MIT study investigates power generation from the meeting of
river water and seawater.
Where the river meets the sea, there is the potential to
harness a significant amount of renewable energy, according to a team of
mechanical engineers at MIT.
The researchers evaluated an emerging method of power
generation called pressure retarded osmosis (PRO), in which two streams of
different salinity are mixed to produce energy. In principle, a PRO system
would take in river water and seawater on either side of a semi-permeable
membrane. Through osmosis, water from the less-salty stream would cross the
membrane to a pre-pressurized saltier side, creating a flow that can be sent
through a turbine to recover power.