Why only "even" number of Generating Units in Power Station? 6

[starwhizz]

So far, I have seen mostly odd number of Units in Hydro Power stations. Why does the designer choose only "even" number of units?? What is the disadvantage of having "odd" number of units??

I would appreciate some answers.

Thanks

 

[byrdj]

how about why horizonal CCW rotating units should be aligned e-w, where CW units are w-e, except if aligned n-s, which should be avoided if possible (applicable to northern hemisphere)

 

[waross]

Years ago, a numerologist on the crew unintentionally entertained us. I wonder what the numerologically optimum number of sets would be.
As for AC versus DC, I guess that it depends on your personality. DC is steady and dependable but most designers seem to want more excitement and go for the peaks and valleys of AC.
(I'm starting to enjoy the new medication.)

Bill
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"Why not the best?"
Jimmy Carter

 

[waross]

Should verticle sets rotate with the earth's direction of rotation or in opposition to the earth's rotation? May there be adverse long term affects to the inclination of the earth's axis if the net rotating mass becomes too great in either direction?
Enquiring minds want to know!!

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Skogsgurra]

I must say that, given all the possible combinations, it is a miracle that we have power stations at all! How could the designers make up their minds? And we have not even started to consider things like colour of the machinery.

It boggles the mind.

Gunnar Englund

http://www.gke.org

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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[rmw]

I still have the color pattern selection page from one of my first power plant start-ups. The lead engineer couldn't decide on the colors so he told his wife to pick them. She cut color blocks from a magazine and pasted them to a sheet of paper, and lo and behold, the gas turbine was one color, the steam turbine another, the generator yet another and the (axial flow above grade condenser) was deep blue.

It was an odd assortment of colors, and somewhat feminine, I thought, soft pastels except for the deep blue condenser, but that is what she picked, and what we painted them.

Now, when it comes to E-W vs N-S, I have observed unscientifically over a long period of time that N-S oriented solid fuel boilers with wear particles in the flue gasses have heavier wear weighted to the west side of the parts of the units subject to wear where E-W oriented units have essentially even wear. Coriolis effect???? Make up your own mind. A very small percentage of a lot of particles thrown to the Coriolis reaction side of the gas passes could add up.

http://en.wikipedia.org/wiki/Coriolis_effect

I can't say whether or not that is the case, but I do know that if I ever had to site my own unit, I know which direction it would face.

rmw

 

[darai]

Look all around you:
2 hands, 2 feet, 2 eyes
male occurs with female = gettting even
negative occurs with positive = 2 or 0, all is well whichever way you take it
Guess the universe is in harmony only when everything works out even
see, good and evil = 0, in nothingness is calm!

 

[burnt2x]

Look all around you:
2 hands, 2 feet, 2 eyes
male occurs with female = getting even
negative occurs with positive = 2 or 0, all is well whichever way you take it
Guess the universe is in harmony only when everything works out even
see, good and evil = 0, in nothingness is calm!

Darai, dichotomizing sometimes simplifies things, but I think it's not even close to the realities!
Flexibility requirement is and always will be the main criterion for any plant designer. As posted by others, the "what if" one unit conks out?, demand rises above the capacity of one unit?, etc. . will have to be answered by the decision-makers!
Having said that, it's not only the number of units that comes into the equation but also the size of each unit, the expected demand at different times of the day, as well as the seasonal demand profile of the load served. Still, the bottom line will be how deep the pockets of the proponents have.
Respectfully.

 

[zonal]

Thank you everyone! I am sorry about the mess up between "odd" and "even". I tried to log in to edit the post, but i was not able to log in as "starwhizz". I always face problem with log in!

I got my answers. And I am glad my Q provided some amusement to you all.

 

[Skogsgurra]

I had a look at your stats. It appears that this was your first posting in Eng-Tips. Please come back with more 'interesting' questions. We (at least me) liked this.

Gunnar Englund

http://www.gke.org

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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[NAZ55]

darai,
how about a tongue, a forehead, a nose, a brain. Last time I checked I only had one of each!

 

[NAZ55]

Oh by the way, being one of the chemical folks I figured you would know a thing or two about entropy.

 

[ScottyUK]

Some visitors here only have three of the four components you listed...


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