In the last two decades, technology has evolved at a rapid pace and everything that was thought impossible in the 80s and 90s is possible today and is already in the hands of consumers. Wanting to highlight the enormous progress made in making the energy consumption of our computers more efficient, those from The Atlantic compare today's MacBook Air with a computer from the 90s. They say that the MacBook Air with its 50W/hour battery would have had an autonomy of only 2.5 seconds in the 90s and all because then energy consumption was not as efficient.
Imagine you've got a shiny computer that is identical to a Macbook Air, except that it has the energy efficiency of a machine from 20 years ago. That computer would use so much power that you'd get a mere 2.5 seconds of battery life out of the Air's 50 watt-hour battery instead of the seven hours that the Air actually gets. That is to say, you'd need 10,000 Air batteries to run our hypothetical machine for seven hours. There's no way you'd fit a beast like that into a slim mailing envelope.
It seems that from the 90s until now, the energy consumption of our computers has become 2 times more efficient every year and a half and today we can get 7 hours of autonomy from a MacBook Air and over 5 hours from a MacBook Pro. Probably in 20 years we will be able to get 0 days or half a day of autonomy from our laptops, but everything depends on how energy consumption will be made more efficient.
