Rapid advancement in ICT is promoting us into an era of unprecedented prosperity & countless possibilities. However, there is one gloomy side of the ICT technology that contributes toward the inflation of carbon footprint. Research from 2020, estimates the ICT sector, carbon emission, to be 1,100 million tons. The future generation networks and IoT will further escalate this figure, as these would overburden the core ICT pillars i.e. Data Centers (DC's), and Mobile networks (NT). This in turn will inflate the ICT power consumption and leads to more carbon emission. Thus researchers and industries are continuously putting efforts to transform ICT into Green ICT. Apart from this, there is one bright side of ICT i.e. “Green BY ICT” that helps other industries to abate their carbon emission using smart IoT applications. However, the smart IoT devices/sensors/actuators used for this are mostly battery-operated. To reduce the battery waste, efforts are also being made to either prolong their battery life or to make them self-powered or battery-free. This survey discusses both aspects of ICT i.e. Green of ICT and Green by ICT. Firstly, the recent approaches for the Greening of ICT include techniques for Green-DC, Green-NT are discussed. Post discussing this, the paper also confers the energy harvesting solutions & energy-efficient techniques for the greening of user device/senor. In continuation of this, 5G green physical layer solution, Narrowband Internet of Things (NB-IoT) that prolongs battery life is also discussed, including its enhancement from release 13 to release 16, recent techniques to further optimize the NB-IoT performance, and future research challenges. Apart from this the recent advancement related to renewable energy solutions for Green ICT is also discussed. Overall this survey concludes that ICT's own environmental impact must be evaded, to utilize the ICT's tremendous potential.

信息通信技术的飞速发展正在推动我们进入一个前所未有的繁荣和无数可能性的时代。然而，ICT 技术有一个令人沮丧的一面导致碳足迹膨胀。2020 年的研究估计，ICT 部门的碳排放量为 11 亿吨。下一代网络和物联网将进一步提升这一数字，因为这些将使核心 ICT 支柱，即数据中心 (DC) 和移动网络 (NT) 负担过重。这反过来又会增加 ICT 的功耗并导致更多的碳排放。因此，研究人员和行业正在不断努力将 ICT 转变为绿色 ICT。除此之外，ICT还有一个光明的一面，即“Green BY ICT”，它可以通过智能物联网应用帮助其他行业减少碳排放。然而，用于此的智能物联网设备/传感器/执行器大多是电池供电的。为了减少电池浪费，还努力延长电池寿命或使它们自供电或无电池。本次调查讨论了 ICT 的两个方面，即绿色的 ICT 和绿色的 ICT。首先，讨论了最近的 ICT 绿色化方法，包括 Green-DC、Green-NT 技术。在讨论此问题后，本文还介绍了用于用户设备/传感器绿化的能量收集解决方案和节能技术。继续讨论5G绿色物理层解决方案，延长电池寿命的窄带物联网（NB-IoT），包括其从版本13到版本16的增强，进一步优化NB-IoT性能的最新技术，以及未来的研究挑战。除此之外，还讨论了与绿色 ICT 可再生能源解决方案相关的最新进展。总的来说，这项调查得出的结论是，必须避免 ICT 自身对环境的影响，以利用 ICT 的巨大潜力。