So an alternative to making the tumble dryer "smarter" can be to simply not use it for most of the time, thereby cutting the loss caused by "dumb" dryers.
The engineering part that's missing is related to re-introducing and improving the many awesome laundry line systems that used to be available.
Where I grew up if you left the clothes out (but covered with inclement weather), depending on season, they would either dry perfectly or get a funky (awful) smell to them. I wish we had a drier back then, it would have made my teenage years less embarrassing.
I think I’ve seen the kinds of indoor drying lines you are perhaps referring to, but I don’t know how compatible they are with Northern Europe.
I'm Polish and we've always had a dryer at home, no idea how my mum would have gone through that pile of loundry she always did otherwise. So YMMV.
And the problem in the UK is that relative humidy is so high you literally start getting mold inside your house if you just use an airing dryer, as most people do, a lot of houses have that characteristic "musky" smell because they are just too damp. In poland the air is a lot dryer(especially in winter!) so you don't get this problem.
1. We don't expect solids to evaporate, because it's not something we notice often (though if you think about the fact that a few inches of snow can disappear in a couple of days while the temperature remains below zero Celsius, you suddenly realize that you do observe it if you live in a cold climate)
2. We're so accustomed to using heat to speed the evaporation of water. So we might assume that removing large amounts of heat energy will "stop" evaporation. Or at least cause it to slow so much that air drying becomes impractical.
But ice does, indeed evaporate (to be accurate, it sublimates). My question is how temperature affects the speed of evaporation at low temperatures. How long do you need to leave your wet clothes hanging below freezing before they are dry?
https://phys.org/news/2018-10-sublimation-solid-ice-quickly-...
I might try this out on the deck next season but I don't assume ice is just going to sublimate away because it's literally outside all winter and doesn't go anywhere.
Although most people have a freezer that needs to be deiced occasionally.
Particularly, if they have an ice cube tray in their freezer... and, somehow, the ice cubes in the tray slowly shrink.
And when they do freeze it's not like cloth encased in ice, it's more like the clothes still look and feel dry - they just hold their shape :) If you put them at room temperature they finish drying within minutes.
The loss that TFA and smart dryers are trying to cut is time spent on laundry. Having lived both with and without a tumble dryer, I'm very skeptical that there's a laundry line system out there that is less time consuming than even a dumb tumble dryer.
If there is one, I'd love a link!
You put your clothes there, and the next day they are dry.
Other common solution is collapsible drying racks on your balcony: https://images.morele.net/i256/12998234_0_i256.jpg
Or just clothes lines (but usually people have some backup in case it rains).
I've never seen people use powered dryers for clothes. And we get our share of rain, and in the winter it gets to -20C sometimes.
If you have working ventillation you're fine either way. If not - you're not. In fact I'd expect worse problems if you evaporate that same water quicker, because there's less time for it to escape outside.
In contrast, my grandmother lives in a village with such incredible rainy seasons, that this has been a pain point as perpetual as the rain itself. For a few months in summer, the air is so humid that even unused clothes have trouble stay dry. Condensation appears on the wall, and nothing ever dries, no matter where you hang them; indoors, outdoors, doesn't make a difference. Sometimes, they have no dry clothes for weeks during summer.
For some items like wool underwear and t-shirts I hang inside because sun bleaching can be a problem.
I live in a desert, and my current place has a not-tiny yard, so I'm curious about this. Anyone got examples or pictures of laundry line systems they really like?
I've seen many great things in photos where laundry lines are strapped out between windows and across streets "ad hoc". But most of them were in photos. I think the "pulley" that carries the line and the line itself seem to be more durable than what my local building market sells... I can only get nylon lines and small pulleys, so I'm not happy with the projects I've done so far. The best lines I've found are the ones with metal wire inside.. the ones without metal in them break very quickly.
One that I would really like to have is a strong, durable multi-line rack that sits below a window. If possible, I'd like to be able to expand and contract it.
There's also a lot of ideas shared online for creative indoor solutions.
In general, Pinterest is the place to go.
Indoors: https://www.houzz.com.au/magazine/designs-for-living-10-dryi...
Regarding crinkly clothes: generally if you hang up a wet shirt to dry, it gets less crinkly than in a tumble drier. That's an old tip for reducing ironing efforts :)
Regarding "hard" towels etc: This one is really difficult, especially terrycloth and similar material that's supposed to be very soft can seem hard after air drying. You can try to add vinegar as a softener if your water is hard, I find that makes a good improvement. And you can generally rub clothes soft - I tried folding towels and give it a good rubbing, works well to soften them up. I would also remark that after using a soft towel once and drying it, the terrycloth also becomes hard :)
If you're even lazier you can get a combo washer/dryer. Not quite as effective as a separate dryer but it's nice to have dirty clothes go in and clean, dry clothes come out without a middle step.