I was wondering if there is any rule that says how high the lights must be? In my opinion these portable lights don't really light the field up enough, and it favors the running team more. Is it up to the refs to determine if there isn't enough lights or is there a specific rule?

No, Brother Rober the First, I don't believe that there is a specific rule that governs lights. Now, you could have a district rule that prohibits temporary lights.

But unless you (1) rent an existing field with lights or (2) own an existing field with lights (which can be expensive), temporary lights are about your only choice.

And if you have to rent them at "rack rate," it can cost you as much as $800 or so a night plus diesel fuel to refill the tanks.

My only complaint is about folks who think they can use four banks of portable lights ... you really need six, or you will have some significant dead spots (usually in the endzone).

The only playing rule is that the Referee may elect to shorten the quarters if he thinks the game may be interupted by darkness. Now, me personally, I would never ever do that on my own. I would make sure that both coaches were in favor of using shorter quarters.