Great idea, but how about working with reflected light rather than setting up more energy-use requirements? The Brits fooled the world in World War II with their use of reflected light and mirrors, obscuring the Suez Canal..I hope we can do even better now, fifty years later.
Community gardens are always good – in Philly my block had reclaimed a lot, moving the debris by hand, brick by brick, finally winning awards with our little 8×8 vegetable plots..And of course, with vacant buildings, I always loved the ‘turn the building into a washing machine’ look, with painted socks floating in the windows.