Windmills have dotted the Dutch countryside for centuries. But in densely populated cities, whooshing turbines are a tough sell. A new concept called the Dutch Windwheel could offer a silent, low-maintenance alternative.

Whereas most turbines use spinning blades to turn the kinetic energy of wind into mechanical energy that generates power, the Windwheel cuts out the middle step. Its electrostatic wind-energy converter uses wind, water, and an electric field to directly produce a current.

So far, the tabletop prototype produces just 12.5 milliwatts—not enough to power a light bulb. And it's only 3 percent efficient, compared with a typical wind turbine's 45 percent efficiency. But if the technology advances on schedule, its creators say a 570-foot version could grace the Rotterdam skyline by the early 2020s.