Abstract-The new field of green communications can be divided into a) energy-efficient communications equipment or b) using information and communication technology to improve the world to become more energy aware. Mobile data traffic and utility energy consumption have a lot in common. There is a limited supply due to limited resources, and only growth (of quantities, technology) can increase this, at the cost of a higher carbon footprint. The green index is defined here for cellular wireless.On the other hand there is a demand which is user-generated, variable over time and space, and ever increasing at a fast pace. Flat rates or almost flat utility tariffs have spoiled users and established high user expectations. Instead of engineering for the growth of supply, this paper investigates how to engineer for controlling the demand side. Dealing with congestion is a consequence of the supply=demand regime and the end of overprovisioning. New tariffs are required that are tailored to the major QoS classes and help to shape demand at the user and application level. This paper investigates QoS-aware demand shaping and control by user-in-the-loop and tariff-based control.