This may all seem anal and tiring, but if you really want to avoid your home smelling like a dumpster, then you better shape up and not throw your trash all around as if your home is a dumpster. Be responsible of your trash for your own sake, or don't be and suffer the consequences.
The automatic model is sensor controlled and has a lid which quickly opens when the trash bag gets about 10 inches and 130 degree angles from the can's sensor. With normal usage, the power will last about 6 months with 4 D-size batteries. For those that do not require trash bags, the inner bucket can be easily removed and cleaned when the trash is removed and taken out.