Indoor Yield-O-Rama

Basic Expression Examples

About the Examples
The garden with the gray highlight is the control, it's used as a point of reference in each set of example comparisons. This is also the sample data used in the calculator when you click the Insert Sample Data button. Raw data used for the examples was purposely chosen to make the desired points. It is realistic given the vast differences in production that can be expected between gardens and gardeners in the real world. Lamps used in the examples are all HPS lamps.

Basic Expression Examples
Garden & Crop Production Yield Expressions
Total Weight
dried manicured
square feet
(sq ft)
Illumination Physical
total lumens
(g/sq ft)
284 8 49200 400 35.5 5.8 0.71 123
284 10 49200 400 28.4 5.8 0.71 123
284 12 49200 400 23.7 5.8 0.71 123
284 14 49200 400 20.3 5.8 0.71 123

When we compare yields for the four gardens above they differ only in the canopy space they use. Total weight and illumination are identical. Of the yield expressions shown, only Space hints that the first garden was operated more efficiently than the rest. The other expressions aren't showing that the first garden is actually yielding the same from fewer resources, their ratings don't give due credit for using less space more productively.

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(2) These use identical space but have different illumination and total weight.

Space Light Energy LPW
162 10 28000 250 16.2 5.8 0.65 112
284 10 49200 400 28.4 5.8 0.71 123
502 10 87000 600 50.2 5.8 0.84 145
780 10 135000 1000 78.0 5.8 0.78 135

The total weight for each garden was purposely chosen to produce the same Light rating as the control garden. With the Light ratings identical it becomes easy to see how the Energy expression is biased towards lamps with a higher LPW rating. Notice how the 0.84 Energy rating (the highest) comes from the lamp with the highest LPW, and how the order of the Energy figures follows the order of the LPW figures not the order of the Space or Light expressions. And though the order comes close to matching the Space figures, we know by the absence of space in the Energy g/w formula that it's the total weight figures typical of larger lamps driving the Energy values, not the scaled weight found in the Space expressions.

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(3) Same as above, but with different spaces.

Space Light Energy LPW
162 5.70 28000 250 28.4 5.8 0.65 112
284 10.00 49200 400 28.4 5.8 0.71 123
502 17.65 87000 600 28.4 5.8 0.84 145
780 27.50 135000 1000 28.4 5.8 0.78 135

The canopy space for each garden was purposely chosen to produce the same Space expression ratings as the control garden. Notice how the identical Light & Space ratings suggest that each garden's physical resources, regardless of their scale, were operated with the same degree of efficiency, but the order of the Energy expressions are still commensurate with the lamp's LPW. Using Energy as a measure of productivity could lead one to believe that certain growers run their gardens more efficiently than others, when in fact it shows which lamps run more efficiently than others, and that the higher grams associated with larger lamps are more a matter of scale than skill.

And when you think about it, why shouldn't the fourth garden have more total yield? And why should having almost 5 times more space and light as the first make it more efficient? It's not what you got that counts for efficiency, but how well you use it! The first garden, though on a smaller scale, was operated just as efficiently as the others given the unique physical resources each had to work with. Energy resources, on the other hand, speaks more for the efficiency ratings of lamps than it does for their efficient use.


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