The wireless data traffic grows by 50% per year which implies that the energy consumption in the network equipment is also growing steadily. This raises both environmental and economic concerns. In this episode, Erik G. Larsson and Emil Björnson discuss how the wireless infrastructure can be made more energy-efficient. The conversation covers the basic data traffic characteristics and definition of energy efficiency, as well as what can be done when designing future network infrastructure, planning deployments, and developing efficient algorithms. To learn more, they recommend the IEEE 5G and Beyond Technology Roadmap article “Energy Efficiency” (https://futurenetworks.ieee.org/roadmap) and also “Deploying Dense Networks for Maximal Energy Efficiency: Small Cells Meet Massive MIMO” (http://arxiv.org/pdf/1505.01181). Music: On the Verge by Joseph McDade. Visit Erik’s website https://liu.se/en/employee/erila39 and Emil’s website https://ebjornson.com/