So then, can you pee in a compost toilet? The simple answer is 'yes'. There are two main types of composting toilet model – one has a separate tank for urine (urine-diverting) and the other does not with all waste going in the same tank.
Urine is full of nitrogen, which is actually beneficial to the health of a compost pile. Too much urine, however, can make a pile too wet and slow down decomposition. To maintain the right amount of moisture in the pile, composting toilets deal with urine by evaporation, leachate drainage, or urine diversion.
In healthy populations, urine is sterile, and removing it from feces makes composting the solids easier and more effective.
Urine can act as a starter for a compost, encouraging the decomposition process, such as adding urine to a pile of leaves.
Urine, too, is a great compost stimulator. Obviously, the stiff shot of nitrogen and a bit of moisture both help, and the uric acid (urea) is also very beneficial. Uric acid levels are said to be the highest in the morning, so that's the best time to rain down on the compost pile.
Six months at cool room temperature is the current aging recommendation from the World Health Organization. Large-scale agriculture is eager to develop urine-based fertilizer systems, which have additional environmental benefits. Less water is needed for flushing, and less dirty water enters the waste stream.
Benefits of urine on compost
Human urine is beneficial as part of a composting system as it has a high nitrogen content along with containing potassium and phosphorus. These three are the main nutrients that are essential to healthy plant growth and ones that you see referred to as NPK on plant fertilizer labels.
Many gardening and composting sites recommend adding urine onto compost heap to help speed things up. With cold composting this provides the bacteria with a source of food which can be digested quickly producing heat rapidly.
Because Diarrhea typically has a little more liquid in it than normal 'poop' you may find you might need to run the exhaust fan a little more than you would normally to help evaporate the additional liquid. Other than that, your composting toilet should function as normal, without any issues.
Yes, you can. You don't have to think twice if it is a urine-diverting system as mentioned above. Otherwise, sit and relieve your pressure to avoid sending liquid into the solids bin.
The simple answer is NO - composting toilets do not smell. Now, in saying that there are a couple of caveats to this. A composting toilet that is properly maintained does not smell so if there is a smell coming from your composting loo, this is likely an indication that something is wrong.
Excessive amounts of urine will add too much nitrogen, slowing decomposing. Adding pee to a compost pile too frequently will result in a build-up of salts in the compost, which can lead to a toxic environment for the microbes doing the decomposing, slowing, or stopping the composting process.
That being said, as a general rule, you would want to remove compost at least once a month if your toilet is used residentially, and once a season if used occasionally or on weekends.
Urine can also speed up the chemical process in the compost heap, making it a better fertiliser to help grow vegetables and save even more energy in reducing food miles. Male urine is better than female urine because it is slightly less acidic.
Your Compost Smells Like Ammonia (Urine-like)
If your compost pile smells like a backed up outhouse toilet mid-August, then it's very likely that the pile has too much nitrogen ("green") materials for the amount of carbon ("brown") to properly aerate and break down.
Urine is rich in nitrogen and phosphorus and has been used for generations to help plants grow.
Excess urine in the soil can introduce toxic levels of nutrient into the soil and thus kill the plant as seen in the case of urine fertilizer; the large amount of nitrogen is the main concern. A rule of thumb is that the toxic level of nitrogen is approximately four times the normal fertilization rate.
Human urine provides an excellent source of nitrogen, phosphorous, potassium and trace elements for plants, and can be delivered in a form that's perfect for assimilation. With a constant, year-round and free supply of this resource available, more and more farmers and gardeners are making use of it.
On a hot day, the plants will wilt easily, and require frequent watering. With such a constant throughput of water, diluted urine can be applied as frequently as 3 times per week. For use on containers, urine can be diluted with water at the rates of 3:1 or 5:1 and applied once, twice or three times a week.
Dilute one part urine to 10-15 parts water for application on plants in the growth stage. Dilute in 30-50 parts water for use on pot plants, which are much more sensitive to fertilisers of any kind.
As a general rule for home garden use, dilute 'fresh' urine with water 3 or 4 parts to one, mixing only as much as you will use that day. Dilute 10 to one, for very young or delicate plants. It is recommended that you use this as an occasional fertilizer, not more than twice a week, and not every time you water.
The pile should not be directly exposed to sun, wind, rain, nor sited in a low-lying place subject to unnecessary dampness and standing water. Strong sun not only dries, but also is hostile to micro-organisms.