What is a good air conditioning option for camping?

Just some thoughts I had since I’ve camped in the heat a lot. I can’t do much since I backpack; it was only last year that I bought a cheap personal fan. If you can get one that will blow into one end of a flimsy tube (like the plastic sleeves they put newspapers into, taped end-to-end), put the fan at the top of the tent and blow the hot air outside. You could pin the exhaust end to the inside of a screen. Draw in outside air through the screen at the bottom. If you can stand the breeze, have a small fan blow directly on you. To shield your tent from the sun during the day, try one or more of those aluminized plastic emergency blankets.

Swamp coolers (evaporative) only work in very dry air and need a steady supply of both power and water. It can sit outside the tent and be ducted in with the flimsy tube idea. This cools the air stream, so the cooled air must flow through the tent–it can’t be bottled up. Check the power and water consumption and make sure it’ll work in your climate.

Ice coolers can cool and dehumidify. Some small models can sit inside the tent with hoses going to an ice chest sitting outside, but they use a huge amount of ice and need steady power (for a pump to bring cold fluid from the chest and a fan for the heat exchanger inside). I’ve heard that the cheap ones don’t work. If it works, you’ll need to provide for the condensate drip.

True air conditioners consume the most power but would work the best, assuming a plug-in campsite. Your best value would be the smallest unit that you can find at a thrift store such as Goodwill, or a closeout store such as Ollie’s. Set it outside and duct the air into the tent. Unless it’s an unusually large tent, it will probably get too cold to close up the tent with a second duct returning air to the unit (that one would have to be a collapsible spring wound one), so you could simply let it blow through. This will cool AND dehumidify.

Air conditioners go as small as 4,000 BTUs. For a small tent, you can get as low as 1,000 BTUs by looking for an "enclosure air conditioner" made to cool electronic equipment in cabinets. They’re smaller and consume less power, but they won’t be really cheap unless you can find a surplus/used one, and they’re still about 50 pounds.

The smaller you go, the more complicated it gets. To a point. You need a steady supply of compressed air to run a vortex tube, but these are also made for enclosure cooling. Put compressed air in one end, get two streams of air out–one hot and vented to the outside, the other up to incredibly cold. They shriek, but they’re also sold with mufflers. Don’t even think of getting one without.

If your tent is small enough, try circulating air through one of those cube refrigerators using ducts and a small fan. These are in your price range, and you can sometimes pick those refrigerators up for free if you cruise around during a township’s large item pick up day. Fasten some sort of finned heat exchanger to the icebox. If you’re ambitious, cut most of the case off from around the guts, being careful not to disturb the tubes. Add the finned heat exchanger. Pop rivet what you need of the case back on, adding a fan. And a second fan on the coils in back. This sounds like a worthy project. It will drip. It could also ice up. So? Space the heat exchanger fins farther apart. What do you want for free?