The Garden Efficiency calculator....or gram per watt calculator

I finally did a search for the Garden Efficiency calculator and the first link took me right to it......so for those of you that want a way to measure and compare your production.......Here it is.

GARDEN EFFICIENCY RATING - Online Calculator

How much juice you burn to grow a gram..

Standard methods of reporting garden yields are imprecise and don't take the factor of time into account. This is a summary after discussion on a new standard formula for reporting yields and efficiency.

The GE Rating is based on the amount of kilowatt hours used to produce one gram. This factors in how long your strains flower and the resulting number makes it simple to compare 4000 watt gardens with 400 watt gardens. The calculations are easy, here is an example:

2000 watt flowering area
60 days of flowering
12 hours on light cycle
total yield: 49.5 ounces

1) Divide the total wattage of your lamps by 1000 to determine the kilowatts per hour:

2000 / 1000 = 2 kw/h

2) Multiply the previous result by the hours of the light cycle (usually 12):

2 x 12 = 24

3) Multiply the previous result by total days in flowering to determine how many kilowatt hours you used:

24 x 60 = 1440

4) Make sure your yield is in grams, so:

28.4 x 49.5 ounces = 1405.8 grams

5) Now simply divide grams by kilowatts:

1405.8 / 1440 =

0.97 grams per kilowatt hour, or a GE Rating of 0.97! Good job to the hypothetical grower, approaching a GE of 1 is the first plateau to be reached and is a sign of an experienced grower.

The secondary additions to the GE formula would be for the "Whole Garden GE Rating" which must include time spent in cloning and in veg. Figure it out the same way, with days spent under cloning lights, hours per day, and add those totals to the watt usage before dividing. This will give you a much lower rating than the standard Bloom GE Rating, but is more accurate for SCROG gardens, and anyone who is involved with extra vegetation time.

I prefer the whole garden method as I get the whole picture......but that's just me. I use this to tell how one crop compares to the next, based on something I changed.....so I know if it helped or not....it's a tool to help you know how you're progressing or losing ground....nothing more...
For example...you want to know if 75 degrees or 80 degrees does the best for you.........so you run a batch under each condition and compare the outcome.
You want to know if the $200 bulb was worth the money compared to a far cheaper bulb......same thing.
The possibilities are endless..
I hope you'll find it useful......

if this is correct then i get 2.25, is this correct or to good or what?

Can anyone think of a way to get a proper formula for a perpetual grow flowering room?

awkward said:

Can anyone think of a way to get a proper formula for a perpetual grow flowering room?

Click to expand...

Well assuming you're in motion you would have to take it out of a rolling period of time. I do mine by the rolling year (one year ago from today's date).

You simply take the second part of VidiotRayM's formula which gives you your KWH used per day. Multiply that by 365 (days in the year) and that will give you how many Kilowatt Hours used in that year. Next find your yearly harvest total in grams. Take your Harvest Total and divide that by Kilowatt Hours used in that year. That should give you the same GE rating as if you were to do it in specific time frame. Not only is the perpetual method better for growing but this method (I believe) is better because your GE rating can literally go up or down after every harvest which allows you to almost mathematically fine tune your grow. If you change something and it goes down you can always theoretically go back to your method of when it was higher.

Here's my grow on paper.

3200W in flower room / 1000 = 3.2KW per hour
3.2KW per hour X 12 hours per day = 38.4KWH per day
38.4KWH per day X 365 days = 14,016KWH per year

My average monthly harvest = 47.4oz = 1346.16g per month
12 months X 1346.16g = 16,154g per year

16,154g per year / 14,016KWH per year = 1.15g / KWH

As I said before this is a rolling number and is always changing. Hopefully better and better :]