Question

The maximum demand of a power station is 100 MW. If the annual load factor is 40%. Calculate the total energy generated in a year:
1. 3.5 × 10⁵ kWh
2. 3504 × 10⁵ kWh
3. 3504 × 10⁶ kWh
4. None of these

Answer 1

Correct Answer - Option 2 : 3504 × 10⁵ kWh

Concept:

Load factor (LF): 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

\(Lf = \dfrac{{AL× T}}{{MD × T}}\)

\(\rm = \dfrac{{Units\;generated\;in\;T\;hours}}{{Maximum\;demand × T}}\)

Where LF is Load Factor, MD is Maximum Demand, AL is Average Load.

• The load factor may be daily load factor, monthly or annually if the period considered is a day or month or year
• 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, it 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.

Calculation:

Given that, maximum demand (MD) = 100 MW

Annual load factor (LF) = 40% = 0.4

\(0.4 = \dfrac{E}{{100 × 10^6 × 365 × 24}}\)

E = 3504 × 10 ⁵ kWh