Sustainable energy technology has always been about finding new power sources that are clean and plentiful. Scientists from the University of Massachusetts at Amherst claim to have developed a device that can generate power from what may be the cleanest and most plentiful source imaginable: thin air.

Writing in the journal Advanced Materials, the scientists describe a device they created that makes power much like a cloud generates lighting. The cloud and the device generate electricity from the buildup of electrical charges in water particles.

The device, or harvester, operates on what the scientists call the "air-gen effect,” which is the ability to generate electricity from the humidity in thin air. It is a nano device, meaning that it is incredibly small, and it is filled with holes or "nanopores,” each smaller than 100 nanometers. When molecules from water vapor pass through the holes, they back up and this creates an imbalance in charges, or voltage, that can be captured in the form of an electrical current.

The scientists tout the many possibilities of this nano device. It can be constructed of virtually any type of material, so long as it is outfitted with the requisite nanopores. Different devices could be constructed of varying materials to suit different needs and environments.

Because it is so small, about the width of a human hair, it can be stacked and placed almost anywhere. The device could be used for small or micro power generation, like for individual devices, or it can be stacked for larger power generation.

Finally, because it relies on moisture in thin air, which is available all the time, it can also generate power throughout the day. This is a great advantage of intermittent sources, like solar and wind, which can only generate power when the sun is shining or the wind is blowing. In effect, the device can act like a battery that is always on.