You're right, it's about electricity consumption. However, the Nature article is from 2018, much has changed since. Also, 2% is a rather low estimate. There's

You're right, it's about electricity consumption. However, the Nature article is from 2018, much has changed since. Also, 2% is a rather low estimate. There's very different data, as well, e.g., from a SIA/SRC report: > For this benchmark energy per bit, computing will not be sustainable by 2040, when the energy required for computing will exceed the estimated world’s energy production. Thus, radical improvement in the energy efficiency of computing is needed. https://www.semiconductors.org/wp-content/uploads/2018/06/RITR-WEB-version-FINAL.pdf https://www.semiconductors.org/wp-content/uploads/2018/06/RI... One way to tackle this is reducing the number of bits moved.