As we begin our journey through the wonderland of environmentally-friendly toilets, let's start by cataloging the main technologies available.
Vacuum toilets use little or no water. You may have used them on aircraft or on ships. Perhaps a bit overkill for an island summer home, but is most like the toilet you have at home.
Composting toilets take waste and collect it for decomposition. There many ways to collect, and many ways to decompose. Some methods are more attractive than others, to put it mildly.
Incinerating toilets burn waste in a very high-temperature process. Good news: all that icky stuff is quickly and permanently gone. Bad news: giant, expensive, power-hungry combustion chamber right between your legs.
More detailed posts on each type- complete with photos!- to follow.