CS Composting Toilet - no drain field, low energy consumption

The Sun Frost CS composter system incorporates a sleek interior toilet and two 55 gallon batch composters outside to finish the composting process. Food scraps increase biodiversity and actually makes the composting process more effective.

The Sun Frost CS composting system does not require a drain field or have large electrical requirements to evaporate liquids. The only electrical requirement is about 2 watts for a ventilation fan. The fan can be provided in DC for solar applications or AC for grid tied installations. Odor in the bathroom is controlled by two methods, covering the toilets contents with saw dust or peat moss and a fan powered ventilation system. Even without a ventilation system, covering the content of the toilet with sawdust has proven itself effective. For many years, a similar home built toilet system outlined in the “Humanure Handbook” effectively utilized this strategy. With the incorporated ventilation system the Sun Frost CS is even more odor free than a conventional toilet, since the odors produced while using it are expelled directly outside.

For a single user exclusively using the CS it will take about 1 week to fill the 5 gallon interior storage container. If only solid waste is added the toilet will take more than 2 months to fill the interior container.

With this batch composting system one exterior drum is filled while the composting process is completed in the second drum. The 55 gallon composter only requires the addition of a dry material, such as wood savings. Wood shavings are readily available in feed and pet stores. Effective composting requires aeration (mixing), proper moisture content and warmth. Mixing in the 55 gallon drum is easy with the stainless steel “cork screw” type mixer provided with the kit. The exterior drums are also insulated to keep the compost warm, which speeds the composting. During winter months under very cold conditions the contents of the drums may freeze. Human manure and food scraps can still be added to the drum, composting will continue during warmer weather. A scoop, provided with the kit, makes emptying the drums a simple matter. When emptied the contents of the drum smell and look like healthy top soil.

We have had the contents of these drum composters tested for fecal coliform and have found the level to be extremely low. The secret of making safer pathogen free compost is keeping the process aerobic, which is achieved by mixing and adding sufficient dry material. The open top drums for the 55 gallon composter can be obtained locally. This significantly reduces shipping costs. Included with the Sun Frost CS are insulation and insulated lids .

Other composting toilets with a small foot print do not provide outside composters to finish the composting process; it would be up to the home owner to provide a sheltered composter to complete the composting process. The Sun Frost CS is easily assembled and provides a convenient way to compost all of a households organic waste.

“there were more than 20,000 days of closings and advisories in 2005, at ocean, bay and Great Lakes beaches.” The bulk of these closings are the result of improperly operating sewage treatment plants and septic systems.

The EPA estimates that each year, one billion gallons of raw sewage are dumped into U.S. waters. That is 3000 gallons for each person in the United States. Composting toilets could conserve water and change this hazard into a valuable resource.

Control of Pathogens
A unique feature of the Human Humus Machine & the CS composting system is that the compost can be pasteurized before it is removed from the composter. The temperature needed to attain pasteurization depends on how long that temperature is maintained; pasteurization can be accomplished at 130°F for 3 days or at 180°F for 10 minutes.

When the composter is filled and about 10 pounds of easily compostable material such as unbleached flour, cottonseed, or alfalfa meal are added, temperatures high enough for pasteurization can be obtained.

Even without pasteurization, we found that the level of E. coli in the compost was low enough to allow its use as a soil amendment. The EPA has developed standards for acceptable levels in sewage sludge. Sludge is the solid material settled out in a sewage processing plant. The un-pasteurized compost we tested had an E. coli levels five times lower than the standard set by the EPA for use as a soil amendment.

To be extra cautious, we recommend that the finished compost not be used on crops that are uncooked or are in direct contact with the soil.