Hybrid fiber lighting systems (HFLS) using a cobination of sunlight and LEDs have bigger energy saving potentials than current conventional most efficient technologies for indoors use. Even when there is a big potential of CO2 reductions using HFLS the biggest barriers for their succeful mpleentation is their high price and a low quality of light. This project goal is to further develop a new concept of HFLS already suggested by RUC and DTU scientists. In cooperation with a interdisciplinary team the new system will be installed and tested in one school en the municipality of Stevns, DK.