Wool and Water Skeptics
21 April 2023 --- Ralph
This is an exchange between Ralph and one of the people who was skeptical of a video presented on our page describing wool's ability to handle water. This exchange took place on YouTube. I won't be surprised is there is a lot more of this!
@XXXXX: Let me get this straight: you’re implying wool, creating heat when it’s wet, ought to be warmer when it’s wet than if it’s dry?! This is contrary to all experience. Weatherwool is a great product but there’s no reason to be silly.
@WeatherWool: Did you watch the vid? Contrary to what experience? --- Ralph
@XXXXX: Ralph, I love WeatherWool and I admire you greatly for your passion, your vision, and your exemplary determination in the face of many setbacks caused by the pandemic. But I have never in my life been warmer in wet clothes than in dry clothes, no matter what the clothes were made of.
As wet clothes dry, heat is being used to supply the energy necessary to make water change its phase from liquid to gas-so anyone wearing the drying clothes will experience cooling, not warming. Where is that energy coming from if not from the person wearing the wet clothes? As you know, the energy must come from somewhere. If it was being drawn from the water, or the wool itself, those things would get cooler, not warmer.
I propose a different experiment: take two tubs of water at room temperature. Have a temperature probe in each tub. Then add some wool fabric to one of the tubs. If your theory is right, the tub with the wool should warm up. I don’t think it will.
@WeatherWool: I appreciate the kind words ... but it still seems like you may not have watched the vid, or the followup vid that helps to address skepticism.
This reply is long, and may be interesting to others, so I'm going to reproduce it on the WeatherWool website. I won't use your YouTube handle, tho, to help preserve your anonymity.
First, your points:
POINT ONE: "As wet clothes dry, heat is being used to supply the energy necessary to make water change its phase from liquid to gas-so anyone wearing the drying clothes will experience cooling, not warming. Where is that energy coming from if not from the person wearing the wet clothes? As you know, the energy must come from somewhere. If it was being drawn from the water, or the wool itself, those things would get cooler, not warmer.”
RESPONSE TO POINT ONE: I don't understand why you bring up "wet clothes drying". That's irrelevant to the experiment. But I will point out the wool can obviously pick up heat from external sources. I'll also point out that the rate at which the wool might (eventually) draw heat from the wearer would seem critical. But the subject is clothing. And so what counts is the subjective experience. Many times I’ve been out in cool and cold weather, wearing wool that had been exposed to water, and never have I felt the wool chilling me. This drew me to wool as a youngster. Something else … biological systems are full of conditionals and feedback loops. For example, hemoglobin is well known to release oxygen where it is needed. If you don’t mind, I’ll toss out a thought for which I have seen no scientific investigation. I would not be surprised if wool somehow “knows” when it’s time to dry. Perhaps the wool fiber squelches evaporation until appropriately triggered.
POINT TWO: “I propose a different experiment: take two tubs of water at room temperature. Have a temperature probe in each tub. Then add some wool fabric to one of the tubs. If your theory is right, the tub with the wool should warm up. I don’t think it will.”
RESPONSE TO POINT TWO: I thought the wool would warm the water in the tub, and it did. But this is also irrelevant because we don’t wear wool for swimming. Neither do sheep, as far as I know. Wool serves sheep, and us, by shedding liquid water (the exocuticle is hydrophobic) and by absorbing and adsorbing water vapor (hydrophilic internals). The heat generated by wool, in a natural setting, warms and dries the air around the wearer, and quickly sheds the liquid water from a dunking. Wool is not designed to warm a tub of water, which has a far higher specific heat than air.
Because your channel seems to be anonymous, I don't know if you've ever actually had any of our wool. And of course I don't know what your above-referenced clothes have been made of.
One of the reasons I started WeatherWool was my dissatisfaction with other woolens.
Here’s what I think/believe, and I could be wrong.
What matters is subjective experience. (Repeated for emphasis.) Wear some serious wool, jump in a river on a cold day, and see for yourself. Or, not so intense, go out in cold rain for a while. But do it in serious wool (see below).
Here is some more info as I understand it. And I think the wool industry ought to be all over this!!
A great many of the "woolens" on the market aren't even truly wool, in my book. Most woolen garments have liner fabrics. So, they don't count. Also, very frequently, "wool" fabric has a significant amount of cotton. Anything made with cotton doesn't count. Also frequently, woolens are superwashed, and they don't count either. [Our Fabric is made with superwashed warp (FullWeight has about 10% -- by weight – superwashed, and MidWeight about 30%.), but never superwashed weft. I'm hoping to eliminate all superwashed with our upcoming Batch 9.]
I studied a lot of science in school. Although I was a very poor student, I learned a few extremely valuable lessons:
- Nature doesn't care what people think. Whether or not people think something "makes sense" is immaterial. If Nature seems “nonsensical”, the observer doesn’t understand
- Biology (I studied mostly bio) is complex in the extreme. Such complexity might seem nonsensical, except it works, and it seems Nature’s designs are actually as simple as possible. The complexity within every cell in our bodies makes our cell phones look like child’s play.
- Biological designs are exquisitely sophisticated and complex, but always for a reason. And this is proved by testing that is both remorseless and relentless.
Those concepts, plus lifelong experience with woolens, guide my approach to observing and trying to understand wool.
So, here’s some stuff I have learned from experience in wool, and from reading some of the research (but I haven’t found much). Also, talking with hundreds of people about wool, I’ve learned about the general public’s knowledge and perspective.
Most people don't understand what it means for wool to be "wet". I think it’s because people don’t wear much wool anymore, and because most of the wool we do wear is not what I would consider serious wool. We tend to relate our experiences to fabrics made of other materials, but the behavior of wool is different.
People wear a lot of cotton. Nature made cotton to disperse seeds -- a purpose completely unrelated to protecting a mammal from the weather. People also wear a lot of synthetics. But as mentioned, our top-end technology is trivial compared to Nature. And so my point of view is that Nature’s solutions, if we can borrow them, will outperform happenstance (cotton) or human invention (poly- blah-blah, microfleece, etc., etc.)
The outer layer of wool fiber is hydrophobic ... it is very well known to REPEL liquid water. But interestingly, the same fiber has small (SMALL!!!) openings that will admit water vapor. And the internals of a wool fiber are hydrophilic. Wool internally bonds the water molecules, releasing heat as it does so. The literature also says that INSIDE the fiber, water vapor can condense back into liquid, releasing a LOT more heat. Our factories can’t make anything like that, as far as I know. But also, here’s the “wet” part … it’s easy to find references that claim wool can hold 30% of it’s weight in water before it is saturated. But the saturation occurs internally, and the water is kept off the skin of the wearer. So … wool can be completely saturated and still be dry to the touch. And because it is dry to the touch, there is no water contacting the body. Water will chill a person dozens of times more quickly than air. So, even saturated wool does not chill the wearer. That might seem nonsensical double-talk to people who don’t know wool. So, again, get out in some serious wool and see for yourself.
@WeatherWool: THANKS for another reply. And THANKS for the extremely kind words regarding your AAJ, and of course for working with our little company in the first place.
BUT ... (knew that was coming), it still seems you are missing the point ... or maybe adding a point we didn't make. Going back to the start. If you pull your jacket out of the closet, and subject it to water (dunk it, spritz it, wear it in higher humidity), it WILL produce heat. You can very easily test this yourself, and that was one reason we published the simple-test video. Or, we can send you some scraps and even a test kit, which we are thinking about offering anyway. This exchange makes me think that would be a good idea! But you can also do a little web-searching. We are hardly the only ones claiming wool plus water yields heat.
We didn't make any claim that the wool would endlessly produce heat. We also didn't claim that it violates physical law, or that it wouldn't at some later point absorb energy in releasing water and drying. My basic claim is that wool protects in wonderful ways, and one of those ways is that it produces heat when you need it (when you encounter water). BUT actually, your reference to thermodynamic law does have me thinking ...
Again, based on personal experience in wool, the marvelous sophistication of bio systems AND the evident evolutionary success of wool, I am guessing wool will employ methods of regenerating its heat-production capacity WITHOUT needing the sheep to provide the energy for liquid--to-gas phase change. I wonder if, for example, the wool fiber somehow excretes liquid water, rather than host the liquid-to-vapor phase change? That would save a lot of energy. How or even IF this could happen I don't know and cannot suggest a mechanism. And at a micron-level, I don't even really understand the difference between liquid and vapor. I mean, how many water molecules need to clump together before you have a liquid? I was surprised to read that you can have liquid water inside a fiber that is only 21 microns in width. But that's just my human-scale "common-sense" experience leading me to hold incorrect assumptions. Does the definition of vapor specify individual water molecules only? Same with the hydrogen bonds formed by adsorption of water to the wool fiber's internal structures. Perhaps there is an exogenous event or energy source that breaks the water-wool hydrogen bond in a way that costs less energy than was released when the bond formed.
Or maybe it's just that the design of the wool keeps the hydrogen bonds and liquid water in place until conditions are favorable to the sheep.
Believing that something can't happen because we THINK it would violate physical law might indicate a lack of understanding on our part. Nature is full of strange and surprising truths.
Thanks for the input and thanks again for working with us --- Ralph
21 April 2023 --- Ralph