Tuesday, November 28, 2023


Desktop air conditioner a waste of money

By Mike Sokol
Dear Readers,
As part of my continuing effort to help you avoid electrical gadget schemes, here’s an interesting one that was emailed to me a few days ago about a magic air conditioner that runs from USB power (less than 5 watts) and supposedly cools your entire office area.

According to all the marketing hype, this gadget will help save the planet because you’ll no longer have to spend thousands of dollars on an “evil” conventional air conditioner, and won’t have to pay the utility company hundreds of dollars a month in electric bills.

Scam Alert

So, could this be true? Do these German scientists know more than all the other air conditioning designers and manufacturers in the world? Or is this an elaborate plot by the air conditioner cartel to keep you buying expensive air conditioners for your home and RV, when all you need is this little cube sitting on your desk plugged into your laptop USB port?

Save your money

Yes, this is just one more effort to separate you from your hard-earned money, so don’t fall for it. Considering that something like 10% of the entire world’s electrical power is used for climate control, don’t you think if there was some cheap and simple way to reduce that number by some 99% that the entire industry would be grabbing onto it?

Just like gasoline magnets that are supposed to improve your MPG by 50% and electricity “cleaners” that claim to reduce your power company bills by 95%, this is simply bogus advertising – so don’t fall for it.

If wishes were horses…

Yes, my favorite quote about technology is: “If wishes were horses, beggars would ride.” Science is just science, and no matter how badly I might wish for something, the laws of physics are unbreakable. The greatest minds in the world have been working on air conditioner technology for more than 100 years. And, yes, even Albert Einstein held a patent on a refrigeration unit with no moving parts. See, he wasn’t just a one-trick pony. AE studied all sorts of things.

Yes, you may be able to find a way to negotiate around the laws of physics at times (which is why heat pumps are more efficient than resistance heating), but there’s no way to ignore thermodynamics.

So does this magic air conditioner work at all?

Well, sorta kind of. It’s essentially a fan in a box that you add water to that creates a mist. And if you know your science, to evaporate water you need to add energy in the form of heat. And that creates a cooling effect exactly like splashing water on your face and fanning it, or even using your own body’s air conditioning system: sweat glands and a breeze.

Yup, this so-called magic air conditioner sprays you with a mist of water in a breeze. So if the room isn’t too hot and has low humidity, you might get a little local cooling effect. But no more so than a water bottle fan, or even flapping your arms to dry your own sweat.

Enter the swamp cooler

For those of you who live in a desert environment, you can actually get a large version of this called a swamp cooler. Its real name is an Evaporative Cooler, which is used in hot and dry warehouses all the time. As you can see, this is a lot larger and uses much more power than the imaginary air conditioner powered by a USB port.

But Evaporative Coolers only work in low humidity and will try to turn your room into a tropical rain forest. Again, they might be useful under some circumstances, but they’re largely impractical for most of us most of the time. And an evaporative cooler (aka swamp cooler) certainly won’t replace a rooftop RV air conditioner where we want to REMOVE humidity, not ADD humidity.

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Tom (@guest_121206)
2 years ago

My DW family used a car window mounted swamp cooler on trips from CA to TX each summer.

Steve (@guest_121028)
2 years ago

Our only home air conditioner for the past 45 years has been a rooftop “swamp cooler.” We have never been uncomfortable in even 100+ degree July weather. But we also live in the Denver area, which has an annual average precipitation of 14″ and an average humidity of 25%. So the swamp cooler not only cools us, but it adds a little indoor humidity, which makes summer sleeping even more comfortable.

I have even thought about installing a TurboKool evaporative unit on our fifth wheel, since our only summer camping is in the mountains of Colorado and New Mexico. Our RV travel to other parts of North America is only in fall-winter-spring, when an AC unit is seldom needed.

dave d (@guest_121007)
2 years ago

It’s a humidifier, not an air conditioner. That said, here in Utah, I have to use a whole-house humidfier in the winter. It the summer, we cool the entire house with a roof-mounted swamp cooler. I love it. Except for about two weeks every August when a monsoon pattern sets up with hot, humid air flowing up from the Gulf of Mexico. It can only keep the temperature down to 74 instead of my preferred 68. But we just stay in rooms with ceiling fans going, and it works out. 

William Hall (@guest_120941)
2 years ago

We cooled our house in the hot, dry, Kansas summers with a swamp cooler. There was many a hot night when I would drag my blanket into the living room and sleep under the swamp cooler.

Mike Sokol (@guest_121003)
2 years ago
Reply to  William Hall

Yes, a swamp cooler can work very well in a hot and dry environment, but I’m guessing yours was a little bigger than this USB powered desktop toy.

Tom (@guest_120915)
2 years ago

“A fool and his money are soon parted.” “A sucker is born every minute.” And many other quotations cover this subject.

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