Eric Osborne sez:

OK, let's see if we can turn this thread from BBN-bashing into something a bit more constructive. I've seen several posts in the past few days concerning optimal power backup strategies, both short and long term (battery, diesel, and/or nuclear). Anybody out there care to share your strategies?

Putting on my EE hat: 48vdc string, everything running off it is the #1 best answer from reliability. Time proven by THE paranoid folks in the world, Bell System Practices. But the initial expense, space, weight, safety aspects, ventilation; all make this unlikely for anything except a tariff-funded CO. And it need generators. You can not really store many hours of energy in oxides of lead; it just costs too much. [Last time I asked, RBOC CO's had several hours worth of battery; in theory long enough to get a semi-mounted unit there if the local generator fails.] That takes us back to UPSi on equipment, and generators. Technologies available are: Gasoline engine -- used for smallest. Mucho fire code hassles. Diesel. The old-line standby. Fuel is much safer to store, but needs tending. The block must be kept heated in cold climates if you want it to start. All sizes - Cat makes 'em as big as you want -- I've helped tend a pair of 600kw units in a third world county.... Gas Turbine. Not very fuel-efficient, but much less routine maint than Diesels. Also smaller. variations: Propane fuel Natural Gas All share the same hassles to some extent or another. They have to be run, UNDER LOAD, an hour+ per month. They need the oil changed. They need clean fuel; #2 Diesel tends to grow weird bugs that clog the filters. The propane and natural gas can feed modified gasoline piston engines and turbines. Some Diesels run on a fix of #2 and gases. [The ultimate example -- a sewage plant will recover sewer gas and use it w/Diesel. If your userbase is full of BS; or your tie curls and your boss has 2 horns, you might go this route...] Natural gas has advantages of no storage hassles; propane does not go stale. In short, they all need tending. Regularly. As for installing, there are a million details. Ventilation. Fire codes. Noise & Neighbors. Floor loading. Power transfer. Load segregation [what is, and what's NOT, an emergency load...] Hire an engineering fire with experience in your locale -- this is not a task for anything less. -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close........[v].(301) 56-LINUX Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433