Why generate 500 MW when you can step up & step down ?

Replies

• 

  grsalvi

  As far as i know after power is produced by generators ,it is stepped up at generating station and transmitted.
  
  Why there is need to step down to 'x'Mw ? Can you give a link or text where you came across this.
  
  One of the reason why high rating generators are used is 'efficiency'.
  Its completely separate concept which involves calculations based on load flow diagrams , type of plant ,etc.
  Based upon these calculation the rating of generators are decided to get optimum performance.
  Usually calculations result into high ratings and hence high rating generators are used.
• 

  lal

  In fact we cannot step-up or step-down power. It is always a constant which is equal to the generated power(neglecting all loses). All we do is to change the magnitude of voltage using transformers. But, if we change the volatage, the current also varies. Because
  Power = Voltage x Current
  
  The maximum generated voltage in India is 11KV. Since most generating stations are all located in remote places, the power generated has to travel a lot of distance to reach the civilisation and industries. The problem here is, if 11KV at 500MVA is transmitted for such long distances, the transmission losses will be very high. So this voltage is stepped up to 33KV, 66KV or even 132KV. As the voltage increases, the current decreases (P=VI) because power is constant. Doing so, we can reduce the transmission losses and achieve very long distance transmission. At the end of transmission is the distribution network where this high voltage is stepped down for industrial and house hold uses.
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  Jeffrey Arulraj

  Well with out input how on earth or you planning to modify it?
  
  You need input which is got from generators. Then only we can do any modifications to it both step up or down
• 

  lal

  Let me ask a question first. How can someone step-up or step-down power? MW is the unit of power. Did I miss anything in my college or was I sleeping during that topic! 😲
• 

  grsalvi

  lal

  Let me ask a question first. How can someone step-up or step-down power? MW is the unit of power. Did I miss anything in my college or was I sleeping during that topic! 😲

  Yes you are very correct you cant step down or step up power.All we can do is stepping up of voltage or current.
  I wrote power is generated by generator and it is stepped up .This explicitly means stepping up of voltage / current (again current is not there as its sending end station).
  Just wrote in short form as any electrical engineer knows this.
  
  Now writing voltage is generated in generator sounds wrong (as induced is correct term).
  
  Anyways, i correct it
  "
  As far as i know after power is produced by generators ,voltage associated with that power is stepped up at generating station and is transmitted ".
  
  Now buddy please dont say that in above line i said voltage is transmitted (its power ).
  
  Take note of correction please #-Link-Snipped-#
  😉
• 

  lal

  😁 I didn't get those explicit points there. I was reading along what was written there. So I guess sandy also meant about voltage explicitly. And power cannot be stepped down to 'X MW', implicitly or explicitly.
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  Jeffrey Arulraj

  All seems cool till we plan on what we are doing with the output power ?
  
  If it is for transmission Voltage better be stepped up if for consumption Current has to be stepped up That will be it I guess I am right
• 

  solar morpher

  sssssandy

  If the output of a generator is 500MW then it is stepped down to some 'x'MW for transmision purpose and then stepped up where required. my qustn is wat is the need to generate 500 MW, can we generate only 'x'MW and stepup where req.

  Power is not generated my buddy only a potential difference is built up in a generator in no load.
  
  When a load is put in between these potential difference power is said to be transferred and thus the term power generation.
  
  Now when looking at voltage generation Very high voltage cannot be induced economically in a single place as this is destructive. And so we generate a potential which our design can handle. Then we put a load to get powered by this potential. Next we place the transformers to do the final magic to transmit power to load centers.