I wondered the same thing... but is there a reason to NOT go solar?
Playa dust. Dust Storms and wind covering the panels lowering efficiency. That's one more item to worry about. Given that the temp spike is in the noon area, we probably wont NEED it at all times. The pump/fan combo draws little power, a 100+ aH deep cycle should be good for the 8 days.
I will be powering it with a battery of some kind. We have a solar panel just need to standardize on power sources for the camp. Open to battery suggestions! Right now I just have a DC wall outlet I'm using. I used a combination of Figjams guide and this one: http://graywolfsurvival.com/2365/how-to-make-a-5-gallon-bucket-air-conditioner/. He recommended against solar, and I think even Figjam wasn't only solar, he had battery backup.