A Maine company that wants to build underwater river turbines as an alternative to diesel generators used in remote villages in Alaska is ready to begin testing a prototype.

Ocean Renewable Power Co., based in Portland, says its RivGen Power System was built with backing from the Alaska Energy Authority and the Denali Commission.

It’ll be installed in July on the bottom of the Kvichak River to generate power for a community of 50 about 250 miles southwest of Anchorage.

Company officials say it will meet half of the community’s electricity needs.

The company also is testing units off the Maine coast. The company’s first underwater turbine began delivering electricity to the Emera Maine power grid in 2012.