At 02:34 PM 9/16/2001 -0700, Sean Donelan wrote:
On Sun, 16 September 2001, kevin pop account wrote:
Before someone asks we have a very steady national supply over here so running the gens is purely a commerical aim.I would have thought that even stateside this would make sense no ?
The US has fairly strict air quality control laws. It is relatively expensive to operate a desiel generator more than 100-200 hours a year in a major urban area due to the permits and environmental pollution control requirements.
You should remember that generators are mechanical devices. Wear and tear during extended run-times *WILL* result in breakdowns. The longer your operate the generators, the more failures you will experience. Its always a trade-off between how long you test mechanical equipment. Based on DOE studies, many people actually over-test their backup generators.
Standard Bell telephone CO design doesn't assume extended disasters. Some colocation facility designers have designed their generator plants differently than normal Bell practice. But even colocation facility operations need to set some limits to their design conditions.
In our new datacenter in Newton, NJ, we are in the process of getting RFPs to install Capstone micro turbines for backup power. They are DESIGNED to run for 8,000 hours before the first maintenance is needed. At 333 days (8k hours) an airfilter should be changed. They can run for 60 months 24/7 before a rebuild is needed. They need a tuneup kit at 24 and 48 months (assuming 24/7 service) at a cost of $2700 per service. They are impressive units, but... 1. They give off extreme amounts of heat (which can be used to heat your building), 2. they rely on natural or LP gas. 3. they are VERY expensive compared to diesel gensets - 2-4 times as much per Kw! A 60kW unit costs $69,775 A 28kW unit is $45,582. They can be ganged together to provide N+1 redundancy and load sharing. http://www.capstoneturbine.com I have no financial interest in the company, but they seem to be the only game in town with a unit with EXTREME runtimes. Does anyone else use these at their datacenter(s)? -Robert Tellurian Networks - The Ultimate Internet Connection http://www.tellurian.com | 888-TELLURIAN | 973-300-9211 "It is never too late to be what you might have been." -George Eliot