The Problem With Composting Toilets For Vanlife

There is no doubt that composting toilets have become a very popular toilet choice for vanlife. The word ‘composting’ appeals to many as a progressive, eco-minded method for dealing with human waste. And while composting toilets are definitely one of the best toilet options for campervans, there’s one massive caveat why composting toilets aren’t as good for vanlife as they seem. This post explains the one glaring problem with composting toilets for vanlife.

What Is A Composting Toilet?

Real quick, a definition of what a composting toilet is. A composting toilet is a waterless toilet that uses a separating tray to divert urine and solid waste into separate containers. The solid waste is mixed with a composting medium like coconut coir and can create compost.

This process only works when the urine is separated from the solids. Then the urine is then dumped separately.

What’s The Problem With Composting Toilets?

The main problem with composting toilets, as it pertains to vanlife, is that they don’t create compost fast enough. Turning human waste into compost that is safe and non-toxic takes time and a delicate balance of the right conditions.

Efficient composting requires

the right amount of moisture, but not urine because the ammonia prevents decomposition
the correct ratio of nitrogen (poop) to carbon (coconut coir, or similar)
the correct temperature for microbes to thrive
and enough time for microbes and heat to kill bacteria and parasites

It can take anywhere between 3 weeks to a year to fully compost human waste, and it depends largely on having the proper conditions.

But that presumes that you aren’t adding new deposits. And most vanlifers will be adding new material every day or every other day. So the mixture never has a chance to complete the composting process undisturbed. By the time the composting toilet is full and ready to empty, it’s simply not possible that actual nature-ready compost has been created yet.

It’s IMPORTANT that owners of composting toilets know that they cannot just empty their solids mixture into the woods. A fact that is not made abundantly clear by composting toilet manufacturers.

And if you are full-time vanlifer, then you probably don’t have a place to transfer the mixture to complete the process. You need a second container to allow the mixture to finish the composting process, either in your van, or somewhere else. And realistically, most people aren’t going to devote limited space in their campervan to a second “finishing” compost container.

If you are a weekend campervan traveler, then you could have space to finish your composting process at your house. But in that case, you might find it easier and cheaper to just use a cassette toilet, and not have to bother with separating #1 and #2 or dealing with a composting medium. You can just empty all your cassette toilet contents into your toilet at home and let it be treated by the municipal wastewater plant or your septic tank.

The most virtuous way to empty a composting toilet is to find an actively managed compost that will accept it. Some garden centers or campgrounds may have them. But at this time, it still seems like a rare and unlikely scenario for most people.

So, in actuality, most people just throw the mixture from their composting toilet in the garbage.

Trash Bag versus Compostable Bag

In the spirit of composting, some users may choose to empty their toilet’s contents into a compostable bag. Perhaps there are some compostable bags that are sturdy enough to trust for this job, but every compostable bag I have come across is weaker than a spider web.

But let’s presume that most people are like me and won’t trust a compostable bag for fear of the obvious disaster waiting to happen. That one month’s worth of poop might come spilling out onto the ground in a public place.

So most people are probably emptying their composting toilet into a regular trash bag. But there is some debate as to whether compostable bags will ever even compost in a landfill. So in the end, it may not matter much which type of bag you use.

What Happens After The Poop Is Thrown Away?

For most composting toilet owners, once they have thrown their partially composted mixture in the garbage, they are done thinking about it. But let’s follow it along to the next step. What happens to this trash bag with likely interrupted composting material?

Remember, among other things, compost requires oxygen and heat to continue decomposition. If this trash bag has been tossed into a cold environment, that could slow or completely kill the microbes in the mixture.

And what about oxygen? At first, I was concerned with whether or not trash bags or compostable bags can even let oxygen through (they cannot). That doesn’t even matter, because the conditions in a landfill are anaerobic (without oxygen).

Landfills are squashed and contained in a way that nearly eliminates all oxygen. So your poop will eventually break down in a landfill, but not through the fast, aerobic, and earth-friendly manner in which it began.

Instead, your poop will break down anaerobically over hundreds of years in a manner that creates methane (a greenhouse gas 30 times more harmful than CO2).

So what started as a well-intentioned goal to compost your waste, unfortunately falls short of that goal. Sending your composting toilet mixture in trash bags to a landfill stops the aerobic composting process.

Conclusion | The Problem With Composting Toilets For Vanlife

It brings me no joy to criticize composting toilets. Because deep down, I really want to like them. They appeal to my eco-friendly sensibilities, and beyond the scope of vanlife are definitely a step in the right direction for waste management.

But the problem with composting toilets specific to vanlife, is that they simply don’t create compost fast enough to suit the lifestyle. Many people are starting the process of composting their solid waste, only to abruptly end it as their waste goes to an oxygen-less landfill in a plastic bag.

When you consider the high cost of composting toilets, it just feels like a really expensive and complicated way to throw out your poop.

What Is The Solution?

The solution lies in our ability, as individuals or as a society, to complete the composting process. There needs to be another composting location where the semi-composted material can finish the process without new additions.

It seems unlikely that people will devote more space to a second “finishing” compost bin in their campervan. And honestly, a campervan isn’t the best place for composting in general because of dramatic temperature swings, and not to mention burning fossil fuels just to haul around a bunch of compost.

The best answer probably lies in better community composting infrastructure. People need places where they can take composting material to finish the process. It could potentially be a semi-symbiotic relationship because after all, healthy compost is a valuable resource for agriculture.

But getting to that point requires time, money, and education to transform society into one that has widespread adoption of composting.

Reasons You Still Might Want A Composting Toilet For Your Campervan

So despite all that I’ve said, there are reasons that you still might choose a composting toilet for a campervan. Because at the end of the day, there is no perfect toilet solution for a campervan.

So everyone is still choosing amongst the good (but imperfect) toilet options for campervans. Composting toilets still provide some benefits…..