City spins idea for wind rotors atop buildings
BY ALBERT AMATEAU | Are you ready for 55-foot-tall wind turbines atop buildings on the waterfront?
The Department of City Planning is contemplating a citywide “Zone Green” text amendment that would open more opportunities for wind turbines and other energy-saving measures.
Vivian Awner, a department spokesperson, made the pitch to the Community Board 2 Land Use and Business Development Committee on Feb. 9 for the amendment that would remove some impediments in the existing zoning text to “green” technology.
The energy-saving features on landmarked buildings or in historic districts would still be subject to Landmarks Preservation Commission review, and the technology would still be subject to Department of Buildings codes, Awner said.
Drawing an anxious response from local residents at the Feb. 9 hearing, the wind turbine amendment would allow the devices, including poles and rotors, to rise 55 feet above the rooftop of buildings that are more than 100 feet tall, provided the turbines are set back at least 10 feet from any property line.
On waterfront blocks, all buildings in medium- or higher-density residential, commercial or manufacturing districts could have rooftop turbines up to half the height of the building, or 55 feet, whichever is less. Free-standing wind turbines would be allowed in commercial and manufacturing areas on waterfront blocks. However, all wind installations would have to comply with Department of Buildings requirements.
The existing zoning text restricts wind turbines to the height limits of their districts, so buildings that are already at the district height limit currently cannot install wind turbines.
Assemblymember Deborah Glick told the committee that the proposal raises troubling questions.
“Are 55-foot-high wind turbines on buildings over 100 feet a good idea or a hazard?” Glick asked. “We don’t know of any existing wind turbines in the city, so we don’t have a lot of experience. But a 10-foot setback doesn’t seem like very much.”
Downtowners at the Feb. 9 hearing were also concerned about noise, as well as potential dangers, like ice flying off the rotors’ blades. Land Use Committee members noticed that there was no mention of the number of wind turbines to be allowed on a building.
The proposed text amendment also provides that the City Planning Commission chairperson could certify rooftop greenhouses to be exempt from existing floor-area and height limits on a building if these structures have no residences or sleeping quarters. The eligible greenhouse must not exceed 25 feet in height, must be set back from the roof edge by 6 feet and must include practical measures to limit water consumption. Glick wondered what impact rooftop greenhouses would have on birds.
The text amendment would also allow existing buildings to add up to 8 inches of external insulation while exempting the added space from floor-area calculations and regulations for yard and open space. New buildings whose walls are more efficient than required by the city code could have up to 8 inches of additional wall thickness exempted from floor-area calculations under the proposed amendment.
In addition, sun control devices and awnings above the ground floor would be allowed to project 2 feet, 6 inches out over required open areas.
While the current text does not allow solar panels above the maximum permitted building height, the amended text would allow solar panels on flat roofs anywhere below the parapet regardless of building height. Parts of solar installations higher than 4 feet would be subject to limits on roof coverage and height.
Green roofs, recreational decks, skylights and storm-water detention systems would be allowed anywhere below a building’s parapet regardless of building height. A guardrail up to 3.5 feet tall and no more than 30 percent opaque would be allowed above the top surface of a roof.
The text amendment is currently in a review process similar but not identical to the uniform land use review procedure (ULURP). City Planning referred the amendment to all of the city’s 51 community boards, borough boards and borough presidents on Dec. 12 for a 60-day combined review period, which concludes at the end of February.
The measure, with public comments, then goes to the City Planning Commission for a hearing and final draft. There is no time limit on the Planning Commission phase of the review, but the City Council has the final decision on the text amendment.