustrates my point about demanding no usage of fuels rather than allowing for reduced usage over time, going to zero only if technology development allows it.

You're walking in circles. I basically agreed with you that diabatic systems aren't the way to go, and a careful distinction should be made.

Take a look at Hydrostor Goderich A-CAES plant that has been in operation since 2019.

 

[Scottl]

You're walking in circles. I basically agreed with you that diabatic systems aren't the way to go, and a careful distinction should be made.

Take a look at Hydrostor Goderich A-CAES plant that has been in operation since 2019.

I did take a look at the company's website and it appears to be a somewhat small scale proof of concept project. The claims re cost and life are impressive but no actual figures or technical data. Also, although they talk about purpose built storage containers this site apparently uses an old salt mine.

One interesting proposal I saw elsewhere was to have windmills directly compress storage air, eliminating the need to generate electricity twice. Such a system would be used to level out the variable output of windmills.

 

[Pete Deal]

Only in Kalifornia.....

Hopefully!

 

[gustafson]

Obviously compressed air storage has a limited utility, as does pumped hydro, both requiring specific conditions and space. Battery storage[being done now on utility scale] is much easier to collocate with generation

 

[Bill D]

Some people are bit confussed about the storage system. It is not a cavern or cave. It is simply air pumped down a deep well into a existing sealed layer of stone that has enough porosity to hold air. Much like water, oil and gas can be pumped out of rock layers.
there are lots of abandoned oil and gas wells in that area that would probably work..
Bill D