At 05:01 PM 4/4/2003 -0800, Bill Woodcock <woody@pch.net> wrote:
4) In larger sizes, Diesel gensets are _cheap_.
The only difference between the diesel and gas genset is the carburetor, which is just different, not more expensive.
Not entirely accurate. Since has low volumetric energy density compared to diesel, NG/Propane gensets are basically de-rated diesel gensets. A 150KW diesel would be approximately 100KW as a NG and slightly less than that when running on propane. There is an interesting research/marketing paper from Onan/Cummings on current and emerging power generation methods including diesel, ng, propane, hydrogen, turbines, reciprocating engines, microturbines, and fuel cells. http://electrochem.cwru.edu/yeager/ohiofuelcell/Norrick-Cummins.pdf When I was evaluating gensets for our datacenter, I found a really interesting unit which uses propane and/or natural gas mixed with the air to extend the runtime by adding significant BTUs from the gas. However, it can run directly on diesel alone should the gas supply be interrupted for some reason. Very neat technology and obvious after the fact, but much more expensive. We opted for a standard diesel genset since it is reliable and proven. The last thing I wanted was unknowns in a energy source I need to depend on when everything else goes to hell. -Robert Tellurian Networks - The Ultimate Internet Connection http://www.tellurian.com | 888-TELLURIAN | 973-300-9211 "Good will, like a good name, is got by many actions, and lost by one." - Francis Jeffrey