In 2020, a three-turbine frame was lowered into New York City's East River; six months later, it had sent 210MWh of tide-made power to the U.S. grid

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 to the U.S. Department of Energy, this was a new U.S. record for production of marine energy. It also showed something bigger: the ocean’s tides can quietly help power a modern city.

How three turbines turned water into power

The project is known as RITE, which stands for Roosevelt Island Tidal Energy Project. It is located in the East River, a tidal strait that separates Manhattan from Queens. What makes the East River special is that its currents flow in the opposite direction four times a day due to the tides. The company behind it is Verdant Power, which came up with a system called the TriFrame. It consists of three turbines on one metal frame, which allows all three turbines to be removed or installed at the same time. If the water flow is strong enough, the blades rotate like an underwater mill. Whenever there is a change in the direction of the flow of water, the turbines change their direction. The Department of Energy states that the plant operated above 99 percent availability within the first six months, with water-to-wire efficiency exceeding 46 percent. The department also notes that RITE operated under the very first hydrokinetic pilot license FERC ever issued for a tidal energy project, a milestone that made it, by regulatory definition, both a licensing first and a demonstration-scale pilot. The electricity generated here did not remain in the laboratory; it instead found its way into the Con Edison local network grid, which powered the area of Roosevelt Island and Manhattan itself.

Why this record actually matters

While solar power is ineffective at night, and wind power dies down on calm days, tides aren't affected by either. Tides are influenced by the position of the moon and the sun; therefore, their occurrence can be predicted long ahead of time. This is one reason why tidal power is gaining attention as a steady partner to solar and wind. A 2025 review published in the journal Marine Development puts that 46 percent figure in context, explaining that tidal energy stands out among renewables mainly because of this predictability. It notes that tidal energy systems with proper installation can achieve an efficiency rate of 30-50 percent, which is the same level of efficiency found in onshore wind energy systems, meaning RITE's own performance sat comfortably within, and toward the higher end of, that range.

Not just New York's story

The East River is small, but it points to something larger. Coastlines across the globe are home to powerful tides that are currently underutilized for generating energy. Ocean energy, including tidal and wave power, could reach a global market of 350 gigawatts by 2050, according to a 2023 report from IRENA and Ocean Energy Europe. That same report notes that tidal stream technology, like that at RITE, is among the ocean energy technologies closest to market-readiness. That frame is important for those who care about climate change. It shows that clean energy can come not only from large solar and wind farms but also from water flowing past a city every day.

The catch: Tidal power has a long way to go

However, none of this means tidal power will replace solar or wind any time soon. It's expensive to build and maintain underwater turbines, and there aren't many places where the currents are strong enough. The Marine Development review also finds that the levelized cost of tidal stream electricity, estimated at between 27 and 51 cents per kilowatt-hour, is still well above that of solar or wind. Turbines must also be designed by engineers to withstand saltwater, storms, and years of wear, all while not harming nearby marine life. RITE was intended to serve as a demonstration rather than a power generation plant. It operated on a pilot license and was decommissioned in December 2021 after its license expired, having delivered more than 312 MWh to the grid over its full run.

What does this mean for you

You'll probably never see the turbines on the East River, but the concept behind them is worth remembering. The rivers, straits, and coastlines of a city are not just scenery. They carry energy every day, even if nobody uses it. It took only six months, three turbines, and 210 megawatt-hours to show that tidal power works. The bigger question now is how quickly the world catches up with it.