For years, growers have known that spectrum degradation happens even though the human eye can’t see it happening. What they can see is the diminishing yields the longer they leave lights running.
With the rapid expansion in the commercial sector, multiplying this loss by hundreds and even thousands can severely dampen return on investment.
The graph below depicts spectral degradation of an EYE HORTILUX Super HPS lamp over the course of 12 months (running for 12 hours a day).
As you can see, under standard conditions. HPS lamps will degrade 20-22% over that first year.
You can see the loss of spectrum in the graph, but the real loss comes down to profit.
In the above graphic, we took a look at what this spectral degradation means to your profit in the end. Let’s make a few assumptions. In this case we aimed low on both yield and market pricing.
- Average yield = 1.5 lb/1000W light (680g)
- Price per lb = $1500 (roughly $2.20/g)
- Decrease in yield = 10%
Now let’s calculate this to find lost profit using the following equation:
total yield x % decrease in yield x price per pound = total lost profit
1.5 lb. x 10% = 68g x $2.20 = $225 lost profit
So, now saving money by not changing out lamps just cost you money. And that’s just for one light!
This is why changing out your grow lights regularly based on manufacturing recommendations is so important. In this case, every 12 months for the Super HPS (with a 12 hour burn time per day).
Click here for a downloadable of this example.