i got 30 girls in 5gal pots im looking for atleast 1/2 pound per plant vegging for them to be atleast 2-3ft tall hopefully topping 3-4 times please let me know what i need to reach this goal
If you want to grow a 15 pound crop then what you need more than anything is a LOT more experience than you probably have.
When you're ready to do what amounts to a small/mid sized commercial grow you'll know how much lighting you'll need, how to maintain your plants, etc. Starting off with that size of a grow with negligible experience is a recipe for disaster.
The fact that you already have 30 plants going, but don't know what sort of setup you want to put them in, means, at the very least, that you didn't quite think things all the way through here!
Not to be too mean about this, but the FIRST thing you do is setup and equip your grow room correctly. There is a lot more to it than just plugging in a whole bunch of lights. There are electrical safety issues, cooling, ventilation, potentially light movers, humidity, odor control, etc. These things aren't "rocket science", but they're absolutely critical to a successful grow. You do these things BEFORE you start sticking plants in 5 gallon buckets.
But to answer your question, as a first approximation, figure if you're a competent experienced grower, you can pull maybe 0.75 grams/watt with the right strains. So your 15lb target equals about 6800 grams, meaning you'd need roughly 9000 Watts to get there. If you're a top level experienced pro grower, AND you use the right strains, once you get everything perfectly dialed in, you might be able to do it with only 7000 watts of lighting. Note that these figures exclude other necessary energy consumption from cooling, fans, timers, security, water pumps, etc.
Now though it "could" be done with that little juice, it this actually applied to you, you wouldn't be asking the question.
As a novice, you'd be lucky to pull 15 lbs with 13000 watts of lighting.
My polite suggestion to you is to start smaller. Once you have 3-4 crops worth of experience growing only a few plants and strains at a time, THEN you might be ready to move to gigantic kilowatt commercial sized grows, but not before.