NASA has devised an innovative method called Offshore Membrane Enclosures for Growing Algae (OMEGA). It is used to grow algae, clean wastewater, capture carbon dioxide and ultimately generate biofuel without competing with agriculture for water, fertilizer or land.
The system is made up of large flexible plastic tubes called photobioreactors. They float in seawater and contain freshwater algae growing in wastewater.
Among the fastest growing plants on Earth, the algae use energy from the sun, carbon dioxide and nutrients from the wastewater to produce biomass that can be turned into biofuels and other valuable products such as fertilizer and animal food. In the process, the algae clean the wastewater by removing nutrients that otherwise would contribute to forming marine deadzone.