Study: Energy Efficiency of Computers Doubling Every 18 Months


Photo by bfishadow/CC

Those of us fighting the battle with computer batteries will appreciate this. Batteries have come a long way since the 1990s. For instance, if a MacBook Air were as efficient today as a 1991 computer, the battery would last for 2.5 seconds. In other words, it would be dead by the time you got to the end of this sentence. The Atlantic has the story. And it's bound to fan the flames of the PC v. Mac wars.
Flames also would refer to how quickly some PC batteries seem to burn out, compared to their Mac counterparts. I know, PCs are getting better. Don't get me wrong. But Macs have lead the battery longevity pack for some time.

The Atlantic story explains that kids going to college today have seen computers shrink from bulky machines into sleek gadgets (like the iPhone ... and the Windows Phone, in fairness).

And some of us out there will remember when college students didn't all carry cell phones at all. The increased efficiency of personal computers can be demonstrated in this little Atlantic example:

"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."

Take that to the bank. The trend has been pointed out by Jonathan Koomey, a Stanford consulting professor who's been studying the history of computing. According to a paper by Koomey, published in the July-September IEEE Annals of the History of Computing, "the electrical efficiency of computation has doubled roughly every year and a half."

He adds in an abstract on "Implications of Historical Trends in the Electrical Efficiency of Computing" that "These efficiency improvements enabled the creation of laptops, smart phones, wireless sensors, and other mobile computing devices, with many more such innovations yet to come."

MIT's Technology Review has more on the Koomey paper, calling his findings "A New and Improved Moore's Law." The study was conducted in collaboration with Intel and Microsoft, for the record.

Do you remember your first computer? How long your first laptop battery lasted?

Let's reminisce. Mine was an Amstrad that didn't even have a hard drive (Oldcomputers.com notes that the Amstrad's 57-watt power supply was integrated into its monitor. And the whole system is slightly larger than the MacBook Air).

My first laptop? It wasn't until decades later, with a Dell XPS, which won't hold a charge anymore, even with that newer replacement battery I bought.

Note to developers: Some of us wouldn't mind a new cell phone or laptop with a few less thousand needless features and longer battery life.

More on Computer and Batteries
I'm a PC, and I'm Greener Than a Mac
How Long Will Tomorrow's Automotive Lithium Batteries Last?
How to Go Green: Gadgets
Feed Your PC Granola (the Software) to Cut Energy Use

Tags: Electricity | Energy | Energy Efficiency

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