| Electric Macerating Toilet | Electric pump moves water and shreds waste before discharge. | Approximately 0.5–1.5 L (0.13–0.40 gal), depending on the flush control and bowl rinse setting. | Typically 15–25 A while the pump is running on a 12 V system. | Approximately 10–20 seconds. | Yes; the built-in cutter reduces solids before discharge or transfer. | 12 V wiring with an appropriately sized fuse, seawater or freshwater supply, discharge hose, holding tank or approved overboard discharge system, and proper venting. | Strong waste transfer, compact plumbing options, and good compatibility with holding tanks. | Higher startup current, audible pump noise, and more moving parts that require periodic service. | Cruising boats that need reliable waste transfer through relatively long or complex discharge runs. |
| Electric Centrifugal Toilet | A rotating impeller uses centrifugal force to move rinse water and waste. | Approximately 0.5–1.5 L (0.13–0.40 gal) per flush. | Typically 10–20 A while operating on a 12 V supply. | Approximately 5–15 seconds. | Limited or none, depending on the pump design; it is not the same as a dedicated macerator. | 12 V circuit, water supply, discharge plumbing, holding tank or approved discharge route, and access for pump maintenance. | Fast flushing, relatively simple operation, and efficient water use when correctly adjusted. | Can be more sensitive to foreign objects, hose restrictions, and pump wear than a macerating design. | Day boats and small cruising boats with short, direct discharge plumbing. |
| Low-Water Electric Toilet | Short electric flush uses a small quantity of water to rinse the bowl and move waste. | Approximately 0.3–1.0 L (0.08–0.26 gal) per flush. | Typically 10–20 A during the flush cycle. | Approximately 5–15 seconds. | Usually integrated with a small macerating or transfer pump; confirm the specific design before installation. | 12 V power protection, reliable water supply, correctly supported sanitation hose, holding tank capacity, and adequate tank venting. | Extends holding-tank capacity and reduces freshwater or seawater consumption. | Insufficient rinsing can increase bowl residue or odor if the flush setting, hose routing, or tank ventilation is poor. | Boats where holding-tank capacity and water conservation are important. |
| Vacuum-Assist Toilet System | A vacuum pump creates negative pressure and moves waste through a small sanitation line; the pump may operate from 12 V. | Approximately 0.2–0.5 L (0.05–0.13 gal) per flush, depending on the vacuum valve and system settings. | Typically 10–25 A when the vacuum pump runs; total system demand varies by pump and control configuration. | Approximately 3–10 seconds, plus time for the system to rebuild vacuum. | Usually no built-in maceration at the toilet; a separate treatment or transfer pump may be required. | Vacuum pump, vacuum-rated sanitation hose, control wiring, holding tank, tank vent, and accessible service points. | Very low water consumption, small-diameter plumbing, and flexible toilet placement. | More components, additional installation complexity, and dependence on a properly sealed vacuum system. | Larger boats or multi-head systems where low water use and flexible plumbing are priorities. |
| Electric Flush Valve Toilet | An electric valve releases rinse water while a separate pump or gravity path carries waste away. | Approximately 1.0–2.5 L (0.26–0.66 gal) per flush, depending on valve timing and water pressure. | Typically 5–15 A for the valve and pump combination; the actual load depends on the transfer arrangement. | Approximately 5–15 seconds. | Normally no; waste movement depends on gravity, a separate discharge pump, or the vessel's plumbing layout. | Pressurized freshwater or seawater supply, 12 V control circuit, discharge plumbing, holding tank, and appropriate anti-siphon protection where required. | Simple user controls, clean bowl rinsing, and the ability to use a separate waste-transfer arrangement. | May use more water and may require extra equipment if gravity drainage is not possible. | Installations with an existing pressurized water system and straightforward waste routing. |
| Manual Toilet with 12-Volt Conversion Pump | A manual bowl is paired with an electric pump or conversion assembly for powered waste transfer. | Approximately 0.5–2.0 L (0.13–0.53 gal) per flush, depending on the pump and water-control settings. | Typically 10–20 A while the conversion pump operates. | Approximately 10–20 seconds. | Often yes if the conversion pump includes a macerator, but this must be verified for the selected assembly. | Compatible bowl and pump assembly, 12 V fuse and wiring, sanitation hose, holding tank or approved discharge route, and adequate service access. | Can reuse an existing bowl and may reduce replacement cost or installation changes. | Compatibility, mounting, hose alignment, and available service space can vary significantly between installations. | Refit projects where an existing toilet bowl and mounting position are being retained. |
| Selection Notes | Actual current draw, water consumption, noise, and flush duration vary by pump design, hose length, lift height, water source, and control settings. Size the 12 V circuit using the toilet manufacturer's specified fuse, wire gauge, and maximum operating current. Use only approved marine sanitation hose, provide proper tank venting, and follow local regulations for overboard discharge. |
