COLUMBUS (AP) - Energy researchers say the winds blowing across Lake Erie can power wind turbines, but the project won't be cheap.

A study released Friday showed it will cost $77 million to $92 million to build several turbines and a nearby wind research center to be run by Case Western Reserve University. Earlier estimates had put the price tag at about $60 million.

The world's first freshwater turbines would stand some 260 feet above the water level and produce up to five megawatts of power each - enough to power up to 5,000 homes. Visible from downtown Cleveland, they would be built 3 to 5 miles offshore.

Europe already has wind farms in shallow ocean waters off Denmark and the United Kingdom. The United States' first ocean-based wind farms are expected to begin operating in shallow waters off Atlantic Coast states in the coming years.

The study, commissioned last year by the Great Lakes Energy Task Force, was conducted over the course of a year by German research firm Juwi (pronounced joo-VEE) International. It's the first step in a slow march toward harnessing wind power in Cleveland. Proponents say the pilot project could create thousands of manufacturing jobs and rejuvenate the financially ailing city.

"We want to remake Cleveland as a green city on a blue lake," said Cuyahoga County Prosecutor Bill Mason, the task force chairman.

The U.S. has no offshore wind production, although projects are in the works for Atlantic waters off Delaware, New Jersey and Rhode Island.

The task force will gauge community interest in the turbines over the coming months while seeking federal funding and private investment, Mason said. Officials hope to have the first turbines in place by early 2011.

Building turbines in the water costs two to three times more than it would cost to build them on land, Mason said. Behind the scenes in the U.S. and in Europe, the race is on to build the world's first deep-water wind farms, ones that would operate on floating platforms in waters hundreds of feet deep, like oil rigs found in the North Sea and the Gulf of Mexico.

Cost estimates for the turbines ranged from $91.4 million to erect eight turbines generating 2 1/2 megawatts of power each to $77.2 million for three larger turbines that would produce five megawatts each.

"Looking from the shoreline, they're probably about the size of the tip of your thumb," Mason said.

Opponents say anchoring large wind farms on the bottom of the Great Lakes would have implications for commercial and recreational navigation, water quality, fish habitat and even flight patterns for birds and aircraft.

The study recommends building the turbines on eastern parts of the lake based on factors such as wind power, shipwrecks, water depth and shipping channels. A cone-shaped ice deflector would help break up sheets of ice, though energy production won't be as prolific during the winter months as ice will obstruct service vessels from navigating the lake.

The environmental impact on birds and other wildlife would be minimal, the report said. Habitat loss would mostly result from birds avoiding the turbine locations, and it's unlikely the turbines would affect migration patterns, as few birds fly near the area.

The risk of water birds colliding with turbines is low, the report said.

The report identified some ecological concerns, including fish and coastal current disruptions around turbines and the effects of electromagnetic fields on fish. Part of the lake bed would be lost during turbine construction, but research indicates turbines can provide artificial reef that enhances the marine habitat, the report noted.