Each week our friends at Inhabitat recap the week's most interesting green developments and clean tech news for us -- it's the Week in Green.
It's difficult to think about winter in the middle of a very hot summer, but if you live in Norway, winter never seems too far off. There, engineers have come up with a creative solution for the lack of winter sunlight by setting up a cluster of large mirrors to direct natural light toward the town of Rjukan, which sits in a valley. In the US, scientists are developing new techniques to harvest the power of the sun, as a team of researchers from the University of Maryland has developed a long-lasting battery that's made from wood. 3D printers are capable of amazing feats, but a new study finds they release a high amount of ultrafine particles into the air, which can be harmful if inhaled. Star Wars fans will be saddened to learn that migrating dunes in Tunisia are threatening to destroy one of the most famous filming locations captured in Star Wars Episode I: The Phantom Menace. And in the week's most inexplicable example of environmental destruction, the US military dropped four bombs on the Great Barrier Reef as part of a training exercise.