The paper presents the latest developments and field experiences made with the large area, high rejection FilmTec((R)**) SW30HR-380 and SW30HR-320 membrane elements and focuses on technical-economical considerations with special emphasis on energy consumption and possible operational savings. Fouling incidence and latest developments on technical remediation, particularly in relation to the large spacer SW30HR-320 new membrane elements for open intakes are reviewed as well. It is concluded that the new products discussed represent a good tool in designing seawater for clean and fouling RO feed. The technical-economical analysis shows that with this element it is possible to operate with savings in the order of 20% for the installation costs, up to 25% for energy consumption and up to 4% for cleaning costs including plant down time costs in the case of the FilmTec SW30HR-320 operating on waters with high fouling potential.