[Al Skierkiewicz]

Jared,
You can use a common power point (a 20 amp breaker) as long as you don't have a ton of sensors on it. A big ball of wire attached to one lonely breaker is going to attract the attention of the inspectors. Grounds are the same but I recommend you run parallel wires from the sensors back to some common point. A custom circuit board is great for this. Even if there is nothing else on it, it can provide a convenient (and reliable) spot to terminate the power and grounds and it can be insulated inside a nice plastic box.