ORPC demonstrates tidal power system capabilities

19 August 2010

A tidal power system developed by the Portland-based Ocean Renewable Power Company (ORPC) has successfully generated grid-compatible power from currents at Cobscook Bay in Eastport, Maine.

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

The company’s tidal generation system - designed to produce electricity at water depths of 50 to 100ft - can be used at shallow tidal and deep-river sites, and is connected directly to an onshore substation through a single underwater transmission line.

In the system deployed in Maine, a 60kW TGU has been deployed below ORPC’s research and testing vessel - the Energy Tide 2. ORPC will use the data obtained from the system to fine tune the design of its commercial TidGen Power System, which is planned for installation in Eastport in late 2011.

Over the next two months, ORPC will demonstrate how tidal energy can be delivered to the US Coast Guard for use at its Eastport station through a battery that will be charged aboard the Energy Tide 2, in a move the company says will be the first application of tidal energy by a US Federal agency.

Eventually, plans call for the commercial TidGen system to be connected to the New England grid through the Bangor Hydro Electric Company system.

A single TidGen system has rotating foils that power a central permanent magnet generator

Through a three-year partnership with the University of Maine (UMaine), personnel at ORPC are also observing the marine environment around the Beta Power System. UMaine researchers, led by Dr Gayle Zydlewski, are supervising the programme, which incorporates visual and acoustic monitoring technology.

The data collected will allow UMaine and ORPC to better understand and help minimise any potential interaction between ORPC’s technology and marine life.