Renewable energy for low carbon emission IP over WDM networks

In this paper we propose a low-carbon emission IP over WDM network where renewable energy is used to replace some of the non-renewable energy sources. We develop a Linear Programming (LP) model with the objective of minimizing the non-renewable energy consumption and propose a novel heuristic for improving renewable energy utilization. Compared with routing in the electronic layer, the results show that routing in the optical layer coupled with renewable energy at nodes significantly reduces the CO₂ emission of the IP over WDM network considered by 49% to 71%, and the new heuristic introduced hardly affects the QoS. Another LP model is developed to identify the optimum location of nodes that employ renewable energy. The results show that the nodes at the centre of the network have more impact than other nodes if they use renewable energy sources.