Under the right conditions, trains can be the most sustainable form of transportation. Now there’s a new kind of rail tie that makes trains even more sustainable. The company is making the rail is called Greenrail and their railroad tie is more durable than current concrete ties, by upwards of 30 percent, and made from recycled material. Greenrail’s ties also generate electricity as the train runs over them, making them even more appealing to the developing world. The ties are already patented in 148 countries and could have great implications for the developing world.