SoylentNews is people
SoylentNews
The flu season arrives so predictably, and affects so many of us, that it's hard to believe that scientists have had very little idea why cold weather helps germs to spread.
...
the answer may have been lying invisible in the air that we breathe. Thanks to the laws of thermodynamics, cold air can carry less water vapour before it reaches the "dew point" and falls as rain. So while the weather outside may seem wetter, the air itself is drier as it loses the moisture. And a steady stream of research over the past few years has shown that these dry conditions seem to offer the perfect environment for the flu virus to flourish.
...
That's counter-intuitive – we normally think that the damp makes us ill, rather than protects us from disease. But to understand why, you need to grasp the peculiar dynamics of our coughs and sneezes. Any time we splutter with a cold, we expel a mist of particles from our nose and mouths. In moist air, these particles may remain relatively large, and drop to the floor. But in dry air, they break up into smaller pieces – eventually becoming so small that they can stay aloft for hours or days. (It's a bit like the mist you get when you turn a hose pipe to its finest spray.) The result is that in winter, you are breathing a cocktail of dead cells, mucus and viruses from anyone and everyone who has visited the room recently.What's more, water vapour in the air seems to be toxic to the virus itself. Perhaps by changing the acidity or salt concentration in the packet of mucus, moist air may deform the virus's surface, meaning that it loses the weaponry that normally allows us to attack our cells. In contrast, viruses in drier air can float around and stay active for hours – until it is inhaled or ingested, and can lodge in the cells in your throat.
(Score: 3, Insightful) by Snow on Tuesday October 20 2015, @08:52PM
I read the third paragraph, and they make the claim that you will 'feel' warmer, but the link offers no actual data/evidence to how that translates into a significant (or even insignificant) cost saving.
(Score: 1, Troll) by frojack on Tuesday October 20 2015, @09:11PM
Because. You will be satisfied with 65 degrees, rather than cranking it up to 75.
You know, some things don't need links. Some things have been known for hundreds of years before the phrase "citation needed" was coined.
No, you are mistaken. I've always had this sig.
(Score: 3, Insightful) by Snow on Tuesday October 20 2015, @10:06PM
I disagree that this is one of those things that doesn't need proof. You made a claim that increasing your humidity will lower your heating bills. I'm countering that the change would be insignificant or even a net increase in heating bills.
Some googling brings up this answer that asserts that humid air at 25 degrees C will take ~3.6% more energy to heat than dry air:
https://physics.stackexchange.com/questions/45349/how-air-humidity-affects-how-much-time-is-needed-for-heating-the-air [stackexchange.com]
Now, room humidity is not set to 100%, more like 40%, so that 3.6% turns into 1.44%... but... we also need to remember that it's cold outside and natural humidity is near 0, so we have to add the water to the air manually, and that takes energy in the form of evaporation. A 1500 square foot bungalow has about 280 m^3 of air @ 1.2 Kg/m^3 = 336kg of air. Let's say we are trying to achieve .75% absolute humidity (roughly 40% relative at room temp), so that is 2.52 KG of water suspended in your house. It takes 2260 Joules per gram of water to evaporate it, so... 2.52*1000*2260 = 5695200 joules = 1.58200 kWh.
It takes 1211 joules to heat one m^3 of air one degree, so 380*1211*20 degrees = 9,203,600 joules = 2.56kWh
So... IF you start with dry air @ 0% humidity. It would take 2.56kWh to heat it to room temperature. If you add water to the air, it takes 4.14kWh to get that air to room temp (but you also have to heat the water up in addition to evaporating it, and that works out to another 100,000 joules = .027 kWh, so 4.16kWh)... Which is 61% more energy than if you just needed to warm the dry air.
Now, you only have to evaporate the water once, then just maintain the heat, so that is a factor. This also doesn't include humidity from daily living (showers, cooking, breathing, etc) which is essentially free humidity.
I guess in summary, my point is that it takes a significant amount of energy to add humidity to the air. I am skeptical that the lowering of the thermostat by a couple degrees would have enough energy savings to significantly offset the amount of energy you are spending to evaporate the water.