Wireless communication has to be redesigned to achieve sustainable communication infrastructure providing net-zero carbon dioxide emission. This paper presents a novel Light Fidelity (LiFi) design that exploits the concept of tubular light guides that can be installed in new buildings. While these guides bring natural sunlight indoors, our proposed system LiFiTube modulates it with low-power liquid crystal (LC) shutters to provide wireless data services without using any power hungry electronic components. Preliminary results show that our proposed LiFiTube system can provide a self-sustainable communication technology and can guarantee demands of Internet of Things networks, while illuminating indoors. We also draw some future research directions.