I'll push back on this:
> Hot water is a must for cleanliness
This is simply not true. Our bodies are good at self cleaning and cold water is fine for washing off surface dirt. Hot water is actually deleterious to our skin & hair (not evolutionarily designed for it). Cleanliness problems will come from wearing unwashed clothing, particularly cotton clothing (wool can absorb human sweat for some time without becoming smelly). And obviously it's good to have water to wash around the private parts but again, cold water is just fine for this.