OK, so like a dope I fell for it, and submitted an idea I had to the GE Ecoimagination Challenge.
The first thing I should have noticed was that the input form required the upload of supporting images, zip files, or documents... it wasn't optional. They wanted SOMETHING, ANYTHING uploaded that you might have to back up your idea.
The second thing I should have noticed is that you have to sign away your rights to any interest you had in the idea. That is, they didn't want just ideas, they want inventors to donate the effort they had already made. In effect, GE is promising to generously reward a select few inventors, but they get to peruse and use any of the other ideas submitted freely.
That's a great racket, especially when you are such a politically well-connected mega company as GE. So rather than donate this idea to GE, I'll post it here for everyone to consider:
A house bra shields existing homes from extremes of heat, much like the way a truck bra shields it from debris. A laminate of metalized film and insulating backing will enhance the seasonal energy efficiency of existing structures without costly retrofitting.
There are many, many homes and businesses for which increasing insulation is not an option. For these, an externally applied wrap may be a way to substantially decrease the heat gain due to solar radiation. One application is as an insulating laminate of metalized film and closed cell foam backing. Another would utilize a sandwich of wick materials, in which capillary action draws water up from rain collection tanks, providing evaporative cooling.