2)A complete desktop uses an average of 200 Watt hours (Wh). This is the sum of the average consumption per hour of the computer itself (171 W), the internet modem (10 W), the printer (5 W) and the loudspeakers (20 W). Assuming that a computer is on for eight hours a day, the annual consumption comes to 600 kWh. That corresponds to CO2 emissions of about 175 kg per year, i.e. 1.75 % of the average annual emission of a Belgian.