The document discusses osmotic power, a renewable energy technology that uses osmosis to generate electricity. It summarizes that osmotic power was first invented in 1973 and has since been researched by various scientists. The document then provides details on how osmotic power works using a semi-permeable membrane and the difference in salt concentration between freshwater and seawater to create pressure. Finally, it analyzes the efficiency and design of different types of osmotic power plants, along with the technology's advantages of being renewable and having low environmental impact, though it is currently very expensive.