Staying Cool

Summer in eastern North Carolina

Not only is it unpleasant to be hot, people and pets can die if they get too hot, so we have here some ways to stay cool.

Replace Or Clean Filters

Replacing or cleaning the filter of your air conditioner will help it blow more air, increasing the rate at which it replaces warm air with cool air.

Fans

Fans make us feel cooler by moving air over our skin, which causes evaporative cooling of our skin. Blowing a fan where no one can enjoy it is unlikely to be helpful. It will only keep the hot air from collecting at the top of the room. It will in fact generate an amount of heat equivalent to its power usage. A 60-watt fan circulating air within a room will continually add 60 watts of heat to the room.

(This is according to the laws of physics, thermodynamics in particular. All of the power from the fan gets converted to heat eventually. A tiny amount may escape the room as vibration and EM radiation before it is converted to heat, but even the power from the fan that actually moves the air is converted to heat in the room as the air molecules keep bouncing into each other.)

Clean Fan Blades

A fan will typically only blow well for a few months. The problem is that dust accumulates on the blades of the fan. If you clean the blades and the front grill, the typical old fan will blow like new. Just unplug the fan, unscrew or unclamp the front grill, and wipe of the blades with a damp paper towel, being careful not to get water in the motor, switch, or on the wiring. Keep cleaning until no more dust is coming off. Clean the removed front grill with a water hose or scrub it with a brush like you would clean tires with.

Simulate Rain

You could spray your roof and/or sun-facing walls with a water hose. The cool water will reduce the temperature of the surface, and evaporative cooling will continue to cool it until the water evaporates.

Water can absorb a lot of heat, so it doesn't take much water to achieve significant cooling. I'd only spray for a few seconds every thirty minutes or hour during the hottest midday hours, but I wouldn't even do that during a water shortage, a drought, or when the water table is unusually low.

Bear in mind that your roof was designed to generally only have little drops of water falling on it from above. Spraying a high pressure stream of water on your roof from a near-horizontal angle might damage something or cause a leak. Try to spray so that only little droplets fall on the roof from above, as vertically as possible, like a light rain.

Ductwork

In many old homes, the ductwork is full of debris or even falling apart, making the central air conditioning unit extremely inefficient. Make sure your ducts are clean and still attached to the vents and hope they aren't leaking, or use window AC units.

Window Units

I like window-mounted air conditioners because they avoid the problems with ducts and allow you to cool one room instead of the whole house. You just need to try to seal the room as best you can because the cool air leaks out and hot air leaks in through small cracks around doors and windows.

Reflect Sunlight

Direct sunlight shining in windows can be a major source of heat. Light-colored blinds and curtains can reflect much of the sunlight back out the window. Mylar would probably do better. I've also considered Christmas-style window frosting. A better solution would be to cut white hardboard panels to fit your windows. It would be even better to have a layer of insulation held between the glass and the hardboard. There are all kinds of ways to reflect sunlight back out windows and add insulative material - just pick one.

Trees

You want to cut down trees when they're dropping limbs, leaves, and pollen all over everything. You live in constant fear of being crushed by a limb in your yard or being smooshed by a falling tree while lying in bed. But they do provide much-needed shade and save money on the electric bill.

Exploit Nature

During a brief rainshower or storm is the time to turn down the thermostat on the AC. Rain and wind help the outside heat exchanger work better, so cooling requires less power than when the outside part is 150 degrees in direct sunlight.

If it's cool enough outside, an open window can provide free cooling. A cool breeze often surrounds summer storms, and you can open the windows to exploit it if you see it coming. Even if the storm misses you, you still get the cool gusts. You can sometimes spot a cool gust on the weather radar as a thin little shockwave coming off of storms.

A fan in a window can be even better than waiting for the breeze to move the air. You really need two open windows, one for air to come in and another for air to go out. You could rely on cracks in the structure for either intake or exhaust of air. If your window fan blows inward, there's a greater chance of sucking rain into the fan or the room or both. If it blows outward, you could end up with negative air pressure in your home, which I've heard is bad, but I'm not sure why. However, I do turn off the window fan during heavy rain to avoid sucking rainwater into cracks.

Off-peak Hours

I'm not sure about Rocky Mount, but some places that use smart meters give lower prices for electricity at off-peak hours, so there's a possibility that you might get more cooling for your buck at different times.

Light-Colored Roof

It seems counterproductive that most shingles are black. Black is the hottest color in direct sunlight, reflecting the least sunlight and converting the most into heat. If your roof is in the shade most of midday, the color doesn't matter too much, but if you're in direct sunlight during middle of the day, consider a light-colored roof.

Turn Off Heat-producing Electronics

If you're struggling to stay cool or just want to reduce your electric bill, turn off any electronics or appliances that you don't need. Don't leave the TV on when you're not watching.

LED Lights

LED lights produce much less heat than incandescent bulbs, so while incandescent bulbs waste hardly any power indoors when it's cold out because you need the heat anyway, they do waste power when it's hot out. If you have 240 watts of cooling power coming into a room but you turn on two incandescent lights that each produce 60 watts of heat, you've diminished your cooling power by half.

Appliances

If you're on an oxygen machine, consider placing it in another room, using tubing to get the oxygen to you, but bear in mind that you also need to keep the machine from getting too hot.

Pets

Make sure pets have cool, shady places to rest and multiple water dishes in case one gets turned over. Water dishes can get very hot in the Sun, so try to keep them in shady spots. Shadows move as the Sun moves across the sky, so make sure there's shade at different times of day, especially midday and afternoon.

Conclusion

In conclusion, it's hot out there, so try to stay cool. Use your ol' noggin.