Friday, May 9, 2008

Compressed Air as an Alternate Energy Source?

By A.R. Tinkerer

New Name
To start with, I have some minor bad news. I discovered that AirNergy is a registered trademark of Global Energy; WindPower, Inc.
Because of this, I will no longer be using AirNergy as the name for this blog. As of this post, the name will be PneumoNergy (pronounced nu-mon-r-je).

850 AirMagnum Conversion
For those who are waiting for another installment about the PCP conversion for the 850 AirMagnum, I made a face spanner wrench to open those stubborn valves. Find out more about what happened in the next post.

Gas Prices
The way gas prices are going, alternate sources of energy are looking better and better. What upsets me is that gas companies are making record profits while they continue to raise prices. This has gone on at least since 2005, if not earlier (see the MarketWatch graph)! Note that they claimed 2007 would be a more difficult year to follow up with record profits.

2005 profits
ABC News

2006 profits

2007 profits
International Herald Tribune
Daily Mail
San Francisco Chronicle

The New York Times

Practical Uses
There are companies currently working on using compressed air as an energy storage mechanism for small cars and trucks, see
Introducing AirNergy. Compressed air could also be used an energy storage system for other uses. Air engine generators could run off the compressed air to generate electricity, and pneumatic tools could run directly. Hydro, wind and solar sources (have you heard about the new solar panels that are 1/10 the cost of the old ones?) can be used to compress the air, and compressed air has an advantage over batteries because of the lack of chemicals!

Hobby Uses
Compressed air engines could be used to power R/C vehicles (with small batteries running the electronics).
Mike Smith's Compressed Air Engines web site shows his work with small compressed air engines. I intended to provide the link in the Introducing AirNergy post, but I couldn't find it. I have now added Mike Smith's link to the "Hands On" section of that post as well.

Problems and Solutions
Of course there are some problems associated with using compressed air for energy storage.
1) High pressure tanks need testing. This might be solved with new tank materials and manufacturing processes, but for now, testing has to be done. Battery banks also need to be replaced periodically. It might also be possible that larger, low pressure tanks would be a more practical solution.
2) The overall efficiency of the system may be low. I don't think this is a big problem if you are using natural sources to compress the air in the first place. Efficiency will also increase as the technology develops. The article, Advantages of compressed air as an energy vector, discusses the efficiency of using compressed air.
3) Tank space might limit the practicality of using compressed air.

Your Turn
If any of you have opinions, ideas, or other problems and solutions, etc., let me know what you think.