Air Battery Would Last 2.5s on Machine with 1990's Efficiency

Air Battery Would Last 2.5s on Machine with 1990's Efficiency(theatlantic.com)

92 points by allanca 14 years ago | 44 comments

Bud 14 years ago |

Um, I doubt this, very very much.

The Air has a 50 W/h battery. That's 50W for a full hour. So if they are saying that it would last 2.5 seconds, that means the putative 1990s computer would have to consume 60 x 24 x 50 = 72,000 Watts!

Someone at the Atlantic needs to figure out basic math.

roc 14 years ago | |

I read it to mean they were factoring in the computing power as well.

i.e. they estimated that it would take 72,000 Watts-worth of 1990s computers to match the processing power of a Macbook Air.

Though that does add further caveats to an already less-than-ideal comparison (as an MBA is not going to last seven hours at 100% CPU load).

davidw 14 years ago | | |

Sounds like they ought to mention how long that is in football fields.

hmottestad 14 years ago | | |

Yes, it must be. And from 1990 to 2011 number of transistors per cm2 has doubled 14 or so times.

If they are going to compare it with computational power, they should also factor in battery development since 1990.

mortenjorck 14 years ago | | |

What is missing is how many 603ev chips would be needed to approximate the Sandy Bridge Core i5's performance. And of course, how many feet thick that would make the 2.5-second-battery 1997 MacBook Air.

rauljara 14 years ago | |

Did you read the article? "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."

It would take an awful lot of 1990's machines to equal the computing power of a macbook air.

pjscott 14 years ago | |

I'm being pedantic here -- units are Serious Business -- but "W/h" is "Watts per hour". You want "Watt hours", which you could write "W-h".

eru 14 years ago | | |

Or as Wh. Like we write Nm for Newtonmeter.

pascal_cuoq 14 years ago | |

If you read the article, it's clear they mean an hypothetical 1990s computer with the computing power of the modern macbook air, and the power efficiency typical of computers of that era.

Completely nonsensical, I'll grant you.

nickpp 14 years ago | |

I would guess that "computer that is identical to a Macbook Air" is key here: it means the current Air's power. That would probably be a mainframe in those days?

hvs 14 years ago | | |

I'm not sure that such a thing existed.

Symmetry 14 years ago | |

I think rather that a 1990s computer would take the full battery (or 180 kJ) to accomplish the same tasks that the macbook air could in 2.5 seconds of operation (~50 J?). So if you changed the task efficiency of the Macbook air to be that of an old computer, but kept the same processing power, the Macbook Air would be consuming 72,000 Watts.

rayiner 14 years ago | |

I think that's the reason for the distinction between "a 1990 computer" and a "computer with 1990 energy efficiency." It's explained quite clearly in the article itself.

bryanlarsen 14 years ago |

A counterpoint: the Air still does not match the battery life of a TRS-80 Model 100 from 1983: 20 hours on 4 AA batteries.

A Model 100 was pretty much the opposite of the iPad: great for creative activities (writing, taking notes, programming) but poor for consumption activities.

DannoHung 14 years ago | |

If you strictly limit the creative activities there are to ones that involve typing. I'll bet the iPad is way better at making music, drawing, photo and film editing, etc, etc.

ugh 14 years ago | |

Writing is important – but not everything.

flamingbuffalo 14 years ago | | |

exactly. I've posted this before, but: "if a person can't produce something on an ipad that's a reflection of the user, not the device."

marbletiles 14 years ago |

so if someone could make a 68030 as efficient as an i5, I could have a PowerBook 170 that would run for a week on a charge? Yes, please.

( I'll need someone to knock up a Twitter reading client in MPW too, pls)

phil 14 years ago | |

Heck, why not go even further back?

http://atomsandelectrons.com/blog/2010/04/apple-t/

zokier 14 years ago | |

Modern MCUs are relatively power efficient, and certainly are available in 68030s performance region. But their architecture might not be very suitable for general purpose computing.

modeless 14 years ago |

This is just another way of stating Moore's law. Chip transistor count doubles every year and a half; chip power use doesn't.

skeletonjelly 14 years ago |

Oh Macbook Air. For some reason my tired brain kept thinking about what an Air Battery would look like.

ghshephard 14 years ago | |

Something like this: http://www.youtube.com/watch?v=f2a3uTU0fgc

skeletonjelly 14 years ago | | |

Wow. It exists! Thanks.

rnernento 14 years ago |

Makes sense to me. If they calculated that in 1990 it took x watts to generate y processing power by now x has gone wayyyy down if y remains the same. They don't have the best documentation but it doesn't seem unreasonable.

keeperofdakeys 14 years ago |

Here is an older, portable Macintosh with more (claimed) battery life than most of the modern Macs.

http://www.youtube.com/watch?v=gGwVTq_xcZk

ck2 14 years ago |

If only battery technology had kept up with computing technology.

We'd definitely all be driving electric cars today if that happened.

The best (commercial) batteries today are only a few times better than the ones used in electric cars 100 years ago.

eru 14 years ago | |

I've read the rate of improvement for batteries is around 8% a year. That's still exponential, just not as good as transistor count. But nothing else improves that fast.