🚀 go-pugleaf

 In talking about synching power generators with a grid, about 
 a year ago, I lead an IEEE student group tour down to the Childs
 hydro power plant (central Az).  This is very interesting since
 it was one of the first plants operating in Az (and the oldest still
 on line).  You go look at the equipment, and much of it is dated
 1890 or 1905.  

 Anyway, it is a very small operation, about 500kw run from a small
 resevoir fed by springs.  If I remember correctly there is about
 300' of head.  When it was first brought online, they said it 
 supplied all the needs of Northern Arizona, and half of Phoenix!

 I was suprised to learn when the plant was shut down that they didn't
 disconnect from the grid (for example, to clean the pipes and
 turbine valves).  They just let the grid power the generators as 
 large electric motors.  Said it was a whole lot easier than trying
 to bring them up from a dead stop and re-synch them to the grid
 (which had to be done by hand).  They had the original Westinghouse
 synch-meter which was about the size of a wall clock.  It as
 (was) calibrated in + and - degrees, with a big crank to make
 speed adjustments.  The tech on duty indicated that he was there
 once when someone goofed and put the plant on line with a 3 degree
 difference.  He said it sounded like a cannon going off and 
 shook the whole building. Didn't do any damage though.  

 I found it suprising that it was still economical to operate a 
 plant of this size.  But basically the capital expense was paid
 off long ago, the equipment doesn't wear out very fast, and it only
 takes a couple of guys to run it.  Mainly they just have to keep 
 watch on the resevoir water level to make sure it doesn't get 
 too low.

 It was nice for the students as well since all of the equipment
 is open-frame, and you can see the rotors going 'round and so forth
 since there aren't any covers.  REALLY noisy, though.


 - Bob Wier

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                      College of Engineering
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