Here are a couple of stunning entries from Italy's Solar Park South design competition, which sought environmentally-friendly proposals that could be integrated into the Salerno-Reggio Calabria highway.
The winning entry (from the French quartet of Philippe Rizzotti, Vermet Tanguy, Manal Rachdi, and Samuel Nageotte) proposed a "vertical village" built into one of the highway's bridge structures in a volcanically active area. Geothermal power would provide juice for inhabitants, and the verticality of the structures would provide a good use of what's normally dead space occupied by pilings. Large horizontal decks would provide both public space and a means of capturing rainwater.
Second Prize (from the Italian trio of Francesco Colarossi, Giovanna Saracino, and Luisa Saracino) ain't too shabby either; the proposal calls for a bridge that taps both solar and wind power, the former from the roadway and the latter from the pilings. I absolutely love this design because it's the first time I've seen a wind farm that had some serendipity to it, incorporating a very Italian way of bringing beauty to what would otherwise be a boring-looking industrial scheme.
What Third Prize (not pictured here, and from Colombian quartet Daniel Azuero, Tomas Jaramillo, Andres Gutierrez, and Juan Jaramillo) lacks in compelling images, they make up for with a thesis we can get behind:
Among all known renewable energies the most efficient and the only one of its kind capable of regenerating infinitely producing "zero environmental harm" is EDUCATION. This type of energy is an inexhaustible supply of knowledge that spreads from person to person covering vast extensions of area resulting in massive social, environmental and economical progress.