PORTLAND — A company that has rights to develop tidal power in the nation’s northeastern corner is reporting success with its first commercial-sized underwater turbine.

Maine-based Ocean Renewable Power Company says its proprietary turbine generator unit is the largest ocean energy power plant to be installed in U.S. waters. The company says its testing shows that the 60-kilowatt unit meets or exceeds specifications for grid-compatible power.

President and CEO Chris Sauer says the system will be fine-tuned before a 150-kilowatt system is installed by the end of next year, providing enough electricity for 50 to 75 homes.

Ocean Renewable holds a license for three sites off Eastport, where twice a day the tide rises and falls 20 feet.