Systems
Water
Make fresh water, anywhere.
A water system is the equipment that produces and treats potable water onboard, turning seawater into safe drinking water through reverse osmosis and downstream treatment.
At the heart of the system is the reverse-osmosis watermaker: a high-pressure pump forces seawater through a semi-permeable membrane that rejects dissolved salts and most contaminants, leaving fresh product water on one side and concentrated brine on the other. The trade-off in any RO system is energy. Pressurising seawater is demanding, and on a battery-powered vessel or expedition vehicle every amp-hour counts. Energy-recovery designs address this directly by reclaiming pressure from the outgoing brine stream and feeding it back into the feed side, cutting the power needed per litre produced. The result is more water for the same draw on the bank, which matters most on sail, off-grid and long-range platforms where generator runtime and solar are the limiting factors.
Drinking-water treatment is the second half of a complete system. Watermaker product water is low in dissolved solids but still benefits from defined treatment for taste, storage and biological safety, and any vessel or vehicle also carries tank or shore water that needs the same protection. Treatment covers filtration, disinfection and stored-water management, and the right approach depends on the source, how long water sits in tanks and the standard you need to meet. PowerSol carries Spectra Watermakers for reverse-osmosis and energy-recovery desalination, and the Katadyn Group for water treatment, giving a path from raw seawater through to verified potable supply.
Specifying a water system is a question of balance between output, available power, space and maintenance. Membrane production is sensitive to feed-water temperature and salinity, so real-world output varies with where and how the vessel is used. Installation also matters as much as the unit itself: clean, well-supported plumbing, a protected intake, accessible pre-filters and a sensible service position all determine whether the system performs and stays reliable over seasons rather than weeks.
How to choose
- Size output to demand, not maximum capability. Estimate daily consumption per person, add a margin for guests and washdown, then choose a unit that meets it within a comfortable daily run window rather than running flat out.
- Match the watermaker to your power reality. On battery-led, solar or sail platforms, prioritise energy-recovery designs that produce more water per amp-hour; the lowest purchase price is rarely the lowest cost over the life of the system.
- Plan the install around servicing. Pre-filters, membranes and the high-pressure pump all need routine access, so position the unit where filters can be changed and the system flushed without dismantling joinery.
- Protect the membrane with proper pre-filtration and flushing. Sediment and biofouling are the main causes of premature membrane failure; a clean intake, staged pre-filters and a fresh-water flush regime extend membrane life considerably.
- Treat the whole water path, not just the watermaker. Pair RO production with appropriate filtration and disinfection for tank and shore water so every source delivered to the tap meets the same drinking-water standard.
Brands
Water brands
Water — FAQs
What is an energy-recovery watermaker and why does it matter?
It is a reverse-osmosis desalinator that reclaims pressure from the brine being discharged and returns that energy to the feed side, reducing the power needed to produce each litre. On battery, solar or sail-powered platforms this means more water for the same draw on the bank, which is often the deciding factor on off-grid and long-range vessels and vehicles.
How much water can a watermaker produce?
Output depends on the unit chosen and on operating conditions. Membrane production varies with feed-water temperature and salinity, so a given watermaker yields more in warm tropical water than in cold. Size the system to your estimated daily consumption plus a margin, and confirm expected output against the specific model and your intended cruising area.
Do I still need water treatment if I have a watermaker?
Yes. Watermaker product water is low in dissolved solids but treatment still has a role for taste, stored-water management and biological safety, and any vessel or vehicle also carries tank or shore water that needs protection. A complete system pairs RO production with appropriate filtration and disinfection across all sources.
What maintenance does a marine water system need?
The main tasks are regular pre-filter changes, fresh-water flushing of the membrane, membrane care or replacement over time, and servicing of the high-pressure pump. Keeping the intake clean and following the manufacturer's flush and lay-up routine is the single biggest factor in membrane life, so plan the installation so these jobs are easy to do.