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.
Elon Musk made headlines around the world this summer when he lifted the curtain on the "hyperloop" -- a concept for an ultra-fast train that could transport passengers at speeds of 600 MPH. Now a team of engineers has announced plans to build a working hyperloop prototype by next year. Musk isn't behind the plan, but his company Tesla made a couple of major announcements this week. First, Tesla bought nearly 2 billion Panasonic lithium-ion battery cells. Then, the electric carmaker completed a network of electric vehicle charging stations stretching all the way from San Diego to Vancouver. While hyperloop talk is speeding up, bikes are continuing to grow in popularity -- more bikes were sold than cars in 23 European countries last year, proving that you don't have to reinvent the wheel to go green. On the other hand, reinventing the wheel is exactly what design student Ackeem Ngwenya did when he created a shape-shifting tire that can adapt to different vehicle types and road conditions. In other global transportation news, Turkey unveiled the world's first intercontinental underwater rail tunnel, linking the European and Asian sides of Istanbul. And at the 6th Annual US-China Transportation Forum, Chinese officials announced that they are expanding their nationwide network of highways, railways and airports, while the US federal government struggles to maintain the country's crumbling infrastructure.