Cottonwood Inspired Wind Energy

Cottonwood Inspired Wind Energy

Three 150-foot-plus tall cottonwood trees tower over and dwarf my ranch-style home.  From across the lake, I can always spot my house, as these trees are some of the tallest on my lake.  Every spring sticky pods bearing a yellowish sap fall to the ground.  These pods cover the patio, cars, and furniture with its difficult-to-remove substance; soap and water just don't suffice.  A pod trail meanders through my house and upon my car’s floor mats after attaching to shoes, socks and my dog, Cheetah’s paws.  In early summer, seeds wrapped in a fluffy cotton-like material create a winter-like snowfall.  I even use a snow shovel to clean them from my driveway.  These seeds will sprout at the slightest contact with moisture.  If I fail to blow these droppings from my landscape mulch, I will awake to a green carpet of sprouts on a dewy morning.

My neighbor hints to removing these “messy trees” but Nature proves there is success from the appearance of chaos.  Obvious wins include oxygen, beauty, and a shaded house during the intense summer heat.  My air conditioning rarely starts before mid-July.  Living along a lake, means a wet yard after rainstorms, enough so that ducks will be swimming on it.  Near these water-loving trees, however, dryness prevails.  Surprisingly, an arthritis soothing balm, called Balm of Gilead, can be made from the pods[1].  I have also always wondered if the cotton I collect with my snow shovel can be spun into yarn and sure enough it sells for about $0.07 per yard[2].  

At Cornell University, the cottonwood trees' leaves have inspired a small-scale energy generator[3,4].  An array of foam blocks, each suspended on its own cantilever beam, will vibrate in the wind like the leaves on the cottonwood branches (watch video).  Each beam contains a piezoelectric transducer, which is a ceramic substance that creates electricity when deformed.  Each block of the array provides a cumulative energy gain even at low wind speeds.  These arrays can be mounted on buildings or other areas where a wind turbine isn't ideal.

Take 10 minutes today to get outside and explore how “Nature Comes Standard” in your life.