One of Phoenix's biggest resources is not being exploited, and that is sunlight. There are a few solar plants around Arizona, but Phoenix itself could be one large solar plant.

There are many unused spaces where solar panels can be placed. One is over side walks, where many people have already expressed a need for shade. Dual purpose.
Put Solar panels over some streets, over all alleys.
You can also enact an ordinance which would eventually force all structures or parking lots to have solar panels.

Could you imagine parking in shade all the time? How great would that be?
Hopefully we can get to a point where no one in the city has to pay for electricity!