1sockchuck writes: Data centers operators often tout their diesel backup generators as a symbol of their reliability. So why does Microsoft want to get rid of them? Microsoft says diesel generators are "inefficient and costly" and is looking at alternatives to supply emergency backup power for its server farms, including fuel cells powered by natural gas. One possible option is the "Bloom box," which both Apple and eBay are using in their data centers (albeit with biogas as the primary fuel). Bloom is positioning its fuel cells as a way to forego expensive UPS units and generators, using the Bloom box for primary power and the utility grid for backup. It's a pitch that benefits from the current low price of natural gas.