Rebecca Norman wrote:I agree that on the one hand, it's such a daily resource that there's hardly a need to store it up. On the other hand, plants don't want to be fertilized in the winter. And midwinter is when our dry composting toilets start to leak at the bottoms a bit -- icicles! because in summer there's more drying action naturally in the toilet than in winter. And for the third reason, in winter some people are less inclined to go all the way out to the toilet outhouses in winter nights, so collection in containers tends to happen, so of course one thinks of storing it till the growing season.

However, urine tends to precipitate white hard salts that look like plants wouldn't like them. Presumably would be worse on drying. And the smell of stored urine, I think it starts turning into ammonia, is really really strong and only gets stronger. The ammonia is volatile (thus the smell) so as liquid urine dries you are losing the nitrogen and creating a nuisance. And finally, to dry down such a watery liquid would take a huge amount of either heat or air exchange, and doesn't really sound very viable.

These days I've been thinking that a huge pile or container of sawdust would probably be the best way to store urine of winter through till summer. As compost of course. It would need to be really huge, I think.