VIDEO: ORPC’s TGU power systems for rivers and oceans

January 19, 2015

ORPC power systems are designed around their proprietary Turbine Generator Unit, or TGU. TGU works on the same principle as a wind turbine, with rotating foils that power a central permanent magnet generator.

There are three different ORPC’s TGU power systems: RivGen®, TidGen® and OCGen® – each designed for different installation sites.

ORPC has designed the RivGen® Power System to generate electricity at small river sites. The RivGen® can include up to several dozen TGUs, with each TGU generating up to 25kW in 2.25 m/s current. ORPC has concluded RivGen® demonstration project in the Kvichak River, approximately 440 km southwest of Anchorage, Alaska, delivering power to shore at the remote village of Igiugig.

ORPC’s TidGen® Power System, designed to generate electricity at water depths up to 45 metres, is used at shallow tidal and deep river sites. In this system, groups of TGUs connect directly to an on-shore station through a single underwater transmission line. The TidGen® is larger and more powerful than the RivGen® Power System, with each TGU having a rated capacity of 150 kW. ORPC has installed the first TidGen® at the Cobscook Bay project site, and the electricity produced from that site is being fed to the U.S. power grid.

ORPC’s OCGen® Power System, the largest and most powerful of ORPC’s modular systems, is designed for use in water depths of more than 25 metres. In the OCGen® Power System, up to four TGUs are stacked together to create larger power generating modules that are moored to the sea floor with a low-impact mooring system. A module composed of four TGUs will have a peak generating capacity of 500 kW in a 6 knot water current. ORPC concluded its OCGen® Module Mooring Project at its federally licensed site in Maine.