What is a compost toilet?

A composting toilet is a type of dry toilet that treats human waste by a biological process called composting. This process leads to the decomposition of organic matter and turns human waste into compost material. Microorganisms carry out composting under controlled aerobic conditions.

While composting has been around for centuries even in the sanitation setting, most of the US has little knowledge of a composting toilet as a proper sanitation solution. We are seeing an increase in the usage of compost toilets in alternative lifestyles, such as full-time residence in an RV, Van, Boat, or Bus. We also see them becoming popular in small spaces, remote living, and other places where running standard sewage and water lines is too expensive or simply unavailable. 

Are All Compost Toilets the Same?

While the main idea of a composting toilet, diverting the urine away from the solids, is essentially the same there are many different ways to accomplish this. There is no wrong answer, it is just what works for each individual and their space. Finding out what features are needed for you, can be quite simple. Here are some things to consider when purchasing or building a composting toilet.

Does it have an agitator? Mixing your solid waste with a compost medium starts the composting process and absorbs the odor associated with solid waste. Some toilets are set up not to agitate and use a “layering method” of compost medium + waste + compost medium. This will be a much slower process since it does not aerate the mixture well, inhibiting oxygen from the microorganisms.

Does it have a urine sensor? Once you start using a compost toilet, you will find diverting your urine into a bottle will create an odorless sanitation system and eliminate the need for a black tank, chemicals, pumps, and other products used to extract and control our foul-smelling waste. Most compost toilets will not warn you when your bottle is getting full, resulting in over-flowing and a frustrating clean-up. A compost toilet that has a urine sensor helps you worry less. Some manufacturers also offer easy-to-install drain kits that can bypass the urine bottle altogether, diverting directly into a separate tank or drain-off. You would have to check your local environmental guidelines for appropriate ways to do so.

Is it difficult to empty, use, and maintain? No, they aren’t, depending on what type of toilet is right for you.  Some compost toilets would only require a compost medium such as coco coir or sphagnum peat moss to partially fill their solids bin before use while others using the layering method would require a bag to line the solids bin. The time before needing to empty can vary from a few days (small layering method toilets) to a month (large agitation method toilets). When they do need to be emptied, a compost toilet’s solids bin can typically be easily removed, and waste can be emptied into biodegradable bags and thrown away. It can be discarded into a compost bin, the normal trash, or other waste removal locations which again can depend on local environmental guidelines. Many find compost toilets reduce the time and effort to maintain versus a cassette, incinerator, or normal RV toilets. Due to the medium and initial compost process (as well as a fan in many toilets), there should be no smell to the waste, unlike emptied cassettes or traditional black tanks.

What Are Some of the Benefits of Compost Toilets?

Water Flushed Down the Drain

There are many benefits to switching to a compost sanitation system, many are finding that while the initial investment may be costly, over time they typically pay for themselves. They are a waterless flush, which when living in an off-grid space or an area where freshwater is restricted or scarce, water becomes one of the most valuable resources. A standard RV toilet will use almost a gallon of water to properly flush solid waste into a black tank. The water used to flush household toilets is about 86.9 billion gallons of water per day in America.

Waste Not Want Not

In America, landfills take up 1.8 million acres of land and are growing. Within this acreage “An estimated 1.6 billion tons of carbon dioxide–equivalent (CO2-equivalent) greenhouse gas emissions were generated from solid waste management in 2016,” according to Intergovernmental Panel on Climate Change (IPCC). 

That is the black sludge byproduct from waste treatment facilities handling our public sewage systems. If you dump your black tank or hook up to sewage, your waste and the hazardous toilet chemicals go to these waste treatment plants, resulting in not only greenhouse gasses but hazardous conditions for landfill personnel. Regardless of lifestyle choice, this is most definitely not a sustainable solution.

Does My Waste Instantly Become Compost?

Only the permanent systems that require underground digging and installation of a composter chamber, create a start-to-finish compost cycle. For those requiring a less expensive and more flexible system, choose a compost toilet that starts the process, has the compost/waste mixture removed then added to a compost pile to finish the process.

This makes it a great fit for a nomadic lifestyle. Many states are adopting green dumpsites where your mixture can be put in a compost-friendly, biodegradable plastic bag and added to their compost system. Worst case scenario, the compost mixture from your toilet is put in a bag and thrown in the trash, although you should always check with your local environmental guidelines for proper disposal.

A Choice Today Could Change Tomorrow.

Regardless of your living space, a compost toilet could be an excellent step in the right direction for a sustainable sanitation solution.

Choosing a toilet that has features to make this choice even easier does not have to be difficult. Even electric compost toilets that would have a power agitator, will be easy to install and have very minimal amperage draw compared to any incinerator system. We see many full-time RV’ers removing their black tanks altogether and adding freshwater tanks, allowing them not only to say goodbye to dump stations but instantly double their freshwater capacity. Compost toilets are great additions to consider. Could it be right for you?