Scarfinger68
New Member
I am using some harvest numbers from Doc Bud's journal Doc Bud Tries The G8 450 LED From Dorm Grow!
As a small home grower I just upgraded from CFL to HPS. But I have also been looking at the LED lights and prices. Also I have been looking through some LED journals and I see somewhat of a trend. It seems like some people are really exited about their new LED and they portray an excitement that would make you think that LED is kicking HPS's tail.
I am not trying to put any blame to anyone and especially not to Doc Bud. He is a quality grower and I respect him. I am just to lazy to get numbers from everyone who has done a side by side... which seems to be hard to find.
I am going to do some calculations and then make some conclusion of my own. I just hope that this post encourages other to do their own research and make educated choices.
Numbers generated from Doc Bud's journal:
LED: (352w total)
G8 450 power draw 280w + G8 Flowering BOOST power draw 72w = 352w
1 plant in 3 gallon pot
Harvest (28.3 x3)+3= 87.9 grams / 352w = 0.25 g/w
HPS (1000w total)
2 plants each in 7 gallon pots
Harvest “just under 6 oz. each plant” ((28.3 x6)x2)-4 = 335.6 grams/ 1000w = 0.34 g/w
*the (-4) is an estimate for the “just under 6 oz. using -2 grams as “just under” for each plant
So to me I don’t exactly see how the LED "uses far less energy"
That statement is only true if you looked at the total watts used of 352w compared to 1000w. But the HPS had better efficiency at 0.34g/w compared to the LED at 0.25g/w.
If you take into consideration the watts used by fans and air conditioning units then the HPS may come close to the 0.25g/w range which would take a total of 1342.4 watts used by the HPS system, (HPS+fans+air conditioning). So it would take an additional 342.4 watts by the HPS system to perform g/w as low as the LED.
Things to consider.
1. If the LED was grown in a 7 gallon pot it would of done better increasing the g/w number
2. Maybe a 600w HPS light could have been used decreasing watts used and increased the g/w number
3. in the end this is only anecdotal evidence and more grow experiments are needed.
Start up cost:
HPS:
$100 reflector + $100 balast + $60 bulb + $100 fan = $360 + replacing bulbs ever 3 grows or so.
LED:
Compared to $600 LED + $100 fan = $700 lasting 50,000 hours.
I am looking at this on a small scale home grower perspective:
In conclusion I am not saying LED isn’t worth your money or that HPS is a waste of money. To me it comes down to money and what you can afford to start with, and also your personal preference.
It may be like buying a new car outright (LED) or leasing a new car (HPS) because you can’t afford the down payment to buy the new car (LED).
The one thing I don’t generally agree with is the excitement that growers portray when using LED lights. It sounds like LED is blowing away HPS but by breaking down the numbers (which is kind of hard to do without side by side clone grows) I would say LED is almost as good as HPS or maybe = to HSP at best.
I would like to say in closing that one day I will probably buy an LED.
As a small home grower I just upgraded from CFL to HPS. But I have also been looking at the LED lights and prices. Also I have been looking through some LED journals and I see somewhat of a trend. It seems like some people are really exited about their new LED and they portray an excitement that would make you think that LED is kicking HPS's tail.
I am not trying to put any blame to anyone and especially not to Doc Bud. He is a quality grower and I respect him. I am just to lazy to get numbers from everyone who has done a side by side... which seems to be hard to find.
I am going to do some calculations and then make some conclusion of my own. I just hope that this post encourages other to do their own research and make educated choices.
Numbers generated from Doc Bud's journal:
LED: (352w total)
G8 450 power draw 280w + G8 Flowering BOOST power draw 72w = 352w
1 plant in 3 gallon pot
Harvest (28.3 x3)+3= 87.9 grams / 352w = 0.25 g/w
HPS (1000w total)
2 plants each in 7 gallon pots
Harvest “just under 6 oz. each plant” ((28.3 x6)x2)-4 = 335.6 grams/ 1000w = 0.34 g/w
*the (-4) is an estimate for the “just under 6 oz. using -2 grams as “just under” for each plant
So to me I don’t exactly see how the LED "uses far less energy"
That statement is only true if you looked at the total watts used of 352w compared to 1000w. But the HPS had better efficiency at 0.34g/w compared to the LED at 0.25g/w.
If you take into consideration the watts used by fans and air conditioning units then the HPS may come close to the 0.25g/w range which would take a total of 1342.4 watts used by the HPS system, (HPS+fans+air conditioning). So it would take an additional 342.4 watts by the HPS system to perform g/w as low as the LED.
Things to consider.
1. If the LED was grown in a 7 gallon pot it would of done better increasing the g/w number
2. Maybe a 600w HPS light could have been used decreasing watts used and increased the g/w number
3. in the end this is only anecdotal evidence and more grow experiments are needed.
Start up cost:
HPS:
$100 reflector + $100 balast + $60 bulb + $100 fan = $360 + replacing bulbs ever 3 grows or so.
LED:
Compared to $600 LED + $100 fan = $700 lasting 50,000 hours.
I am looking at this on a small scale home grower perspective:
In conclusion I am not saying LED isn’t worth your money or that HPS is a waste of money. To me it comes down to money and what you can afford to start with, and also your personal preference.
It may be like buying a new car outright (LED) or leasing a new car (HPS) because you can’t afford the down payment to buy the new car (LED).
The one thing I don’t generally agree with is the excitement that growers portray when using LED lights. It sounds like LED is blowing away HPS but by breaking down the numbers (which is kind of hard to do without side by side clone grows) I would say LED is almost as good as HPS or maybe = to HSP at best.
I would like to say in closing that one day I will probably buy an LED.
New knowledge 
