Sanergy has something along those lines http://www.sanergy.com/ http://www.sanergy.com/ However, I don't think that model fits the American mentality well. One

Sanergy has something along those lines http://www.sanergy.com/ http://www.sanergy.com/ However, I don't think that model fits the American mentality well. One more likely scenario would be the electric or gas powered combustion toilets: https://shop.ecojohn.com/products/tinyjohn-waterless-incinerating-toilet https://shop.ecojohn.com/products/tinyjohn-waterless-inciner... https://incinolet.com/ https://incinolet.com/ You see these in places where fresh water may be scarce or sewage treatment limited, e.g. a small live-aboard boat. But it's really a question of what you want to optimize for. As others have said though, a great easy addition to the current American toilet is adding a bidet.