Here’s what seawater desalination actually costs in 2026, before anything else:<\/p>\n
Those ranges are wide because seawater desalination cost is highly site-specific. Feed water salinity, required output quality, local energy prices, pre-treatment needs, and whether the system needs to be containerized for remote deployment all move the number.<\/p>\n
Ocean water typically runs 32,000\u201338,000 ppm TDS. Brackish water runs 1,000\u201310,000 ppm. Seawater RO (SWRO) requires operating pressures of 800\u20131,200 psi. Brackish water RO (BWRO) operates at 100\u2013400 psi. Higher operating pressure means heavier pressure vessels, more powerful pumps, and more energy \u2014 all of which add cost.<\/p>\n
Drinking water requires less than 500 ppm TDS. Industrial applications \u2014 pharmaceutical, semiconductor, power generation \u2014 may require TDS below 10 ppm, which typically means a second-pass RO system. A two-pass system can cost 40\u201360% more than a single-pass system at the same flow rate.<\/p>\n
Ocean water is biologically active and contains suspended solids, algae, and seasonal turbidity variation. Pre-treatment for SWRO typically requires multimedia filtration, ultrafiltration (UF) membranes, and chemical dosing. In regions with high biological activity, the pre-treatment system can represent 20\u201325% of total project cost.<\/p>\n
On large SWRO systems, energy recovery devices (ERDs) \u2014 pressure exchangers or turbochargers \u2014 capture energy from the high-pressure reject stream and transfer it back to the feed water. ERDs reduce energy consumption by 30\u201350% on systems above roughly 10,000 GPD. The device itself adds $15,000\u2013$200,000 to equipment cost, but payback is typically 1\u20133 years.<\/p>\n
| Component<\/th>\n | % of System Cost<\/th>\n | Notes<\/th>\n<\/tr>\n<\/thead>\n | ||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| High-pressure pump<\/td>\n | 15\u201325%<\/td>\n | Largest single component cost; multistage centrifugal or positive displacement depending on flow rate<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||
| RO membranes<\/td>\n | 20\u201330%<\/td>\n | SWRO membranes (e.g., FILMTEC SW30XHR) cost more per element than BWRO membranes; replace every 3\u20137 years<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||
| Pressure vessels<\/td>\n | 10\u201315%<\/td>\n | Must be rated for 1,000+ psi for SWRO; fiberglass composite standard, stainless steel for harsh environments<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||
| Pre-treatment (filtration, chemicals)<\/td>\n | 15\u201320%<\/td>\n | Higher for surface seawater with biological loading; lower for clean offshore intakes<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||
| Controls and instrumentation<\/td>\n | 10\u201315%<\/td>\n | PLC-based control with remote monitoring standard on commercial and industrial systems<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||
| Frame and housing<\/td>\n | 5\u201310%<\/td>\n | Containerized housing adds cost but enables rapid deployment<\/td>\n<\/tr>\n | ||||||||||||||||||||||||||||
| Installation<\/td>\n | 10\u201320% of equipment cost<\/td>\n | Varies widely by site \u2014 offshore and island installations significantly higher<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\nOperating Cost: The Number That Matters Long-Term<\/h2>\n |
| Parameter<\/th>\n | Seawater RO (SWRO)<\/th>\n | Brackish Water RO (BWRO)<\/th>\n | Municipal \/ Low-TDS RO<\/th>\n<\/tr>\n<\/thead>\n |
|---|---|---|---|
| Typical feed TDS<\/td>\n | 32,000\u201342,000 ppm<\/td>\n | 1,000\u201310,000 ppm<\/td>\n | 100\u20131,000 ppm<\/td>\n<\/tr>\n |
| Operating pressure<\/td>\n | 800\u20131,200 psi<\/td>\n | 100\u2013400 psi<\/td>\n | 50\u2013150 psi<\/td>\n<\/tr>\n |
| Energy use<\/td>\n | 3\u20136 kWh\/m\u00b3 (with ERD)<\/td>\n | 0.5\u20131.5 kWh\/m\u00b3<\/td>\n | 0.2\u20130.5 kWh\/m\u00b3<\/td>\n<\/tr>\n |
| Typical TDS rejection<\/td>\n | 99\u201399.8%<\/td>\n | 95\u201399%<\/td>\n | 90\u201398%<\/td>\n<\/tr>\n |
| Membrane type<\/td>\n | FILMTEC SW30XHR or equivalent<\/td>\n | FILMTEC BW30 or equivalent<\/td>\n | Low-pressure RO or NF elements<\/td>\n<\/tr>\n |
| Recovery rate<\/td>\n | 35\u201350%<\/td>\n | 60\u201380%<\/td>\n | 75\u201385%<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\nApplications<\/h2>\nAMPAC USA Seawater Desalination Systems<\/h2>\nAMPAC USA has manufactured seawater RO systems in Pomona, California since 1993. The product line spans from 100 GPD marine watermakers to 250,000 GPD industrial SWRO systems. Every system ships factory-tested with documented flow rate and rejection performance. FILMTEC SW30-series membranes are standard across the SWRO line \u2014 the same membranes used in large municipal desalination plants worldwide.<\/p>\n Systems are available as skid-mounted, trailer-mounted, or ISO-containerized configurations for rapid deployment to remote sites. Custom engineering is available for non-standard feed water chemistry or site-specific installation requirements.<\/p>\n |