Wednesday, September 12, 2012
In Quest for River’s Power, an Underwater Test Spin
Could cars in New York City someday run on electricity generated at the bottom of the East River?
Trey Taylor thinks so, but first he and his associates have to build a better turbine — specifically, one that can withstand the river’s strong and shifting currents. On Tuesday afternoon they moved one step closer to their goal, as a crane hoisted what looked like a giant, hand-held electric fan from the riverbed east of Roosevelt Island.
The turbine — its three white blades were still turning as they broke the surface — had been bolted for 10 days to a piling drilled into the bedrock beneath the river. Mr. Taylor’s company, Verdant Power, had positioned it there in the latest test of its long-running plan to turn the tides into a source of electricity.
“This is the perfect testing ground,” said Dean Corren, the company’s director of technology, as he watched two divers descend from a barge on a ladder and attach a sling to the turbine. The current, which runs as fast as 2 meters per second, keeps the blades spinning slowly, except during the lulls when the tide reverses its flow from north to south, or back again.
The turbine, a commercial prototype with a diameter of more than 16 feet, did not generate any electricity during its brief period of submersion. A previous set of turbines in the river powered a Gristede’s supermarket and an adjacent parking garage on the island, Mr. Taylor said.
The problem with those machines was that they kept breaking, he said. So, the company commissioned the manufacture of stronger blades, made of layered fiberglass and plastic, and tested them first in a lab in Golden, Colo.
After 10 days in the river, the blades gleamed in the September sunlight, showing no obvious signs of wear or damage. The turbine’s pristine appearance brought smiles to the faces of Mr. Corren and his colleagues. Dean Whatmoor, a logistics manager, who had been monitoring the test from a converted cargo container filled with computer screens and gauges, admitted that he was a little sad to see the test end.
The next step will be to start building more turbines and installing them in the river in sets of three, Mr. Taylor said. The rotors are made in Holland, Mich., but the other parts will be made in New York State and assembled in Bayonne, N.J., he said.
In about five years, the company hopes to have 30 turbines arrayed in the river, each capable of producing 35 kilowatts of electricity. All told, the project would produce about as much power as one wind turbine, enough to power a few hundred homes.
Mr. Taylor said he has had discussions with the corporation that operates Roosevelt Island and officials from Cornell University, which plans to build a school of applied sciences on the island, about how the power from the turbines might be used. One idea he has broached, he said, is installing charging stations for electric cars on the island.
“New York City could be the first city with tidal-powered cars,” he said.
But Verdant Power, which has raised about $33 million from investors, has a potentially more lucrative plan: to sell its technology for use in rivers and even oceans around the world. “The holy grail is to harness the ocean tides,” Mr. Corren said.
Simply turning the East River into a viable source of electricity would be a vindication for Mr. Corren, who began researching the idea as a student at New York University in the early 1980s, and wrote his thesis on global warming. The university later eliminated its applied sciences department and gave up on the tidal turbine technology developed there, Mr. Corren said.
On Tuesday, he grinned at the prospect that his work at N.Y.U. three decades ago might yield a renewable source of power for the campus that Cornell is building, which city officials hope will be an engine of New York’s economic future. (In April, N.Y.U. announced plans to develop its own applied science campus, in Downtown Brooklyn.)