Geothermal has long been hyped as the next big thing in renewable energy, but its breakthrough moment hasn’t happened yet. Barriers to expansion include the elusiveness of sites offering the magic trio of heat, water and permeability and concern for unique ecosystems. Contributor Jessica McKenzie on geothermal energy’s possibilities and challenges and the government funding that may finally fire it up.

When humans began to put down roots, we also started to forge what Giulio Boccaletti calls a “social contract” with water. In his new book, “Water: A Biography,” the London-based scientist explores that relationship through a long historical lens. BookShelf contributor Gary Wilson reviews the volume and finds that political ambitions and economic development are central to the story.

Under federal rules, states can decide whether to divulge information about hazardous materials rolling along their railways — and mostly they don’t. Not knowing where and when hazmat trains are traveling or what’s on board creates anxiety and raises the risk for those who live near the tracks. TipSheet offers resources and step-by-step instructions for investigating railway hazmat threats to your community.