PORTLAND, Maine (AP) — Energy officials in Maine say a tidal power project is delivering electricity to the U.S. power grid for the first time.

Bangor Hydro Electric Co. operates the grid where the tidal power connects. It says Portland-based Ocean Renewable Power Co.'s first underwater turbine was delivering to the grid the first commercially produced tidal power on Thursday afternoon.

Ocean Renewable president Chris Sauer says it's a "historic moment."

The first underwater turbine generator unit has rotating foils that lend the appearance of a manual reel mower for cutting grass. It was installed last month in Cobscook Bay and can keep the power on in 25 to 30 homes.

The pilot program calls for more units off the Lubec and Eastport region at the nation's easternmost tip within four years, producing enough power for 1,000 homes.

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