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  1. You need to calculate the total peak demand of the specific plug load for a specific area type. Ex: 1W/sf of plug load density for 2,000 sf space. If you multiply the numbers, you get 2,000 W or 2Kw of peak demand for plug loads.

  2. You need to calculate for how many hours your plug loads are turned on. You can calculate it easily by looking at the plug load schedules.

2.1. Calculate the number of hours for weekdays: Simply add the fractions for day (24 hour values) schedule. Ex: 0.1+0.2+0.8+0.9..........+0.4 = 15.5 hours. It means overall, the plug loads are ON for 15.6 hours (Call it A1). Do similar work for the weekends (only if the schedule is different for weekends). Lets say the value is 8 hours (Call is B1) for sat & sunday both.

2.2. Calculate total number of hours in a year when the plug loads are ON. Multiply A1 by total number of weekdays in the year, and B1 by number of weekends. Make sure you exclude the public holidays too (if). There are 260 weekdays in 2017, (15.6260) + (8105) = 4,896 hours out of 8,760.

  1. Multiply 4,896 by 2Kw = 9,792 kWh.

You do exactly same calculations for lighting or any other space loads.