Tested: Compo Closet Cuddy

We were first introduced to the idea of a composting toilet in our Kimberley Karavan where a Natures Head composting loo was installed, and instantly fell in love. No more smelly chemicals, a more sustainable waste solution, no pong of human waste, and infrequent emptying. Winner!

So, when an opportunity arose to test a portable composting toilet by way of the Compo Closet Cuddy, we were all in, particularly as we were planning a remote desert adventure in a new Tvan Lightning camper. But would it be a match made in heaven?

If you are new to the idea of a composting toilet, the key differences to a chemical loo are as follows:
– It separates liquid and solid waste.
– It uses a composting medium to break down the solid deposits and an agitator (in most cases) to mix the two.
– As a waterless system, it fills the holding tank at a much slower pace than a chemical toilet, meaning significantly less time spent managing human waste.
– The solid tank does not smell.
– A low-draw fan is used to vent the solids holding tank to the outside world and helps dry out the compost.
– Being a natural product, without added chemicals, it is easy to dispose of in the bush.

From the outside the Compo Closet Cuddy looks like a portable chemical toilet. It's about the same size as a Porta Potti 365, one of the largest portable chemical pots.

It's also a handsome beast, with its squared lines and premium finish. From the front, you can see the recessed agitator handle which sits flush with the wall.

With the top lid raised, your eye is drawn immediately to the large opening. No more precision long drops down a skinny opening like a Porta Potti, that can only result in everyone’s enemy – the skid mark! By comparison, the Cuddy recess can only be described as huge.

Separating the bowl from the waste tank, two sliders meet in the middle to prevent liquid entering the solid waste tank. Liquids plus solids equals sewerage, hence the need for the separation.

Plumbing ensures urine is redirected to the front tank, but the system is not foolproof and works best if the blokes sit down on the job and the ladies direct their flow forward as best they can. In use, from a male perspective, it's not a big issue. Waking from a deep sleep with an urge to pee, you don’t have to be concerned with aiming or splatter if seated.

Lifting the seat reveals where the magic happens. At the front is the liquid storage bin which funnels through the plumbing to the storage container. We travelled across the Anne Beadell Highway during our test which has some of the worst corrugations in the country, and opted to empty the liquids waste tank each day as a preventative measure. However, as it is, there is an LED which illuminates to warn when the tank should be emptied.

An open bucket with a disposal handle fills out the rear. You can see the agitator inside which is used to mix the contents. A composting medium is added to the bucket to help break down the waste.

You can put used toilet paper in the bucket, however we chose to keep it separate to avoid bulking up the bucket. Instead, we put an extra fold in the toilet paper after each use and stored it in an opaque zip lock bag and burnt it in the evening fire.  

Compost-friendly 1-ply toilet paper is available if you prefer to keep it in the solids bin.

To prevent pong, two forms of venting are available. Firstly, a carbon filter vents within the solids container. Alternatively, a 12V fan can extract the odours to outside your tent using a ribbed hose which can help to dry out any moisture.

Vented through the Tvan's ensuite door between the zips did the trick, with a piece of stocking over the end to keep the bugs out. A 12V socket powers a low draw fan.

In transit, we stored the Compo Closet Cuddy in its travel bag at the base of the bed, covered with a blanket to minimize rub against the surrounding paintwork.

The toilet was held in place by the Tvan's tent which stores in the hatch and compresses anything stored at the base of the bed into the bed base.

When we reached our overnight camp, it was simply relocated to the tent floor and plugged into 12V power, ready for use.

The most common toilet composting material is coco coir made from coconut husks, as it keeps the product in a drier state. Peat moss is another option and is easily available from Bunnings.

We opted for the latter for our first outing, being the desert trip. It comes as a hydrated brick and must be pre-mixed with water to form a crumb-like soil.  

Care is required so not to over-wet the product. Put enough compost in the bin so that about an inch of the agitators are covered and use as required.

With much of the agitators exposed, there's risk of soiling them in use. It's not something that concerned us, but we cleaned them after our trip.

As a composting agent, we found the peat can get moist, but it will vary depending on the number of solid deposits and their viscosity. We added more pre-prepared peat a couple of times during our 17-day trip. While we fully tested the capacity of the unit during our travels, experience will educate you when to empty the unit.

We have since tested Pet Hemp as a composting medium. It's a dry product and solid deposits can resemble a panko crumbed prawn, but importantly it does the job and minimizes moisture.

During this second test, we stored the Cuddy in our second bathroom and used it there. No 12V power was supplied, relying only on the internal carbon filter. It performed as expected (no pong), with one person making almost daily deposits for 8 weeks.

It was even taken on a business trip where three blokes shared an apartment for a few days with only one combined toilet/bathroom. With the bathroom tied up each morning, it was a relief to have a back-up.

For a touring option, the coconut coir is much more compact as it comes in a hydrated brick. It works better having a bucket to mix it up in, rather than trying to do it all in the waste bucket.

For number one's, lift the lid, ensure the sliders are closed, drop your duds, find a comfortable perch and go for your life. We used a natural spray, Bosisto’s Multipurpose, to spray the urine tract after use to keep it from smelling funky. The spray is made from Australian Eucalyptus oil.

For number two’s, open the sliders, sit back, and bombs away. You can operator the sliders from a seated position which is helpful if you need to do ones and twos. 

When the deed is done, close the sliders, pull out the recessed agitator handle and gently turn a couple of rotations in each direction. Aggressively spinning the handle can lead to compost flinging around under the seat, so a measured approach works best.

Periodically, we removed the bucket and used a stick to remove the dried compost from the corners of the bin to ensure an even mix. 

The urine bottle is easy to empty: simply lift the lid to remove the container and pour it in a suitable area near a tree or in a toilet. You can choose to douse this same tree with your sink water.

The solids bucket has a handle for easy of use. Empty the bucket into a double thickness Biobag or similar which break down faster. Alternatively, dig a suitably deep hole to bury the waste.

Toilet paper should be burnt, as animals will dig up the waste and any paper quickly becomes toilet confetti littering the landscape. Ideally, any waste should have about a foot of soil over the top, to protect other visitors.

The advantages of Compo Closet Cuddy are many. Frequency of emptying is a huge factor. While the one’s do require more frequent emptying, the two’s could take weeks, depending how much use it gets.

In comparison, you might only get 2-3 days out of a more traditional portable toilet as it requires water and chemical to flush. And then a sustainable disposal location is required to empty – however RV dump points don’t exist in the bush.

Long drop toilets are not suitable as the chemical additives in a portable chemical toilet kill the natural bacteria. Without the natural bacteria doing its job, the long drop will smell and will require an expensive pump out causing the facility to close.

The Compo Closet Cuddy retails in Australia for $1495, with the storage bag another $199.95. Both items include freight. It's available for purchase online and can also be viewed at The Dirt Off Road Campers in South Australia.