Correct Answer - Option 4 : Load factor
Load factor: The ratio of average load to the maximum demand during a given period is known as the load factor.
Load factor = average load/maximum demand
If the plant is in the operation for T hours
\(Load\;factor = \frac{{Avearge\;load \times T}}{{Maximum\;demand \times T}}\)
\(= \frac{{Units\;generated\;in\;T\;hours}}{{Maximum\;demand \times T}}\)
- The load factor may be daily load factor, monthly or annually if the period considered is a day or month, or year.
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The load factor is always less than 1 because the average load is smaller than the maximum demand.
- It plays a key role in determining the overall cost per unit generated.
- The higher the load factor of the power station, the lesser will be the cost per unit generated, is because a higher load factor means lesser maximum demand.
- The station capacity is so selected that it must meet the maximum demand.
- Now, lower maximum demand means a lower capacity of the plant which reduces the cost of the plant.
Diversity factor: The ratio of the sum of individual maximum demands to the maximum demand on the power station is known as a diversity factor.
\(Diversity\;factor = \frac{{Sum\;of\;individual\;maximum\;demands}}{{Maximum\;demand\;on\;power\;station}}\)
A power station supplies load to various types of consumers whose maximum demands generally do not occur at the same time. Therefore, maximum demand on the power station is always less than the sum of individual maximum demands of the consumer. Hence diversity factor is always greater than 1.
Plant capacity factor (P.C.F.):
It is the ratio of actual energy produced to the maximum possible energy that could have been produced during a given period.
P.C.F. \( = \frac{{Average\;demand × T}}{{Plant\;capacity × 100}}\)
P.C.F. \(= \frac{{Average\;demand}}{{Plant\;capacity}}\)
\(Annual\;plant\;capacity\;factor = \frac{{{\rm{Annual\;kWh\;output}}}}{{Plant\;capacity × 8760}}\)
Utilization factor: It is the ratio of maximum demand on the power station to the rated capacity of the power station.
Utilization factor = maximum demand / rated capacity
