In 2020, a three-turbine frame was lowered into New York City's East River; six months later, it had sent 210MWh of tide-...
In October 2020, workers lowered a strange metal frame into New York City's East River. It held three underwater turbines, each shaped a bit like a boat propeller. Six months later, the turbines had produced 210 megawatt-hours of electricity. According …