A few years ago, some fool in RV sales management came up with the idea that putting jet black plastic covers on RV rooftop air conditioners would look really cool. It would boost sales. And, it did. It appealed to our basic vanity, that something must not just be functional, but sporty and stylish, too.
That guy ought to be flogged for the environmental damage from the extra wasted energy he personally caused. Moreover, he must have been asleep all through high school science class. He certainly never took applied physics.
If he had, he'd have known about the "black body theory". A black body is an idealized physical body that absorbs ALL incident electromagnetic radiation, regardless of frequency or angle of incidence. The name "black body" is given because it absorbs all colors of light. Especially heat.
In contrast, a white body is one with a "rough surface that reflects all incident rays completely and uniformly in all directions." [ Source Wikipedia]
In English, that black plastic surround on your Dometic or Coleman rooftop AC or heat pump is a "black body" and is actually absorbing heat, drawing it in.
Under that black plastic shroud, at one end, theres a condensing coil that has a fan blowing across it, whose sole job is to cool down hot refrigerant gases. Beneath the cover, below the roof line, separated only by thin sheet metal box, is the evaporator or cooling coil, which draws warm air out of the space using cooled refrigerant. A cycle that repeats over and over. Basic thermal transfer.
Wanna make this process harder and horribly inefficient? Change the plastic shrouds from bright polar white to jet flat black. Nothing sucks in more heat than that color (or lack of a color as Sheldon might argue.) It is a terrible concept. How it got past the engineering department baffles me.
But, black shrouds caught on faster than a new Nike design, and no one complained. Except me. I took HVAC engineering and physics. And, I hate black as a color, even if it's not.
Still, I'm surprised that younger climate change activists (and even ex-engineers) arent holding rallies all over Indiana. It's incredible to me that no one's noticed this, tested the temperature differentials betwen the two colors of shrouds, calculated the exact amount of wasted KILOWATTS ( yes, kilowatts) in a day, month, or year. (A great science project for anyone with middle schoolers on board!)
As for me, we bought a '19 Coachman Class A, and I despise its black AC shroud. And, the black fan shrouds, for that matter, which sport the same problem.
I went to buy a new white one, but the price is now north of $180. Ouch!
My solution will be far cheaper. I plan to remove that Grim Reaper shroud off my rooftop. Clean it thoroughly, rinse it, then paint it with a gloss ultra white Krylon paint. Then reinstall. There will be instant energy efficiency created.
Ive even found a good paint, perfect for the task: Krylon's FUSION series paint. It sticks to plastic, has lasting fade resistance and superior adhesion.
While I haven't yet calculated the ROI from this simple energy efficiency mod, I know it will be significant. Just ask any dog who avoids walking on black asphalt in the summertime. Maybe I can start (restart) a new (old) trend.