Smartphone apps collect more user data (also called tracking) than most consumers would like. Besides privacy risks, the unsolicited collection of this data also has a carbon footprint. In this study for the European Green party, CE Delft investigated the amount of CO2 emissions related to this unwanted data transfer.
In this study we defined the unwanted data use by smartphone apps as the network data (both cellular and Wi-Fi) used to transfer the data collected by third-party advertisement and tracking services (ATS) in smartphone apps to the third-party servers. As approximately 60% of consumers indicate they would turn off third-party tracking, 60% of the network data used by ATS was qualified as unwanted.
To determine the carbon footprint of unwanted data-use, we combined the information on the amount of network data used with the electricity consumption of the data network and the carbon footprint of electricity production.
This analysis results in an estimated total carbon footprint of ATS data-use in Europe of between 5 and 14 Mt CO2-eq. per year, implying a carbon footprint of 3 to 8 Mt CO2-eq. per year for unwanted data use for ATS . This is comparable to the CO2 emissions of 0.7 to 1.8 1,000 MW coal-fired power plants, the CO2 emissions of European cities like Turin or Lisbon, or the CO2 emissions of 370 to 950 thousand European citizens.
To compensate 3 to 8 Mt CO2 emissions, 160 to 410 million trees would need to grow for one year, or 60 to 150 million PV panels would have to be installed to replace the average European electricity production.