looking for portable power for a concession stand. Any ideas except generators?

Answer 1

Have you considered using a 12V deep cycle battery with an inverter to supply 120VAC? If your car is parked nearby you could power from its battery, but be careful not to totally drain the battery.
There are small portable generators which make very little noise. If your concession stand is indoors this still wouldn't help much.

Answer 2

Depends what you plan to do with it; Light, cook, power appliances? Batteries (recharchable) , solar cells, and Gas are the most portable power sources.