For the first two summers I spent in my home in upstate New York, our lack of any sort of air-conditioning was tolerable. We had a solid ceiling fan setup and my other efforts to keep the house cool—drawing the blinds, making sure we had a good cross breeze going—were mostly successful. When it comes to A/C, my party line has always been that as long as I am cool enough to sleep at night, I can put up with one truly unbearably hot week each summer.

That rule started to fall apart once I, like so many of us, transitioned to a work from home lifestyle. The upside of no office air conditioner is that, as a woman, I don’t need to stash a blanket or robe at work lest I freeze to death. The downside is that, come summer, I sit in a warming house over the course of the day, feeling how I imagine a lobster must as it slowly boils in a pot of water.

Last summer, when that one unbearable week stretched to three long weeks with little reprieve, I knew something had to give. Our plan, eventually, is to install a heat pump—an efficient, environmentally friendly and increasingly popular alternative to central air for both heating and cooling your home. But in the meantime, I started researching the best temporary or semipermanent ways to keep the house cool. Surely, I thought, there’s been some improvement away from the ugly, dripping, clanking, dusty window units I had in my early 20s?

Well, yes and no. Ultimately, there is still no beating the window unit for cooling a home efficiently without central air. Portable A/Cs, though unavoidable for certain homes, are generally more expensive and more cumbersome than their window counterparts. Another option is a mini-split system, efficient and cheaper than central air if you’re looking to retrofit a house with but certainly more expensive and permanent than a window unit. So for renters, or for homeowners who eventually want to overhaul their system—but not quite yet—window units still reign supreme.

Are they pretty?

That said, there has been improvement in both efficiency and aesthetics from the window units of yore. The two air conditioners I called in to test—the July and the Windmill—are relatively recent direct-to-consumer models that, in addition to improving efficiency and user friendliness, are also more aesthetically minded than your typical big-box A/C. Both are minimalist in design, with rounded corners and clean lines, and come with magnetic plates in a variety of color options, which can be placed over the front panel to make the device look more integrated and streamlined with your walls and window frame. While not invisible, they’re a far cry from the eyesores I’m used to.

Both air conditioners were easy to install, with clear, concise instructions. The Windmill conservatively suggests leaving 45 minutes for set up, but we did it in 10 (flex). Because it tends to cool down enough at night here, I prioritized placing the A/Cs where we spent most of our day time, so the Windmill (made for a larger square footage) went in our main living area, and the July in our smaller sunroom, where my office is. While various factors limited us in which windows we could specifically install ours in, best practice for the most efficient A/C usage is to install the unit in a partially shaded area. Almost all window units are designed to be installed in double hung windows (aka those that open up and down), but July actually makes a unit for sliding windows that open horizontally.

Keeping the stickiness (and smoke) at bay

Beyond the heat, I had two other concerns I hoped window units might help mitigate. For one, the humidity: A/C systems help expel excess humidity from your home. The July, specifically, has a “dry” mode that works to reduce the humidity in the room without actually lowering the temp, which can in turn make you feel cooler. But keeping moisture out of the house doesn’t just benefit us on a comfort level, it can also prevent structural issues further down the line. High humidity can warp and swell wood and creates an optimal environment for mold and mildew growth. Yum!

Secondly, there are few places left in North America that haven’t been touched by migrating smoke during wildfire season. While investing in an air purifier or two would be wise, window units with proper filters can also help filter the air, though notably they will only filter out smoke that is already in your home.

What about my electric bill (and the planet)?

Of course, no matter what, using a window unit will consume more energy than going without. July acknowledges that directly on their site, with a page dedicated to sustainability that bluntly reads “Air-conditioning is bad.” Both Windmill and July run recycling programs for old A/C units and both use R32, a new refrigerant that supposedly has two-thirds less global warming impact than traditional forms. Both contribute to carbon offset programs (though these programs, it should be noted, are not without their own greenwashing controversies). Windmill runs an EcoRewards program, pledging cash to Windmill owners who decrease energy usage during periods of peak demand. And the July model has a “sleep” mode, which gradually raises the temperature over the course of the night.

What I found most helpful, however, was the data I was able to glean from the Windmill unit specifically. There has been extensive debate about whether it is most financially and environmentally efficient to let an air conditioner run continuously throughout the day, or to shut it on and off only when necessary. Ultimately, there are so many factors at play structural components and materials, insulation, ventilation—that what is most efficient for one home likely will not translate to another. The Windmill app, in addition to providing a remote thermostat and other programming perks, allows you to track the energy consumption of the A/Cs specifically: no more pouring obsessively over an electric bill trying to gauge approximately how much is coming from your unit. (Is that just me?)

What else can I do?

Other tips to making your air conditioner run most efficiently including replacing the filters frequently and calculating the appropriate BTU range for your square footage: sure, you can just run to Home Depot and pick out whatever is on sale, but if you buy a unit underpowered for the room it’s in, the machine will need to work harder to keep your home cooler, and you will likely lose money in the long run.

While I was disappointed to discover that in my years without A/C, there was no secret third thing waiting in the wings to keep me perfectly cool while remaining entirely invisible and having zero carbon footprint, both these units—quieter, sleeker, easier on the environment—helped take a bit of the sting out. For now, I’m more than happy to keep them chugging away—until I sell my first born for a heat pump, that is.

Top image courtesy of Windmill

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