In a grassy clearing, well-heads, buildings and pipelines cover a few acres. On the other side of the world, hundreds of acres of earth are upended by draglines and transported by huge dump trucks. Despite the contrast, both sites are accomplishing almost the same thing. At the first site, an underground coal gasification project in Australia, coal is burned in place and the resulting gas used to generate electricity or converted into diesel. The other site is a coal mine in the Powder River Basin of Wyoming and Montana — a region that could soon see more operations like the Australian one. Underground coal gasification (UCG) is one of a handful of techniques being tested across the West to make coal — the cheapest, most plentiful fuel around — more palatable to a carbon-constrained world. Researchers are also trying to capture and sequester carbon from conventional coal plants, and