BBC: Texan cattle rancher Mike Baca seems an unlikely evangelist for the American green revolution. When he voices a visceral dislike of the “Washington liberals” there seems to be little hint of the environmentalist beneath the cowboy hat and saucer-sized belt-buckle. But Mike is proof that renewable energy now unites the partisan debate on climate change. Many Republicans sceptical of climate science support a major expansion of renewables to ease their nation’s dependence …