September 6, 2023
The record has been broken for the longest distance of power delivery through a single fiber optics cable. Researchers with the Nippon Telegraph and Telephone Corporation (NTT) and the Hokkaido National University Organization Kitami Institute of Technology managed to deliver in excess of 1 W across a 10km distance, in addition to the high-speed data exchange allowed by fiber optics.
Previously, this had only been accomplished for a distance of up to two kilometers (due to optical intensity limits within the fiber itself). Thanks to this advancement, disaster relief & recovery and power delivery can be achieved in remote locations without the need for complex electrical infrastructure to be built (or rebuilt).
The research team’s feat made use of NTT’s multicore optical fiber (MCF), which is compatible with existing fiber optics infrastructure through its standard glass diameter of 125 μm. Each of these cores—individual optical strands within the standard glass—can be leveraged for their own purpose.
Using multiple cores for power transmission maximizes power delivery—and the research team did just that. The scientists pushed a light source with a wavelength of 1,550 nm into all four optical cores. For data transmission, two of the cores were injected with an additional wavelength around 1,310 nm, where both downlink and uplink data (with a transmission speed of 10 Gbps) could piggyback. With that, the researchers were able to send approximately 1 W of power across a 14 kilometer distance, achieving a world record: 14 W/km for their optical power supply system.