Energy consumption of telecommunication access networks

VDSL2-Vectoring HFC FTTH – PtP FTTH – GPON Total energy consumption [MWh/year] 3,465 4,987 3,557 3,156 kWh/year per person 61 88 63 56 Compared to 4-person household [4,200 kWh/year] 6% 8% 6% 5% CO 2 Emission [tons/year] 1,850 2,663 1,899 1,685 Figure 31: Annual energy consumption and CO 2 emission. The annual energy consumption can be derived from the determined power consumption, see Figure 31. If the energy consumption is normalised to the population of the model region, the per capita demand is between 56 kWh und 88 kWh per year. An average German 4-person household has an annual energy consumption of 4,200 kWh, according to the Federal Statistical Office. The energy consumption to operate one of these access networks is equal to 5% to 8% of the energy consumption of a 4-person household. The CO 2 emissions are between 1,685 and 2,663 tons per year. Based on these figures, the FTTH – GPON network has the most efficient access network. The customer premises equipment of the VDSL2 Vectoring network is the most energy efficient. However, the energy efficiency of the customer premises equipment of the FTTH networks can be improved significantly. So far, the access technologies were compared under the premise of a minimum data rate of 50 Mbit/s per subscriber. This does not take the individual performance and development capabilities of the different technologies into account. Normalising the energy consumption to the maximum transmission volume per year can show the capabilities and the energetic performance of the different access technologies. As shown in Figure 32, VDSL2 Vectoring, HFC and FTTH – GPON provide asymmetrical data rates for the upstream and downstream (currently offered data rates in Germany). It can also be seen that the usable data rates of VDSL2 Vectoring and HFC are significantly smaller than the data rates of FTTH technologies. That leads to a much bigger annual transmission volume of the FTTH technologies. By normalising the respective subscriber’s annual transmission volume to the specific energy consumption of each access technology, the energetic performance (annual traffic volume per 1 kWh) becomes clear. As can be seen in Figure 32 the energetic performance of the FTTH technologies is by far higher than of the other two. It is with 56 Tbyte/kWh and 47 Tbyte/kWh over 10 times as high as for VDSL2-Vectoring. 29