Green Power in the City

Mayor Michael Bloomberg has proposed a bold green-power vision for New York. As a first step his administration has issued a formal request for proposals to exploit natural energy sources (wind, solar and water) to power the city.

Giromill Vertical-Axis Wind TurbineGiromill (Eggbeater) Vertical-Axis Wind TurbineLicensed under the GNU Free Documentation License by Stahlkocher

Wind Turbines

Bloomberg anticipates proposals for installing solar panels and wind turbines on high-rise roof tops and bridges. Giromill or "Eggbeater" wind turbines (a type of vertical-axis wind turbine) have the potential to be integrated in to a building's structure. While vertical-axis wind turbines are less sensitive to wind direction they suffer from lower efficiency than horizontal-axis wind turbines.

A likely roof-mountable wind turbine is the so called micro (or personal) wind turbine. However, such small wind turbines need to be mounted with unobstructed and consistent access to the wind - not always possible in high-density housing areas typical of cities. Also, small wind turbines don't tend to yield much power when compared to the power demands of the average household, so there's a strong motivation to propose a total solution that also embraces energy conservation.

Wind Farms

Bloomberg also mentioned that offshore wind farms have the potential to supply up to 10% of New York's energy needs.

Wind TurbineOffshore Horizontal-Axis Wind TurbineLicense: CC BY 2.0, phault

At this point in the green-power revolution, offshore horizontal-axis wind farms are the most efficient and reliable means to produce power from the wind. The only constraint is the "not in my backyard" policy employed by some who are not willing to sacrifice a little for the greater good. Case in point is the strong opposition to the Cape Wind wind farm proposal on Horseshoe Shoal in Nantucket Sound (off Cape Cod, Massachusetts) from a small number of influential (wealthy) local residents.

Tidal Turbine

New York is already pioneering the use of a prototype tidal turbine to generate power from the East River. The river's strong tidal current drives a horizontal-axis water turbine (think wind turbine but smaller).

The power extracted from tidal water movement is more reliable (6 hours upstream and then 6 hours downstream, as long as the Moon keeps orbiting the Earth) than the less predictable wind that drives wind turbines.


It's worth remembering that Bloomberg is asking for proposals, so this is analogous to the concept design phase during product development. It's a time to cast the net wide and see what your fertile imagination can come up with - a great moment for lateral thinking. Don't forget, if you need virtual engineering tools to analyze your proposal, our Caedium Professional add-on is ready and waiting.