2:26pm

Thu June 23, 2011
Old tech, new tech

Rochester one step closer to lighting library with old millrace

Hydrokinetic turbines are, as a City of Rochester PDF once put it, a "newly expanding technology." They're not your grandpa's hydropower: they don't require dams, falls or other big chunks of infrastructure.

All you need to make a hydrokinetic turbine happy is a current - be it from a rushing river or, in the case of Rochester's central library, an old 19th century millrace that flows underneath the stacks.

Way back when, that old millrace used to power flour mills along the Genesee River. Now, the City of Rochester wants to put it back to work. City engineers think one or more hydrokinetic turbines in the millrace could create enough electricity to keep the library's lights on.

On Tuesday night, City Council approved funding for the project's first step - a preliminary study to see if those city engineers are right.

Underwater windmills

Rochester City Engineer Jim McIntosh says the easiest way to think of a hydrokinetic turbine is to think of a partially submerged windmill.

"Basically, [imagine] a paddle that is sitting in the water and the water moving by spins the paddle and generates the power," says McIntosh.

The city's goal is to generate electricity by sticking a few of those "paddles" in the old millrace. The power expectations are modest, but McIntosh says it's a green energy project worth pursuing.

"If we could do that and capture and store enough power to maybe run the lights on the library and offset some of our expenses at the library, that would be a good thing," says McIntosh.

The preliminary study will cost the city $40,000. McIntosh says there's no estimate at this point of how much the project will cost in total, but a 2009 estimate from the city put the price tag at $500,000. McIntosh says the preliminary study will determine how many years it will take for the project to pay for itself in cost savings. The study will also identify what outside sources of the funding it might be eligible for.

No word from the city on when the turbines might actually be spinning. But McIntosh says if this project ultimately proves successful, the city might be able to use the technology at other raceways around town.