​Scientists design smart device to harvest daylight to relay to underground spaces

Singapore, 7 April 2021 – A team of Nanyang Technological University, Singapore (NTU Singapore) researchers has designed a smart device to harvest daylight and relay it to underground spaces, reducing the need to draw on traditional energy sources for lighting.

In Singapore, authorities are looking at the feasibility of digging deeper underground to create new space for infrastructure, storage and utilities. Demand for round-the-clock underground lighting is therefore expected to rise in the future.

To develop a daylight harvesting device that can sustainably meet this need, the NTU team drew inspiration from the magnifying glass, which can be used to focus sunlight on one point.

They used an off-the-shelf acrylic ball; a single plastic optical fibre—a type of cable that carries a beam of light from one end to another; and computer chip-assisted motors.

The device sits above ground and, just like the lens of a magnifying glass, the acrylic ball acts as the solar concentrator. This enables parallel rays of sunlight to form a sharp focus at its opposite side. The focused sunlight is then collected into one end of a fibre cable and transported to the other end that is deployed underground. Light is then emitted via this cable end.

At the same time, small motors—assisted by computer chips—automatically adjust the position of the fibre’s collecting end. This optimises the amount of sunlight that can be received and transported as the sun moves across the sky.

– Construction+ Online

Source: NTU Singapore