Don't want to rain on yer parade...couple drawbacks...
1) you get all the bad shit about being outdoors (bugs, yuck) without the benefit of sunlight
2) generators are expensive to just leave out in the middle of nowhere where a hunter is going to be like, hmm... that would work awesome at my camp!
3) someone finds it, your prints are all over the tinfoil. And you're out a lot of $ in lights and such.

If you're planning on growing outdoors, just do it regular IMO.