I think it depends on where she lives and how hot it gets, wintergirl. If she's in the high country, it may not hit the temperatures we hit. She may also have a house with thick adobe walls. If it is humid outside, the swamp cooler gets turned off, the windows get closed, and the AC goes on. It stays that way until the rainy season is over and the humidity is down again.
In the greenhouse, AC would keep things cool, but since part of what AC does is remove moisture from the air, it wouldn't help the orchids much.

I remember having to switch from a swamp cooler to AC when the summer monsoons hit Tucson. C'est la vie!

Cattleyas can do well with less sun during the summer, mainly because many of them come from places where the summer rains cause local trees to put out more leaves, thus reducing light to the orchids below. Just be sure to crank your fans on high so there is a lot of air movement. My Catts do just fine with the 105 temps common to the Central Texas summer. Do you best to get humidity up as well.

Here at the Lowes in NM (Texas Pan Handle area) they have giant fans and something that sprays water in front of them. Refreshing!

Strangely in the hot southwest, you get quite a difference in sunlight in shadow and night and day. The heat diffuses quickly when no damp grass is holding onto it. Potential suggestion? Plant grass in the greenhouse?

If I continue living out here, I will be putting an aquaponics setup in the greenhouse. Cat fish, a few heads of lettuce and orchids. Should keep things quite steamy.

She lives in Albuquerque, New Mexico. It gets very hot there. She does have an adobe home.

I live in Clovis. Albuquerque is much cooler. I grew up in Albq.

Albuquerque is considered a cold desert and according to weatherspark, it rarely gets above 98. Tucson's hottest temperature was 117. Albuquerque is at 5253 feet, while Tucson is at 2643. Albuquerque is also considerably farther north than we are. All those things factor in to how hot and how dry it is, and how well that swamp cooler is liable to work.

Sometimes, Ohio doesn't seem so bad. :)

LOL! Yes, but other than the heat, this is a pretty benign place. Not buggy...too dry for mosquitoes. You can almost always eat outside and not worry about flies. The critters we have are big enough so you can see them coming, and often slow enough to hit with a tennis racket. No blizzards. No tornadoes. Flash floods don't last long. And the time that isn't summer is delightful! Winter attire means shoes with toes, as opposed to flip flops, and maybe long pants and a long sleeved tee shirt. Pop on a sweatshirt if it gets REALLY cold...like 30! ;-)

Hmm, it is as if you know this place. :|

I am originally from Chicago, Leafmite. We moved here in the late 80s when the walls INSIDE our house had ice on them! I also have a not-so-pleasant memory of the fruit turnover that I was enjoying until I saw half an earwig in the next bite!!!
I'm much better able to handle the heat than the cold. I get up before dawn to do my bike ride when it is in the 60s, and wait until days like today to swim so that the water is warm enough.
For humans, it is pretty sweet. Live in a cooled house, drive your air conditioned car to an air conditioned mall or work. If you pick your activities for early or late in the summer, you're golden.
My orchids, however, are not having a good time. I don't dare put them out until the rains come, because 8% humidity is just no fun for them.