Scientists have created a device that generates energy thanks to the shadow

The SEG generator works most efficiently when half of its surface is illuminated by bright sun, and the other half is in the shade.

In solar power generation, shade is a problem that hinders efficient generation. However, scientists from the National University of Singapore have managed to use this problem for good. The Shadow-Effect Energy Generator (SEG) they developed is described in an article published in Energy & Environmental Science.

The operation of the SEG generator is based on the potential difference between the parts of the device that are in the light and in the shade, respectively. Due to this difference, an electric current is generated. The generating surface itself consists of cells in which an ultrathin gold film is deposited on a silicon wafer.

Despite the use of gold in the design, the developers claim that the SEG generator will be noticeably cheaper than “classic” solar panels. In addition, the first tests of the device showed that in conditions of variable illumination it is twice as effective. “We also found that the optimal surface area for power generation is when half of the SEG element is lit and the other half is in shadow, as this gives enough space to generate and collect charge, respectively,” says Andrew Vee, one of the developers of the device.

The prototype, created by the team of scientists, gave a current of 1.2 V. This was enough to keep the digital clock running. This is not too much, but the authors of the project promise to increase its capacity. Interestingly, the SEG-generator can also act as a motion sensor: it is able to respond to the movements of objects that cast a shadow on the device.

“Due to its cost-effectiveness, simplicity and stability, SEG offers a promising architecture for generating clean energy <…>, and can also be used as part of smart sensor systems, especially in buildings,” the authors of the work write. However, the SEG-generator still has a lot of improvements. First of all, developers want to find a cheaper alternative to gold film, as well as adapt the technology for portable wearable devices.