Future Earth

Shadow energy

Leveraging shadows to generate energy


Darkness could become a source of renewable energy

New developments in photovoltaic panels have led researchers to develop an evolution in photovoltaic cells to utilise both light and shadow, a reality of the application in the real world where light is usually more discontinuous.

A similar approach to energy generation looks towards harnessing ambient indoor light into energy via the development of organic solar cells by a joint Chinese and Swedish researchers.

So, how does the shadow effect work?

A series of SEG (shadow effect energy generator) cells are aligned on a transparent membrane in two layers – a thin gold film and a silicon substrate. When the entire surface is exposed to light or shaded light, a very weak current is generated. However, when these same cells are partially illuminated, a significant electrical current is produced. This turns the cells into both a generator of energy, and a collector. The conditions of lighting in the average house generates a 1.2V current – the sort of power used to generate a digital watch.

With general movement, power is generated. Ideal in the applications such as wearable tech and smart clothing. Further developments could incorporate this technology on a larger scale, enabling photovoltaic panels in the home.

With lower costs than that of a conventional silicon cell, this is a positive step towards harnessing the world we live in towards using more sustainable and intelligent technology.

It seems clear that there are many opportunities to leverage the world around us to collectively change the approach we have to energy generation. With many researchers shifting the power paradigm, it’s about time we move away from traditional harmful methods to something new.