Mathematically speaking, it would be described as a ratio problem with his 300watt LED in this case approx. equal to 1333 watt hps.
a ratio of 1:4.4444
Though in reality, I suspect the ratio is much lower perhaps 90watt = to 150hps or so...which would be 1:1.666
or in this case his 300watt...
That is roughly what Garden Knowm used. 8 is plenty for a smallish space. Larger spiral bulbs (more than 42 watts) are typically not as efficient. Divide the lumens/watt to be sure you are using the most efficient bulbs. You want at least 5-6K lumens of CFL per square foot.
If I were you, I'd save up all of $8 and buy a replacement power cord from your local home improvement store. And while you are at it, pick up a book on basic wiring. You do not want to wire CFL's in series.
This is particularly true with CMH. CMH has perhaps the most balanced spectrum for plants out of all the MH.
Also, LEDs lack far red which helps induce flowering. This is why it often takes longer to flower under LED.
There is some far red in the white LEDs, but it would take a lot of them...
I am all for this...however...
MJ is relatively easy to grow...and I suspect that if this does pass, all of the people who have these ideas of starting a large business off this will soon be disappointed. There are a lot of established people in agriculture who have the means and ability to...
It seems that eventually people begin to understand what is actually happening here. Think of Mercury Vapor lights...they might have a lot of lumens/watts...but horrible spectrum...and so the plant doesn't use that light efficiently. HPS spectrum is close enough to be useful; where it lacks in...
You can grow just fine in that. Obviously, the plant won't get as large, but you can definitely grow in it. There are plenty of people using 16oz containers doing mini SOG.
^^^ smppro has stated the truth. It has been said that CFL bud may actually be a bit MORE potent due to a more even balanced spectrum. CFL spectrum is close to combining HPS & MH. They just lack the intensity and therefore yield. If growing for personal stash, yields aren't that big of a deal...