Rooftop turbines will be more efficient than solar panels for one Yonkers co-op.
After rebuilding its roofs and completing numerous green projects, the board at Kimberly Gardens co-op in Yonkers has ventured onto a new frontier — installing wind turbines on one of its three roofs.
Windy epiphany. “We asked ourselves how we could continue to make the buildings go green,” says board president Robert DiMartini. “We talked about installing solar panels on the three rebuilt roofs, but with the help of our energy consultant, Chris Schiller at Resolution Energy, we realized our location is more conducive to wind power than solar power.”
Schiller told the board that a wind turbine would use less roof space than solar panels, would cost less up front and would have a quicker return on investment. The board was in.
A reliable source. So instead of installing solar panels, the board is using just 400 square feet on the roof of one of the six-story buildings to install a 12-feet-tall, 10-feet-wide array of wind turbines, called a WindWall, manufactured by American Wind in Hunstville, Ala. The wall of 108 turbines rotates as the wind shifts, maximizing energy production, and it operates around the clock.
Just as solar panels need a steady diet of sunshine, turbines need a dependable breeze. Kimberly Gardens was in luck. “This part of Yonkers has an average wind speed of 10 m.p.h., so it’s quite windy,” says Ted Rodormer of Net Zero Solutions, the distributor of American Wind products. He arrived at that figure using wind data at the three regional airports — Newark, La Guardia and JFK — plus the height of the co-op’s roof. “The turbines have no friction so they turn at lower wind speeds” — as low as 1.5 m.p.h. — “which gets rid of dangerous blades and noise and vibration, and also it doesn’t harm birds.”
Powering common areas. The array will include three backup batteries in the event of a blackout or a severe drop in wind speeds. The cost for hardware and installation will be between $650,000 and $900,000. With annual energy savings between $75,000 and $125,000, the co-op expects to recoup its investment in about five years. The co-op will also get a one-time federal investment tax credit, which rose from 26% to 40% of the installation cost after passage of the Inflation Reduction Act. The bulk of the project’s upfront cost will come from the co-op’s reserve fund, and a portion will be drawn from an earlier assessment that paid for repairs to the roofs and facades. The electricity generated by the wind turbines will help power the buildings’ common areas, and they’re expected to be up and running by the end of February 2023.
Meeting carbon caps. The potential of wind turbines is not confined to the suburbs. Schiller of Resolution Energy is working with numerous co-op and condo boards in New York City, where Local Law 97 of the Climate Mobilization Act will impose stiff fines on buildings that fail to meet prescribed carbon-emission caps, beginning in 2024. “For a lot of buildings,” Schiller says, “the WindWall offers tremendous value. For some buildings” — in sufficiently windy sections of the city — “it will be the only way for them to comply with the Climate Mobilization Act.”