Now stretch it actually exhausting and rapidly maintain it to your higher lip, which is delicate to temperature. You’ll really feel that it is hotter than it was earlier than. That is since you’re including vitality to the rubber band, which will increase its temperature.
Are you prepared for the superior half? Hold it stretched for a short while till it returns to room temperature. Now let the rubber band calm down and rapidly contact it to your lip once more. It is now colder than room temperature! Critically, do this for your self.
So for those who had a sufficiently big rubber band, may you utilize this to chill your own home? Wait a minute, you are gonna say: Within the first stage, once we stretched the rubber band, it bought sizzling, after which it cooled again to its unique temperature—and in doing that it heated the air. You are proper. However what if we may vent that hotter air exterior? Then you could possibly hold simply the cooling section inside.
Increase. You simply re-invented the air conditioner! As a substitute of a rubber band, an AC has a fluid known as a refrigerant that circulates in a closed loop from inside to exterior. This fluid has a low particular warmth, so it adjustments temperature rapidly, and a really low boiling level—turning right into a fuel at one thing like –15 Fahrenheit.
How’s it work? The fuel is first compressed, inflicting it to warmth as much as like 150 levels. The new fuel circulates in a set of copper coils exterior, with a fan blowing over them, so the fuel loses thermal vitality to the ambiance. (Copper additionally has a low particular warmth.)
Then it is pumped again inside, the place the stress is rapidly lowered, inflicting it to broaden and immediately cool right down to one thing like 40 levels. Because the now chilly fluid circulates by way of indoor coils, a fan blows heat inside air over it, heating the fluid once more and cooling the indoor air within the course of. Because the system circulates, it mainly picks up thermal vitality indoors and carries it open air.
By the way in which, that is precisely the identical course of that your fridge makes use of to maintain your cheese and soda chilly. In each instances, the method makes one thing inside cooler and one thing exterior hotter. Put your hand behind the fridge and you may see what I imply. Oh, only for kicks, here is a man who really constructed a fridge that runs on rubber bands.
So Warmth Pumps Aren’t New!
You thought this was going to be an article about warmth pumps, proper? Effectively guess what. We have been speaking about warmth pumps this entire time, as a result of they run on the identical ideas. A warmth pump cools your private home similar to an air conditioner, by circulating a refrigerant and ranging the stress to vary its temperature, so it takes thermal vitality from one place and places it in a distinct place.
So again to the large thriller: How can a warmth pump improve the temperature of indoor air on a chilly day with out really producing any warmth? Easy: Simply run it in reverse! This time we let the new compressed refrigerant cool off inside the home to boost the indoor air temperature. The low-pressure, chilly fuel then goes exterior to heat up.
Heat up exterior? Yep. Even on a freezing day, the air nonetheless has thermal vitality. As long as it is above absolute zero—which, imagine me, it’s, since that is round –460 Fahrenheit—the air molecules are in movement. And since we’re cooling the refrigerant to, say, –15 levels, which is decrease than winter temperatures in most locations, it should wring thermal vitality out of even frigid air.
After all, you may’t get vitality without cost. Warmth pumps depend on electrical energy to drive the compressor and followers. However in case you have photo voltaic panels at residence, or if the electrical energy in your space is even partly from non-carbon sources, changing a fuel furnace with a warmth pump could make a giant distinction in decreasing greenhouse fuel emissions. And it will in all probability decrease your utility payments within the course of.