Standalone

Self-contained units are installed directly in the bathroom. They are available in both electric and non-electric versions. Electric units plug into a regular AC outlet (AC/DC units also use DC electricity) to power a fan and a thermostatically controlled heating element in the base of the unit. The composting toilet is normally unplugged if it is not being used for 3 days or more.
  Composting capacity varies with the size of the Bio-drum. Electric units normally have more capacity than non-electric units because they have extra warmth and air movement.
The most important advantages of self-contained units are:

• Being waterless, they need no plumbing or water connection. Making them quick & easy to install.
• More economical than central units because there is no separate toilet.
• Better suited to winter operations than central units, because it is often easier to keep the bathroom warm.
• Most units evaporate all liquids in seasonal operation. Since the whole waste stream is recycled, government approvals are not normally required.