With a composting toilet, instead of sending waste into the sewer system or a septic tank, it is instead stored and broken down through an aerobic process by bacteria in a closed system. Composting toilets produce carbon dioxide and water vapor as byproducts. Over the period of a few months, waste is broken down into a substance called humus, a mature form of compost that can act as a form of fertilizer.
Composting toilets do not require any water to function, so they are ideal for remote locations that do not have access to city or abundant water supplies. They can cut water consumption and are an eco-friendly option for a home or business. The composting system is virtually odor free. Toilet paper is safe to use in composting toilets; the carbon in the paper helps with the composting process. Over time, the waste in the system breaks down to a much smaller volume in size, which makes for easier disposal. The resulting humus has no odor, and, when added to soil, can add much needed nutrients and improve water filtration and retention.
To vent the carbon dioxide produced by a composting toilet, you need to install an exhaust system. The aerobic bacteria that break down the waste work best in warm temperatures. If you live in a cooler climate, installing a heater could be necessary to keep the toilet working. Because oxygen is vital to the bacteria's function as well, a rotating drum or other system to turn the waste and to ensure oxygen reaches it at all levels is also needed on some systems. If food waste is introduced into the composting system, it can attract both fungus and insects.
Small portable composting toilets are available for use when camping or traveling through remote areas. They often require periodic access to a power source for their internal heaters to function. Before installing a composting toilet in your home or business, research the laws and regulations for your area. They are forbidden in many areas. The use of humus on crops for human consumption is illegal in most parts of the U.S., and your area could forbid its use on other types of plants as well.