Reuters: Australian mining firms, hit by high fuel costs and falling commodity prices, could soon swap their diesel generators for 24-hour, solar-power systems, the head of a private renewable power firm said on Thursday. Mining firms are also worried about an emissions trading scheme set to begin in Australia in 2010, Steve Hollis, CEO of Sydney-based Lloyd Energy Storage, told Reuters in an interview. The emissions scheme will target the top 1,000 polluters and mining firms. Many of …