PREPA's Central Palo Seco power station in San Juan, Puerto Rico. The utility's bondholders want to raise rates. That's a challenge when the median income is about half that of Mississippi, yet the U.S. territory's energy costs are among the highest in the nation.
Oil pump jacks in Williston, N.D., in December. Oil prices have been on the rise, but some analysts say the global economic slowdown, fracking and the rise of alternative energy will mean less demand and lower prices.
Austin Holland, research seismologist at the Oklahoma Geological Survey, gestures to a chart of Oklahoma earthquakes in June 2014 as he talks about recent earthquake activity at his offices at the University of Oklahoma in Norman, Okla. The state had three times as many earthquakes as California last year.