JUN 04

Canadian firm Thin Red Line Aerospace is working on the first test deployment of its energy storage system for use with off-shore wind turbines. The Energy Bag provides power storage as "undersea compressed air energy storage" (CAES) to store compressed air deep underwater, and then release it again to drive generators when more power is needed. Storing power for peak load demand or for periods of intermittent wind are an important part of developing a responsive wind generation system that can effectively contribute to the grid at all times.

The process is conceptually straight forward: Wind turbines fill the balloon-like underwater bags with compressed air that later drives electrical generators on demand. While initial application is ideally linked to floating wind turbines, excess electricity from the grid—or from clean energy sources such as tidal and wave power—can also be used to drive compressors to fill the energy bags. The technology is especially suited to countries with relatively deep waters near their coasts.

Instead of engineering a heavy pressure vessel to store large amounts of highly compressed air, the Energy Bag uses a deep water location to serve as the pressure vessel to store the compressed air at extremely high pressures. The prototype Energy Bag itself weighs only 75 kilograms (165 pounds), but is able to displace 40 tons of seawater. It will be located about 600 meters (2000 feet) below the surface, where pressures are 60 to 70 times atmospheric pressure. The power storage in just one bag can be considerable. "At depths of around 600m, there will be enough pressure in one 20m-diameter bag to store around 70MW hours of energy. That’s around the same as 14 hours of energy generation from the largest offshore turbines currently in operation."

The Energy Bag has the potential to be orders of magnitude less expensive than industrial battery storage systems, and even just a fraction of pumped hydro storage systems. Not every location has deepwater locations suitable for this power storage, but several areas in Europe in particular have both good wind potential and deep water close by offshore as potential locations where this could be implemented.

via: Great Lakes Energy News

Comments (8)

Subscribe to this comment's feed

An answer to the baseload argument?
written by Green Living, June 05, 2011

The simplicity of this idea is striking. With a little luck and argument, this just might help to address those that knock the potential for wind energy to provide baseload power levels even in calm weather - an argument I've never really thought was valid.

• 
• +7
• 
• 

...
written by Marcela, June 06, 2011

Simple, eco friendly and with a definitely high positive impact!Wind energy has got an awesome potential!

• 
• +5
• 
• 

Wind Power and Renewable Energy
written by SpareFoot, June 06, 2011

This could be a great step toward a more integrated use of wind energy in the electrical grid. The biggest problem with wind energy, as well as other forms of renewable energy, has been storage.

• 
• +4
• 
• 

What if the bags rupture?, Low-rated comment [Show]

Read the detail story
written by Matt, June 07, 2011

The wind mills dont pressurize the air. Elec powered air comperssors do. This artical isn't about wind, it is about power storage. The full artical also lists using contrete domes underwater and salt domes (cheapest if you got them). Yes there is a chance they could fail, and for that reason you would no place it in a shipping lane. But then again, why would you want to place them there. You know what happen if a LNG ship ruptures all its tanks while in port? Yet we still have a lot of the ships.

• 
• +1
• 
• 

...
written by tom, June 15, 2011

This sounds like you are getting the electricity to run the air compessors for nothing.
You can't create energy!!
IF you use the wind power to run the air compressors you take power away frfom the grid.
Until a way to store electrical energy is designed "Wind POwer will Be A Use it or LOse it Power Supply" and the base power supply will come from conventional power plants.

• 
• -5
• 
• 

Totally ignored when publicised here on Ecogeek last year
written by Glen McDiarmid, June 16, 2011

I posted this exact idea on Ecogeek 16th September 2010 within an article based on a wider use of compressed air:
http://www.ecogeek.org/compone...ticle/3284
The article also detailed massively increased compressed air storage on land or within vehicles in a small package using a different technology:
http://www.ecogeek.org/compone...ticle/3284
All stuff I took to the patent office years ago but didn't have the cash to complete. Good to see someone making money out of it. Pity it's not me Look for the article "Air is yet to make its mark" by Glen McDiarmid.

• 
• +0
• 
• 

This could sink any vessel that is sailing in the water
written by Hugi, June 16, 2011

I very much like the idea and think it is great engineering. I see just one risk. If the bag bursts you are better not sailing in these waters. It could probably sink a whole tanker. As the air rises it will become a huge bubble, approximately sixty times the size of the 20m bag. Therefore you will have to mark the water surface and better move it away from your swimming wind turbines.

• 
• -1
• 
• 

Name

Email

Website

Title

Comment

smaller | bigger

Subscribe via email (registered users only)

Write the displayed characters

Add Comment