Wave Power in New York:

The East River is many things. If Verdant Power has its way, add to the list: "source of electricity." Verdant has installed underwater turbines in the East River in an effort to harness the power of the underwater current, but it has not been easy. Today's New York Times reports on the company's travails.

Weeks after they were formally dedicated by Mayor Michael R. Bloomberg, six underwater turbines that turn the river's currents into electricity have been shut down for repairs and a basic redesign. The East River's powerful tides have been wreaking havoc with the giant turbine blades since the first two were installed in December.

"But the good thing is that there's more power in the East River than we thought," said Mollie E. Gardner, a geologist for Verdant Power, which owns the equipment.

This is the reality of new energy projects, which often seem more attractive on paper than they do in practice. Verdant's principals, along with the state officials who have supported the project with large grants, say the setback is only temporary, even expected — a way to work out the kinks before moving onto the next, expanded phase.

Despite a string of mishaps that has taken a bit of the luster off the project, there is still sufficient optimism about tidal power to attract investments, and even some old-fashioned competition.

It is interesting that the biggest obstacle to Verdant's plan is not NIMBYism or excessive regulation, but the East River itself. Building turbines that can generate power and remain in operation has apparently been a challenge. It also does not help that much of the underwater work on the turbines has to be compressed into short windows when the river's current subsides.

Like virtually every viable source of power, the underwater turbines may yet raise environmental concerns, as it is unclear whether turbine installation impacts fish populations.

Mr. Taylor said the company has had to spend more than $2 million to study the impact that the turbines might have on fish in the East River. The water is monitored 24 hours a day with sonar equipment to see whether fish are harmed by the blades, which move at a comparatively languid 32 revolutions per minute.

The company has found that the few fish who are picked up by the sonar tend to swim around the blades.

"So far, there haven't been any strikes," said Ms. Gardner, the geologist who works for Verdant.

Still, federal regulators want Verdant to conduct studies on species like sturgeon and some turtles that are rarely seen in the East River.

If the kinks are worked out, and the fish seem okay, Verdant hopes to install 300 turbines in the East River. This would generate enough electricity to power 8,000 homes, according to Verdant's estimates, and likely bring the power cost down to a competitive price.