ICT energy consumption is a growing concern. With an expected exponential growth in data transport, the communications infrastructure alone may soon become one of the largest energy consumers in the world. This trend has long been detected and is addressed at various levels. The first to respond were the equipment manufactures, and modern equipment is considerably more energy efficient than the one deployed a decade ago. Given the growth rates in mobile data traffic, better equipment alone will not suffice to successfully fight exploding energy demand. Its smarter use, exploiting inherent, yet not fully explored intelligence in the networks shall further improve energy efficiency.The objective of the GreenNets proposal is to tackle this challenge for cellular radio networks. This is to be done by developing sophisticated methods and tools in four directions: for analyzing the energy efficiency in existing deployments; for finding measures to improve the efficiency; for implementing those measures in dedicated software platforms; and for establishing the ability to migrate to more energy efficient radio network deployments in face of sharply rising mobile network traffic. The ambitious aims of the project call for R&D activities that will extend and complement the platforms, tools and methodologies already in the possession of the participating SMEs. In a nutshell, the research aims at establishing two complementing functionalities: First, an automated network management that continuously adapts network activity to match the spatial and temporal network traffic variations. This shall leverage better efficiency in the short-to-mid term. Second, the ability to optimize the evolution of network deployments such that they become even more energy efficient in the mid-to-long term. Both lines are compelling extensions of the businesses the three GreenNets SMEs make today.