Energy in a Bottle

In class, we have talked a bit about the use of wind power as an alternative energy source, and we discuss its pros and cons. We discuss how it can be used to decrease the consumption of oil, gas, and coal, and research is always in progress to make wind power a more prominent form of energy in our everyday lives. But what would you say if you heard that wind power can actually bring life?
As crazy as that sounds, a Dutch artist named Theo Jansen has been working for the past 16 years to create a new breed of animals. His goal is to create a species of “animals” that can live and roam on a beach and even survive the forces of nature. The way he presents his creations makes him seem a little insane, but his creations, in a way, do have minds of their own. (A video of Theo Jansen’s creations is at http://www.ted.com/index.php/talks/theo_jansen_creates_new_creatures.html)
How Jansen accomplishes this seemingly impossible task of giving life is what is most interesting. The creatures have a basic structure made up of plastic tubes. These tubes are proportionally configured to create legs. The configuration creates a similar effect of a wheel in that the axes remains level at all times. With this being said, the source of life for this creature is the wind. Wings that are attached to the creature flap in the wind. The energy taken from the wind is what makes the creature walk by rotating a crank-like shaft. To attain the most energy, it turns its nose into the wind. But what happens when there’s no wind?
When the wind dies down, the motion energy comes from lemonade bottles that store up pressure. The creature is made up of tubes and bottles that take the excess energy taken from the wind and keep it in these lemonade bottles. Not only do these bottles keep and give energy, but they also allow the creatures to avoid going into the ocean and “drowning”. The inability of the bottles to suck in air makes it aware that it is in the water.
Even though I told you about all the details of the creatures (because they are so cool), the main purpose is to make people aware of the versatility of wind power. An issue of wind power is that it is only useful when there is wind. In Jansen’s world, the lemonade bottles stored the energy to keep the creatures alive. That is very small scale energy storage, but how can we store wind power at large scales?
At Iowa Stored Energy Park, researchers have developed a method to create large scale “lemonade bottles”. These storage units are located thousands of feet underground. From the windmill farms, excess energy can be stored in underground sandstone layers. The sandstone works like a giant balloon, and layers of shale above the sandstone keep the air from seeping up. The excess energy runs compressors that send the air 3,000 feet below the surface into the sandstone. When the area is in need of more energy during peak hours, the air pressure is released back up the pipes to the natural-gas turbines to increase the efficiency. A diagram illustrates the system can be found at http://images.businessweek.com/ss/07/09/0927_windpower/index_01.htm. With this form of energy storage, peak consumption times can be controlled and energy lost as excess can be avoided.