Compost Toilets update

In our Sustainable Sailing Book (draft under development) we have a chapter "Sorting out your poop". We believe that compost toilets are by far the best option for minimising your impact on the world around you. Not just if you are sailing, or in a caravan but for many homes as well.

The book The Humanure Handbook presents a powerful case for turning what society refers to as waste into a valuable asset. We should be moving more homes to use compost toilets (or full composting toilets). Instead of expensive sewage systems, we can simply, cheaply and safely create more fertile soil (something that is at risk all over the world).

However, using a compost toilet without a home base where the waste can be fully composted presents challenges. We should not be putting waste that can contain pathogens into rubbish bins or into the sea. Compost toilets are better than any alternative, but we still need to deal with them when they are full.

We now have a process that is working well. We can empty the solids (officially called septage) from the toilet, store for a short while and then heat them so that we kill all the pathogens (by FDA standards). They can then be disposed of safely.

We have an insulated space in the forecabin with a 150watt infrared panel heater. By putting the septage into a sealed plastic box in that space and heating it for 24 hours we exceed the FDA requirements for killing pathogens. At the moment we need to do this less than once a month and what we get out has changed dramatically. The paper is not fully composted, but the rest looks much more like soil. This is a simple process, it doesn't require much energy, it isn't messy or unpleasant.

Compared to emptying a chemical toilet, or dealing with blockages, leaks and calcified pipes in traditional boat toilets, this is a much better option. And we get no pathogens or raw sewage into the sea.