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Generation - Scenario 1

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This post is inspired by Problem 36, Chapter 17 (Power Plant) of "Textbook-Reviewer in Electrical Engineering, 1st Edition" by Professional Electrical Engr. (PEE) Marcialito M. Valenzona.

SITUATION

An existing power plant has a maximum demand of 20MW. With a load factor of 55% and a capacity factor of 50%, what is its present reserve capacity?


ANALYSIS

1.) Average demand:

Load factor is the average demand over the maximum demand for a given operating period.

LF = demand,avg / demand,max
0.55 = demand,avg / 20MW
demand,avg = 20MW * 0.55
demand,avg = 11MW

2.) Maximum capacity:

Capacity factor is the average demand felt by the plant over the plant's maximum installed capacity.

CF = demand,avg / capacity,max
0.5 = 11MW / capacity,max
capacity,max = 11MW / 0.5
capacity,max = 22MW

3.) Reserve capacity:

Reserve capacity is the difference between maximum capacity and maximum demand.

capacity,rsv = capacity,max - demand,max
capacity,rsv = 22MW - 20MW
capacity,rsv = 2MW

CONCLUSION

The present reserve capacity of the power plant is 2 MegaWatts.

Note:

Load factor is different from (but related to) demand factor.

Demand factor is the maximum demand for a given operating period over the total connected load (including those not presently energized).

LF = demand,avg / demand,max
DF = demand,max / load,total

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