It might sound like a sci-fi story, but the most recent Shadow-Effect Energy Generator (SEG) is an accurate prototype device.
The intriguing concept could help scientists to remodel the way renewable energy is produced indoors. Here is what you should know.
Electricity From Shadows – More Than An Idea
The Shadow-Effect Energy Generator utilizes the contrast between darkness and light to generate electricity. It’s made from a set of thin layers of gold film on a silicon wafer, on top of a flexible plastic base.
Whereas shadows usually are an issue for renewable solar energy production, now they’re bound to keep on producing power. Such a technology – cheaper to develop than a typical solar cell – generates small amounts of power and could be utilized in smartphones.
“In this work, we capitalized on the illumination contrast caused by shadows as an indirect source of power; this novel concept of harvesting energy in the presence of shadows is unprecedented,” explained Tan Swee Ching, a scientist from the National University of Singapore.
The difference between shadow and light is what makes the SEG device useful. Under changing shadows, for instance, the SEG is twice as efficient as standard solar cells under the same conditions. So, when the SEG is entirely in shadow, or solely in the light, it generates a low amount of electricity or nothing.
With shifting shadows – triggered by clouds or moving tree branches perhaps, or the movement of the Sun – the device can produce enough power (1.2V) to operate a digital watch, the team found. Such a thing could well be increased in the future. The SEF also doubles up as a sensor; it logs shadows moving over it to record the flow of objects passing by.
Shadows can be put now on the list of alternative energy sources, alongside the cold of outer space or snowfall. The more ways we have of generating renewable electricity, the more creative we can become with our gadgets, and we wouldn’t have to rely so much on fossil fuel.