UK company CompoCloset is already known for portable toilets with particularly clean, boxy, white designs. Its latest promises to be the cleanest operator yet. A mashup of separating and auto-sealing toilet designs, the new S1 seeks to provide the best individual processing options for both urine and feces. The company calls it the world's first separating/sealing toilet, and it looks like it could be just the ticket to the ultimate off-grid toileting experience.
Auto-sealing toilets, which we recently dove into with the launch of the Wrappon Sunny, boast a simpler, cleaner way of dealing with waste when camping, boating or otherwise hitting the toilet while away from the plumbing grid. Instead of having to hold back gags while dealing with days' worth of waste, that end product is individually sealed in a baggy each and every time. The toilet does the heavy work automatically with an electromechanical system, so all the owner of said waste has to do is grab the sealed, odorless bag and drop it in the garbage, much like a mutt mitt.
While auto-sealing toilets look ideal for poop, they seem much less so for pee – liquids don't play friendly with baggies so sealing toilet designs rely on a coagulating agent to turn urine into a seal-friendly solid mass. It's a straightforward enough solution but does require quite regular use of not-inexpensive coagulant. Plus, it multiplies the number of baggies you go through, and that isn't cheap, either. Just think of how many more times you pee than poop on a given day.

CompoCloset looks to eliminate the frequent usage of coagulant and the unnecessary baggy waste by using a cornerstone feature of another style of waterless dry toilet: the separating toilet. In fact, the company is already quite familiar with separating toilets since it's specialized in them since its founding in 2020. Its Cuddy and Cuddy Lite toilets have stood as intriguing options in the portable toilet market, notable for their particularly neat-packing, boxy shapes and the electric compost agitation system in the Cuddy.
For the S1, CompoCloset uses the same simple urine solution that the Cuddy models and other separating toilets use: a bottle. The 6.4-liter S1 bottle is stored inside the toilet base, and urine gets diverted there through the drain hole in the sloped basin at the front of the toilet "bowl." This urine can simply be scattered around the ground, diluted into a fertilizer or disposed of in a toilet back home, depending on the situation. CompoCloset estimates this will save as much as 80 percent of the plastic that an auto-sealing toilet would otherwise use in sealing up both urine and stool.

Like other separating toilets, also called composting toilets, the original Cuddy toilets collect solid waste in much the same way as urine, storing it in a bin for later disposal. Users then activate the agitation system in the Cuddy or throw some sawdust or alternative desiccant atop the feces in the Cuddy Lite to eliminate odor and dry the waste out for use as a composting material or for alternative disposal. While that style of disposal sounds neater than a water-filled cassette toilet, it still requires some manual post-processing that some users would rather avoid.
With the S1, CompoCloset replaces its usual feces drying and composting process with an auto-sealing system. In fact, it's developed both a full standalone S1 toilet and a drop-in sealer kit designed to work with existing Cuddy and Cuddy Lite toilets, so current owners don't miss out on the latest toilet tech.

The battery-powered sealing unit is loaded with plastic film, which creates a bag inside the toilet bin. After one is finished going numero dos, he or she pushes the button and the system automatically heat-seals the top of the plastic to create a sealed, odorless bag that it cuts off and drops in the bin.
One could take the bag out every time, but the removable inner bin holds three to five baggies so they could also leave it until full, remove the bin and dump it in the garbage at that point – no odor, no chance of accidental spills, no having to clean out a poop bucket, and no trying to wrap one's mind around repurposing their own feces in the garden.

The onboard lithium-ion battery provides an estimated 40 uses per charge to roughly match the ~45 uses each bag cartridge offers. That means the toilet would deliver about 10 days' worth of camping use for a family of four before requiring a charge or re-bagging (assuming each person averages one bowel movement a day). The battery can wire into a van's 12V electrical system for RVing or charge via an A/C outlet.
The full S1 toilet weighs 25 lb (11.3 kg) for easy transport and has near-cube dimensions of 16.8 x 15.1 x 16.3 in (43 x 38 x 41 mm) for neat, efficient packing with cargo boxes, luggage and/or square-corner furnishings. It's designed to support over 300 lb (150 kg) of user weight.
Sure, you could enjoy comparable convenience by using a standard auto-sealing toilet only for number twos and then peeing in the bushes. But if you're camping at an event, in a parking lot, in open desert or prairie, etc, you may not have a good legal, private option. Plus, a big part of the reason to carry a toilet might be that one or more people in the group are uncomfortable with the idea of going in the wild so may end up using the toilet for both, anyway. In that case, the S1 seems like the most efficient solution, the best of both worlds.
That doesn't mean it's cheap, though. The biggest drawback of auto-sealing toilets in general is high base prices that exceed other portable toilet options multiple times over.
Perhaps unsure of what the response to this new style of hybrid toilet would be, CompoCloset has turned to Kickstarter, where the design has quickly found a strong following. Despite a pretty high buy-in, it's raised well over US$100,000 on a $15K goal, with two weeks left to go. The lowest-priced early special pledge level for a full toilet comes in at $869, a marked slash off the meaty $1,199 estimated retail price, which is about 10 times what a basic portable cassette toilet might cost you.
Those looking for just the S1 sealer unit (to use with an existing Cuddy or Cuddy Lite toilet) will find that option at the $350 pledge level.

After using a basic water-activated cassette toilet, we've been eager to try an alternative to eliminate the unsavory process of dumping and rinsing out the tank – cleaning up after a camping trip is never fun, but the cassette toilet creates a particularly dreadful task. We've long liked the clean, simple, straightforward design of auto-sealing toilets, and the S1 hybrid looks like it might be the best solution yet.
We'd prefer to skip the added plastic and coagulant usage for peeing but are in a situation with some campers who are uncomfortable going out in the bushes, so this design makes a lot of sense. We're hoping to test it out on some primitive backcountry camping trips in the future.
If and when we do, we'll report back on the results. In the meantime, happy pooping ... no matter what type of receptacle you choose or where you choose to use it!
Source: CompoCloset