By Sarah Trefethen

It’s something you might see in the television skyline of a future city: flying cars, window-cleaning robots, and gently spinning, power-generating pinwheels rising from the roofs.
A future of wind turbine-topped buildings got a boost recently when the New York City Department of City Planning included a provision for wind towers of up to 55 feet in height in its proposed “Zone Green” amendment to the city’s zoning code, currently under public review.
But, experts say, the limitation of wind-power technology means the zoning change, if approved, is unlikely to drastically alter the appearance of the city any time soon.
“We can design something that can be very spectacular with a turbine, but there are a lot of practical limitations,” said Jason Kim, a senior associate at Kevin Kennon Architects who has worked on a number of LEED-certified projects.
In cases where wind turbines have been installed in the city to date, they have been relatively small and may contribute more to the marketing and image of a building than its power consumption.
A facility that generated enough power to make economic sense would put considerable structural strain on the building beneath, according to Anthony Pereira, president and CEO of altPOWER, a Manhattan-based firm that specializes in the design of sustainable energy systems.

“The nature of turbines is that they move,” he said. “Unless the structure is made for them, they’re probably not going to be a good alternative.”
And new construction couldn’t be put just anywhere, he said. “Assuming that the structural engineers have designed the building in a way that allows for the attachment of these things, it needs to be somewhere with the right wind.”
Of the zoning amendment’s numerous provisions — which include allowing for rooftop greenhouses as well and thicker, better-insulated walls — the wind turbines generated the most controversy when the proposal made the rounds of the city’s community boards, drawing the ire of preservationists and residents concerned that any rooftop wind turbine would be an inevitable eyesore.
But not all designers agree.
“I think it’s an interesting opportunity for architects to incorporate this kind of kinetics into their design,” said Craig Graber, an associate at Perkins + Will.
Turbines don’t have to have pinwheel-like blades, he pointed out. Some models look more like a double helix.
A simple internet search reveals a number of renderings of innovative designs for incorporating wind power into buildings, including a tower surrounded by vertical rotating blades from the Australian artist Michael Jantzen.
But Scott Yocom, a senior associate architect also with Perkins + Will, was sympathetic to community concerns that commercially viable, 55-foot tall wind plants would be visually obtrusive.
“My thought is, let’s not think of wind for New York City, let’s think of solar,” he said. “We can count on it, and as long as you’ve got the sun, you’ve got the power.”
The city’s proposal also allows for greater opportunities for rooftop solar panels, and Pereira also pointed to solar as a much more practical energy alternative for the majority of New York building.
In spite of his skepticism that the Manhattan skyline will ever resemble a wind-power forest, however, Pereira praised the planning department for taking a lead among America cities in providing for the technology.
“Somebody will do it,” he said. “This is a big city. Somebody will have the right location and the stars will line up and it will happen.”
The City Planning Commission is expected to vote on the Zone Green Text Amendment today (Wednesday.) Following the Commission’s vote, the City Council will have 50 days to review the proposal.