The Italian-made Schenker Watermaker (above), which PS endorsed in the April 15, '02 issue, isn't included in this round-up of reverse-osmosis watermakers, though it is still made. Shown here is a modular unit. The smallest one can produce over nine gallons per hour.

Reverse-osmosis watermakers have long been available for boats, but until a few years ago, they were bulky, power-hungry machines that were barely suitable for the typical cruising sailboat. All that has changed in the last decade or so, and relatively efficient, reasonably compact reverse-osmosis watermakers are now readily available. In the seven years since Practical Sailor last evaluated DC-powered watermakers, there has been slow but steady development in this niche of the marine market.

The trend today is toward higher-output, energy-efficient, more automated watermakers. At the same time, some of the original, dead-simple machines—or their lineal descendants—are still available. This look at today's watermaker market will help you decide if a…