Coal can be a dirty word in the United States but according to this article in the Wall Street Journal the rest of the world will use more and more of this commodity to produce power in the future. According to this article China produces almost 2/3rds of their electricity from coal. So investments in coal in non U.S. companies might be attractive. Of course investing in non U.S. companies can be more risky. Read this article in the Wall Street Journal to see what you want to do.