Load Factor Formula
Load factor (LF) is defined as the ratio of average load to the maximum demand for a given period of time. Just like demand factor, the load factor is smaller than 1. LF can be defined on the basis of daily, monthly or yearly basis.
Load factor formulas
List of Formulas 

Load factor =
Average load
/
Maximum demand

LF =
Units generated in time t (hours)
/
Maximum demand * t hours

Daily LF =
Units generated in day
/
Maximum demand * 24 hours

Monthly LF =
Units generated in month
/
Maximum demand * 720 hours

Yearly LF =
Units generated in 1 year
/
Maximum demand * 8760 hours

where
1 day = 24 hours
1 month = 720 hours
1 year = 8760 hours
Calculation Examples
Daily LF is a ratio of units generated in a day to MD * 24 hours.
Example 1: The average load (AL) on a certain coal powered station is 3 MW. The MD is 5 MW. Find the LF.
Solution: LF = AL/MD = 3 / 5 = 0.6 = 60%
Example 2: The maximum demand on a thermal power station is 20 MW. The station generates 312 MW in 24 hours. Find the daily LF
Solution: Daily LF = [312 MW]/[20 MW * 24 hours] = 0.65 or 65%
Annual load factor is defined as the units generated per year to maximum demand.
Example 3: A nuclear power station has MD of 50 MW. The station generates 300 * 10^{6} kWh annually. Calculate the load factor.
Solution: 300 * 10^{6} kWh = 300 * 10^{3} kWh
LF = [300 * 10^{3}]/[50 MW * 8760] = 0.68 = 68%