It includes a new "optimized turbine," which is smaller and has fewer parts than the ones it initially used, Taylor said.
The appeal is that, unlike a dam, turbines can be installed and removed quickly.
"You can put in two or three turbines a week," he said. "It's like planting trees."
The new design also includes a gravity-based anchoring system. Rather than being secured to the bottom of the river, three turbines will be set on a triangular frame that sits underwater.
Verdant is planning to submit its final license application to federal regulators in the next couple of months - the last step before the turbines can be installed, Taylor said.
"The regulatory process is very slow," he said. "Because we're putting something in navigable waters, there's a lot of competing interest."
When the licensing process is complete, Taylor said, Verdant plans to research sites on the Hudson River and the Long Island Sound for similar hydroelectric power sites.
The company would install 30 turbines in the East River, and be able to generate 1 megawatt of power. That's enough to power 30,000 homes. The test system had powered a Gristedes supermarket on Roosevelt Island but the new system is substantially different than the test units - both in terms of a reduced number of parts in the new system and that it would be held in place by gravity alone.