I love a good debate SME
I wont tell you that you are wrong, just that we may have different opinions. Nothing wrong with that. I think we can both agree that there are so many factors to consider when choosing any style of lighting. It greatly varies from set up to set up. Which we both agree upon.
Had some errands to do until now, so due to time will have to keep this short and sweet.
With ballasts I am not sure I would agree that they last for 15 years, not even sure when they reccomend to change them in number of years our amount of hours used. I do however know from another growers experience over the past three years they have had to replace their ballasts once each (a 400W and 1000W Ballast). The 1000W was about a year and a half ago and the 400W was in the past 6 months. You may know alot more about this and if it is a problem or not, but their 1000W ballast is currently "leaking" this brownish liquid from where the power supply is connected.
I know with LED's there can be similar types of issues with diodes burning out and needing repair or replacement, and over time (longer use with LEDs IE: 5-10 years) I would imagine even the best built system will still have some minor issues.
The coverage area that is recommended vrs what you can actually get away with will vary by which company you choose and how the LED light is manufactured. The Lens quality and angle play a huge factor in this, with regards to 60, 90, and 120 degree angles.
I personally would not imagine that the average or common grower is usually growing trees much larger then 5 feet tall, and there are many videos showing commercial growers with huge facilities and an abundance of space who grow plants that tall and producing comparative if not better yields to MH and HPS.
When it comes to the intensity of the light I will quote from the supplier since I am not an expert by any means, and it is easier to understand comming from the horses mouth.
"The inverse-square law states that the intensity of light radiating from a point source such as LED, is inversely proportional to the square of the distance from the source. This means that an area (of the same size) twice as far away from a light source at full intensity, receives only one-quarter of the energy as shown in the image to the right. As distance continues to increase from the source, light intensity subsequently decreases.
The most popular methods of measuring light intensity are expressed in units of lumens or PAR. Lumens express how intense a light source is to the human eye, while PAR expresses how intense the same light is to plants. HID manufacturers have been confusing people for decades by rating their products in lumens, when this has nothing to do with photosynthesis or quantum efficiency. So while a 1000W HPS may emit 145,000 lumens to the human eye, the PAR (photosynthetic) value they emit at 12" is roughly 2000 micromoles, which is equal to the sun on Earth. Therefore, when comparing HID to LED, the only reading that matters is micromoles.
Light Intensity is determined by 2 factors: the total light output from a source, and how it is dispersed over an area. Our GS600 grow light produces over 2000 micromoles at 12" from the glass, rivaling the output of a 1000W HPS!"
I use this quote to illustrate that it is more then possible (once again depending on your setup up and all the other factors involved) to replace your 1 1000W HPS light setup with 1 600W LED light. If you are able to achieve this for your set up that is where the energy savings come into play. Using your own breakdown the HPS setup is using over 1100 W compared to the LED (gs 600 and pro bloom) which is only using 550W. Since the heatsinks are already included in the wattage for the usage of the LED light there is no additional added cooling cost energywise to run this set up. The only need of an ehaust fan is to help control odor and you will need osilating fans (if you wish) regardless of the lights.
Using my personal setup my fellow grower's current set up with MH and HPS (400W and 1000W) is able to grow and bloom upto 15 trees in soil. The 400W is on 24 hours a day and the 1000W is on 12 on 12 off. Correct me if I am wrong but I would assume that is 400W and 1000W an hour in usage? If that assumption is correct the 400W would equal 9600W a day and the 1000W would be 12,000W for a grand total of 21,600W.
Compared to my setup with double the plants and an extra LED light, lets see how that will compare...
2 300W with an actual out put of 240W on for 24 hours a day is 11520W and the 3 600W LED's will be on for a 12/12 cycle for an actual draw of 19800W. My grand total is 31,320W, if they doubled their setup to properly compare to mine then they would have a total of 43,200W a day usage. Even with an extra 600W LED light I am still 11,880W lower on a daily basis. That is a huge savings over time. I didn't even add on to that the added cost of running the air cooled fan at 100W an hour on the HPS 1000W bulb. That would make it over 13,080W less usage if you have it on for only 12 hours at a time.
I would imagine that my setup is rather large for the "average" grower I would guess that the majority of hobby growers have less then 10 plants and limited space.
If your aim is to convince growers to not switch to LED and stick with HID such as MH and HPS, either for the comfort factor or because it effects your business (?? not sure since you mentioned that you have clients), lets face it, HID is a easy proven way to grow and you know exactly the output you should gain from using HID as your lighting source. Now I am currious if you are just a shop owner or if you maybe somehow involved in the making of HID lighting??
Either way you seem to be very knowldgable about what your speaking about, extreemly helpful with many good ideas and suggestions, and I am happy to have crossed your path and spoken with me
The one thing I would be pointing out to people considering switching from HID to LED is the number of phoney claims out there by LED makers. Many are fraud, such as the post I made with regards to hydrogrowled, just relaying the hard work and information done by members of other forums. Even some widely used and popular companies that sell LED lights use some very misleading misinformation. I spoke directly with a few companies who claimed that their products are more expensive due to the fact that they use only Cree diodes, when based off their own spec's anyone can research and see that cree does not make the color spec or style of diodes they say that is in their product.
"Another trick many companies like to use is naming their LED Grow Lights off the "LED Wattage". For example one company makes a light called the "357 Magnum" and even puts the power consumption as 357W, however the light uses only 119 x 3W-3Chip LED's, or it has 357 chips. The actual power consumption of the unit however, is only 166W. Companies like this use mis-directed marketing and false labeling to convince the customer they're getting more than they really are!"
Above is another quote that can explain it better then I can.
If you are using a 3W-3 chip LED and planning to grow a larger number of soiled trees (3-5 feet tall) you will find yourself in some serious trouble if you try and achieve this with only 1 or 2 or even 3 of the above mentioned lights.
This whole debate (maybe I am showing my age) reminds me of the whole beta vrs VHS, only HPS and MH are the beta and VHS and LED would be more like DVD. Sure the technology is still comming along and has leaps and bounds to go to become even better then it already is, however it takes people willing to take a calculated risk with alot of due dilligance to purchase the lights to keep the good LED companies going with enough dollars in thier pocket to invest in further R & D.
The one thing we have yet to speak of about one major advantage that LED has over HID lighting is (what made me decide to purchase my lights from this company) the addition of "green" lighting being used along with the other 3 regions of PAR. When I first heard of this I was thinking the exact same thing as you probally are right now, why would you use "green" lighting it is no added value or benefit??
However after I did a little research on my own (thank you google) I found some information (most of which made my head hurt) and after a few weeks of reading I found out there is some method to their madness. NASA has studies which you can find on the web and read up upon that show/prove that you can drastically alter the flowering times and yields of plants when you properly balance all the areas of red and blue light ( 439 NM 469 NM 642 NM and 670 NM), that they can absorb more red and blue light when in the presence of green light.
When you are using HID (MH and HPS) compared to all LED makers (except grow stealth led) HID has this advantage over LED as HID is offering the green in the full spectrum compared to tri and quad spec LED. Not to be confused with stealth grow, grow stealth was the only LED company out there to focus on the actual science of growing and making use of this occurrence.
I already mentioned about the lower amount of nuets needed during LED grows compared to HID due to the fact the the temp it operates at is much lower for LED and therefore has less evaporation due to the lighting source. That is what I kept hearing over and over and over again from growers or people who are in regular contact with growers who had already switched to LED lighting. Nuet burn and root rot was a major problem for many growers since they used the exact same feeding schedual and routine, yet the only thing that changed was the Lighting souce.
Anyway I will await your reply I have go on for awhile.