Commercial Composting Toilets: Envirolet v. Sunmar v. Biolet

[DirtyLittleSecret]

Been swinging the hammer over the summer, and will be putting on the siding this weekend.  
Finally the Mrs. asked the dreaded question: What about the toilet?

So, the response question is this: what will be the best unit for a small cabin that will very likely be "off grid" for periods of time (month or longer in the Winter is very possible)?  Presently I'm comparing the Envirolet Waterless Remote Units Non Electric (NE), the Sunmar Centrex 2000 NE/Sunmar Self Contained Regular NE, and the Biolet 30 NE.  

Has anyone here got experience with the self contained units?  I like the remote idea, but also fear a black bear would pull it out from under the cabin!

Links:
http://www.envirolet.com/enwatremsys2.html
http://sun-mar.com/prod_self_exce_ne.html
http://www.biolet.com/store/biolet-30-ne-c-5/biolet-30-ne-waterless-toilet-p-3

[MountainDon]

Is this a recreational use cabin like ours is, or a cabin that is lived in full time. This is important; if it's a recreational cabin, like ours, and if the weather is on the cool or cold side much of the time. Composting toilets don't compost well when the contents fall into the 60's. Composting stops dead when the temperature falls to 50 degrees and lower. Without constructing an insulated chamber for the remote units the cold weather problem will be exacerbated, in my opinion. But then even if the unit is a stand alone and inside, when the building is left unheated in cold weather there will be no composting action.

We have a standalone Sun-Mar AC/DC unit. It is used mainly in the NE mode. With out altitude and cool temperatures we may have been better served with a standard pit toilet. Or maybe even a 5 gallon bucket compost toilet. To give proper credit to the Sun-Mar it works well enough in that there have been no odors escaping from it. It has a large capacity so does not need frequent emptying. However, our cool nights and seasons means it does not compost well.

I have removed some of the mix and placed it in a barrel to see if that mix will compost down. That doesn't work well enough either. I'm thinking of building a south facing glazed lean to thing to store the drum in an attempt to use the sun to heat it up and make more effective composting. I have also emptied out the drum and incinerated the waste when we've had piles of timber slash to burn. Or you could put it in a steel drum, add diesel and burn that.

Anyhow, temperature is mentioned in a passing way, or not at all, in most of the information I recall seeing on these commercial units. It is something to consider though.

One of these would work much better in a place that had warmer weather. If there was a source of 120 VAC electricity as in being on grid the Sun-Mar AC unit would be a good choice. It has a 200 or so watt heater in the bottom. It's designed to aid in evaporation of liquids but will also lend a little heat to the drum. Not too practical for most off grid applications though.

[poppy]

Save your money, do the 5 gal. bucket. 

[diyfrank]

What exactly is a 5 gal bucket compost toilet? 
How efficient and user friendly would it be?
Would this be 1 person / 2 person size or?

[poppy]

Frank, I'm referring to the simple composting toilet as described in the Humanure Handbook, and maybe Don is thinking of the same thing.

I guess I assumed that most on the board were familiar with Humanure.  It has very good "green" concepts.

[diyfrank]

I'm not familiar with Humanure.
could you tell me,
How efficient and user friendly would it be?
Would this be 1 person / 2 person size or?
How does it compare to a chemical toilet or digging a hole?

[poppy]

Frank, I'm no expert on the subject, but intend to follow the guidelines of Humanure once I get to that stage.

Go here for more info. http://www.jenkinspublishing.com/humanure.html

[diyfrank]

That looks like a lot of reading. I'll check it out as I have time. Thanks

[MountainDon]

The 5 gallon bucket type are as user friendly as the users mindset or attitude will allow. No little miss prissy's need apply.   

[DirtyLittleSecret]

Hate to ask, but this is the place...
What would "code" require for an interior privy such as installing one of these commercial units?  Did a quick search, but found tons of info that seemed contradictory.

[MountainDon]

That would be best asked locally. What's good to go in one place may not be allowed in another.

That said though the Sun-Mar meets the required NSF code and many locations simply require the toilet to meet that code. Bruce at thenaturalhome.come has used the Sun-Mar for over a decade. You could ask them what they know about your location or help in approaching the local authorities. I don't remember if the other units have an NSF approval. You could check on them and post your finds here.