A battle royale between competing visions for the future of energy blew open today on the pages of a venerable science journal. The conflict pits 21 climate and power system experts against Stanford University civil and environmental engineer Mark Jacobson and his vision of a world fuelled 100 percent by renewable solar, wind, and hydroelectric energy. The criticism of his “wind, water and sun” solution and an unapologetic rebuttal from Jacobson and three Stanford colleagues appear today in the Proceedings of the National Academy of Sciences. In fact, while both sides claim to be objectively weighing the energy options, the arguments and backgrounds of the protagonists belie well-informed affinities for various energy sources (and informed biases against others). As sociologists of science would say, their choice of data and their reading of it reflects hunches, values, and priorities.