>> Someone mentioned Bell using jet engines for central office power
>> backup. I'm kind of surprised at this. The electric companies use
>> them for summer supplements. They are very expensive to run, but can
>> get up to speed very quickly. I believe the phone companies use more
>> conventional diesel engines to power generators. If there is a power
>> failure, central office battery has enough capacity to keep things
>> going for a while, more than enough time to power up a diesel engine.
>> The jet engine has the advantage of being smaller.)
> Every "emergency engine" I ever saw in a telephone building was a
> conventional diesel engine. My father-in-law was shop foreman for a
> company that sold and service large earth moving equipment in Enid,
> Oklahoma, and from time to time they were called upon to routine the
> auto-start emergency engine in the Enid c.o. It was a conventional GM
> diesel engine like those used on earth moving equipment and
> locomotives.
SBC (Pacific Bell) Canoga Park CA had an International Harvester Solar gas turbine power plant on the roof for many years -- since it needed to be on the roof to conserve ground-level space for parking, they needed something light and small. Personally confirmed during a long ago Open House.
I think it's still up there, but I haven't driven by the CO during a test run or power failure for many years. Sounds exactly like a jet helicopter parked on the roof at idle (muffled as much as practical) and it takes the turbine a good 30 seconds to spool up to speed and take the load. But since the switching equipment is on the battery plant, the extra delay was not a problem.
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