Stepping onto the campus of Iowa State University, you can't help but notice the impressive ancient trees, the dignified brick and stone buildings, the flawless work of what seems like hundreds of groundskeepers, and, if you care about the environment, the enormous energy plant lurking on the edge of it all, a big smog-belching monster. Iowa State University offers a PhD in wind energy and dominates academic research in biofuels, but running the university depends on coal, the dirtiest energy source on the planet. Our power plant is ten stories tall, and emissions float over our campus twenty-four hours a day; yet, amazingly, it might as well be invisible, because many on campus-students, staff, and faculty alike-are virtually incapable of seeing it.