Sustainability has become an important aspect of all human activities, and also for accelerator driven research infrastructures. For new facilities it is mandatory to optimize power consumption and overall sustainability. This presentation will give an overview of the power efficiency of accelerator concepts and relevant technologies. Conceptual aspects will be discussed for proton driver accelerators, light sources and particle colliders. Several accelerator technologies are particularly relevant for power efficiency. These are utilized across the various facility concepts and include superconducting RF and cryogenic systems, RF sources, energy efficient magnets, conventional cooling and heat recovery. Power efficiency has been a topic in the European programs EUCARD-2, ARIES and the ongoing I.FAST project and the documentation of these programs is a related source of information. Proceedings of the 13th International Particle Accelerator Conference, IPAC2022, Bangkok, Thailand