I know several people are interested in wind turbines running air compressors...

[kristopher]

General Compression Achieves Proof of Concept, Obtains Rest of $20 Million in Venture Capital

Newton, Mass. – General Compression, the developer of a compressed air energy storage technology, announced on Wednesday that it has successfully achieved proof of concept for its system, triggering the second tranche of its $20 million first round of venture capital.

Founded in 2006, General Compression has developed a system based on advancements in the fields of isothermal compression and expansion to provide utility-scale storage for renewable electricity sources such as wind and solar. The company’s “near-isothermal” compressor/expander module is intended to create 2.4 megawatt to 1,000 megawatt, 8-to-300 hour discharge, compressed air energy storage projects.

“Achieving the Tranche II technical...

http://smartenergynews.net/2010/10/20/general-compression-achieves-proof-of-concept/

[JDPriestly]

1. If someone could please explain this?

Although I don't understand it, it sounds encouraging. (Does that make sense?)

Anyway, it's investors sound serious.

Investors in General Compression include US Renewables Group, Duke Energy and Northwater Intellectual Property Fund.
The company has also received $750,000 in research and development funds from the U.S. Department of Energy.

http://smartenergynews.net/2010/10/20/general-compression-achieves-proof-of-concept/

[spinbaby]

2. What I think it is

is a method to get around the problem of wind energy not always matching demand--sometimes the wind blows while demand isn't there and sometimes demand is there while wind doesn't blow. This is like a giant battery.

[Defectata]

3. This is new?

The pennsylvania amish have been doing this for years! Their windmills power air compressors and fill storage tanks, from which they power tools.

Maybe more efficient, but by no means new.

[madokie]

5. A local trim shop used to have a wind turbine that had a compressor rather than a generator

and they had a huge tank that they pressurized to run their many air powered tools. I said used to because the man who did this died from old age and I don't think his trim shop is anymore. I personally like the idea of having a hydraulic pump connected to the blades and then have the generator at ground level, sizing the pump to the motor to achieve the required rpms for the generator. On a home system like I might could build I could use two of the legs for the tower as the piping for the hydraulic fluid to flow in.

[Ghost Dog]

4. "Compressed air is stored in the same types of geologies that are used to store natural gas."

Obvious question: how common/easily accessible are such types of geology, and how often located close to ideal wind power sites?

[StandingInLeftField]

6. And speaking of compressed air, it's also good to run inner-city cars!

http://www.gizmag.com/compressed-air-car-set-for-us-launch-in-2010/8896/

Wind-power to compressor to compressed-air car! Bingo! We have a WINNA!
Not sure if it's made it here yet, but saw it on one of the car shows on tv - very zippy!

[madokie]

7. Are you sure that isn't just a bunch of hype

I first seen this about 3 or 4 years ago and other than this I've not seen anything about it anywhere else

[kristopher]

8. It has the advantage of low capital cost (you could buy one cheap)

the disadvantages are that the amount of energy density you can achieve in a portable system and still keep it cheap make it worthless as a means of transportation.

I believe it was promoted by an Indian company called Tata.

[StandingInLeftField]

9. I haven't seen anything in this country yet.

Digging deeper, it also looks like the French MDI/Indian Tata Motors joint effort has gone nowhere. Popular Mechanics ( http://www.popularmechanics.com/cars/alternative-fuel/news/compressed-air-car-myth ) puts the kabosh on the compressed air car. Perhaps in light-weight motorcycles, but not in cars for the forseeable future.

Still, I think in the long run the kinks could be worked out. At least I hope so.

Thanks for the reality check, madokie.

[newfoxnose]

10. quite intreresting

how big is this market?

http://wind-turbine-manufacturers.com

[Javaman]

11. Is there a benefit to using compressed air over flywheels? nt

[phantom power]

12. I wonder how you make a geologic feature "near isothermal"

[Nihil]

13. Usual way ...

... pixie dust ...

Didn't you know that by now?

<sigh>

[kristopher]

14. Perhaps by learning to read?

They are saying the do not use combustion like other compressed air systems but they are still achieving a similar round trip efficiency. My guess as someone who DOES know how to read is that their cycle captures the heat from compression and reintroduces it during expansion.

Beats the hell out of filling those "geologic features" with nuclear waste.

[phantom power]

15. I suppose you could play games with heat pumps

pump heat out of the air prior to compression, so that its compressed temp == ambient geologic temp. pump it back on decompression. At least in theory that could be better than combustion.

It always seemed like a lot of trouble. Just take the non-adiabatic loss and be done.

[kristopher]

16. Prior to compression?

Riiiiight.