FORMULA FOR ESTIMATING ENERGY CONSUMPTION

Discussion in 'First Time Marijuana Growers' started by Judge Dredd, Jan 24, 2014.

  1. #1 Judge Dredd, Jan 24, 2014
    Last edited by a moderator: Jan 24, 2014
    If you're new to indoor growing, you may want to read up. Don't be stupid. Don't get in over your head with utility bills. Never assume you know how much your grow room is going to cost.
     
    Use this formula to estimate the cost of your lights (can be applied to anything that draws electricity):

    (watts x hours per day) / 1000 = daily kilowatt-hour (kWh)
     
    1 kilowattkW = 1000 watts (W)
     
    Once you've determined the daily cost to run the lights, multiply it by the number of days you run them during the year.
     
    Example: My 2400W grow tent (4 x 600W):
     
    VEGETATIVE PHASE
    (2400W x 18 hours per day) / 1000 = 43.2 kWh per day
     
    If I veg for 4 weeks, that's 28 days. 1 month out of every 3 translates to 4 months per year.
     
    28 x 4 = 112
     
    43.2 kWh per day x 112 days per year = 4838.4 kWh per year
     
    4838.4 kWh per year / 4 months per year = 1209.6 kWh per month
     
    BLOOM PHASE
    (2400W x 12 hours per day) / 1000 = 28.8 kWh per day
     
    If I flower for 8 weeks, that's 56 days. 2 out of every 3 months translates to 8 months per year.
     
    56 x 4 = 224
     
    28.8 kWh per day x 224 days per year = 6451.2 kWh per year
     
    6451.2 kWh per year / 8 months per year = 806.4 kWh per month
     
     
    Now that you've determined the monthly cost of both the veg and bloom phases, you need to find out what your utility provider's monthly fee is. You also need to find out their rate per kWh.
     
    Mine: $20.08 / month + 10.05 Â¢/kWh
     
    VEG PHASE
    1209.6 kWh x 10.05 Â¢/kWh = 12156.48 Â¢/kWh
     
    Divide by 100.
     
    12156.48 / 100 = 121.56
     
    Now add their monthly fee.
     
    121. 56 + 20.08 = 141.64
     
    This is the dollar amount it will cost me per month during my veg phase.
     
    BLOOM PHASE
    806.4 kWh x 10.05 Â¢/kWh = 8104.32
     
    8104.32 / 100 = 81.04
     
    81.04 + 20.80 = 101.84

    Now that you've determined the cost of your lights, which will be the bulk of your utility bill, you can do the same thing to calculate the cost of the inline fans and everything else.
     
    Cheers.
     
    - Dredd
     

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