Composting toilets save energy and water through using aerobic composting of your pees and poos. So now you know!
The idea is simple. A collecting chamber under the toilet seat collects the excreta. After each use bulking material like coconut coir or peat moss for example are thrown on top.
This ensures that air spaces remain, essential for an aerobic process to take place. An odorless compost should result, usable as a soil additive.
You can either build composting toilets yourself or choose one of many manufactured models.
Compost toilet design knows many variations but all try to maximise aeration and warmth to keep the compost process going.
This can include using worms in the mix. Poor things you say? Well, that's what they love to do...
Is this new technology?
No, 'course not. The general idea has been around for thousands of years. China's cabbage farming, for centuries, depended on 'humanure'-collecting companies who sold it back as compost to grow more, and bigger, cabbages.
Is there a connection with that distinctive cooked cabbage smell? No, I don't think so.
But the contemporary compost toilet comes from Scandinavia, in the 60's. The Americans and Canadians then took this up in a big way and it has taken off in Australia.
Benefits of composting toilets
A regular toilet flushes between 10 – 18 precious litres of potable water down into the sewerage system every time a toilet is used. With a dry compost approach none. And you save on your water bill.
It takes energy to run our waste water treatment plants. In the US they account for about 3% of the national electricity load. So, you may have a PV solar panel to save electricity but had you thought of this energy-saving area?
You can add your vege peelings, grass clippings and waste paper to your compost chamber and produce the best compost for your garden.
Imagine if everyone had composting toilets. Instead of power-hungry, smelly waste water treatment plants we'd be producing rich compost for building soil, maybe for community gardens.
Yes, there are some and you should know about them before installing a composting toilet. In the main the disadvantages crop up if you do not do this properly.
The construction must be done correctly. It must be properly connected to a gray water system to minimize pollutants and filtration, to keep airflow up, is important in avoiding any odor issues.
When your regular flush toilet has a defect you get the plumber but with this one you must maintain it yourself. If you don't you could be inviting health issues and messy clean-ups.
Ongoing management: making sure that the right materials are mixed in, the material composts thoroughly and does not cause disease issues later.
In a commercial composting toilet a power outage becomes a problem because the unit will stop working. Over a longer period it can build up gas. Phewww...
That brings us to the question...
Do they smell?
No, apparently if correctly installed they will not smell. The occasions that it might will be due to incorrect use, installation or overloading of the system.
So, if large numbers of unexpected visitors, send them to the neighbors or don't feed them! No, sorry, there are actually systems that will easily cope with this.
Well, what do you mean with "cost?" Savings to the environment?
If financial cost, then they will cost you much more than a regular flush toilet if connected to sewerage. Compared to a septic system they are generally much cheaper. But all that depends on your local conditions.
Health department approvals
Various local authorities and health departments have different rules, knowledge and experience with composting toilets. Ask the relevant authorities where you live.
Various types are available.
In batch systems a container, full of composted waste, is simply exchanged for an empty one. Some come in a carousel system which holds a number of containers. A new one is swung into place as the full one comes out.
In a continual process system new waste pushes down the composted waste where it is collected.