Cool Earth’s Solar Balloon
Cool Earth’s inflated solar concentrators may be the lightest power plants around. Looking like a biggie version of those shiny helium balloons you might see at someone’s birthday party, the concentrators weigh just 20 pounds and, tethered to lightweight aluminum towers, seem to float 20 feet off the ground gathering solar energy. Able to withstand winds up to 125 mph, the 8-foot-wide Mylar balloons are reflective on one side, and each one has its own lightweight tether.
Ultimately, the company would like to get the cost down to $1 per watt, and with each balloon generating up to 500 watts, more than enough to run your 50-inch plasma TV. The average home uses between 1 and 2 kilowatts keeping your beer cold, your water hot and your Guitar Hero performances lukewarm, so if you had a big enough backyard and forgiving neighbors, you could run your home off just a few balloons. But Cool Earth is targeting utility-scale projects and plans to have its first one up and running in Livermore, CA, this fall.