Clothes detergents have been able to effectively clean in cold water for decades. The only reason people still wash using these detergents in hot water is ignorance. It's such a huge waste. Please stopping washing clothes with brand name detergents using hot or warm water. It costs more money, does more environmental damage, and doesn't even make your clothes marginally cleaner.

Ignorance? I doubt it. There's a variety of reasons to wash at least some items in very hot water. Killing dust mites for people with allergies sounds like a good reason. Getting rid of faecal contaminants sounds like another good reason. It does way more than making clothes "marginally cleaner".

Modern detergents are capable of doing these jobs in cold water.

Not commenting to argue either way, as I have no idea what the truth is. But, I’m surprised that there can be such strong, confident, and basically contradictory opinions on this topic which seems to me like it ought to be a simple matter of fact.

As someone who has done laundry before, I feel confident in chiming in here: Anecdotally, hot water is almost always better for reducing smells in my clothing. It helps some fabric types more than others, but it doesn’t hurt any of them.

If you can afford a home, electricity, water, detergent, and clothing, I personally cannot imagine a single reason not to use hot water.

The specific detergent does matter quite a bit here, as well.

If you really want to get something very clean then add 1/4 cup of Borax and use Extra Hot if your washer supports it. Source - me - I wash household blankets the kids make super dirty sometimes. If the material can handle the heat (no shrinking or delicate materials issue) then the Borax really does super charge the detergent effects somehow.

I don’t doubt there might be something environmentally problematic with Borax but I just am not aware myself.

I’ve also done plenty of laundry, of course, but I never bothered varying the water temperature as an independent variable.

I had a girlfriend years ago who insisted that cold water worked just as fine as hot water. While I didn't write down any observations, I did do several loads of laundry over the next couple weeks where I adjusted water temp as a variable, and found that things typically smelled more fresh when they were washed in hotter water.

Maybe it's placebo, maybe it's my detergent, maybe it's something else, but for me, personally, I always wash non-delicate laundry with hot water because at the very least, I feel like I smell better, and that's worth it to me! :)

My clothes will not get cleaned and still smell bad if I wash them in cold water with major brand detergents.

My dishwasher uses 1kwh of power per load, thats hardly worth capturing

Shower tho… esp if you purchase ready made shower capsule that does not require external hot water supply and produces it’s own from recycled water? That might be the one.