
Tracking two years of laptop battery use, sampled every minute - davidbarker
http://www.ifweassume.com/2014/07/better-living-through-data.html
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thadk
This doesn't involve the quantified self component but:

CoconutBattery Online ([http://online.coconut-
flavour.com/](http://online.coconut-flavour.com/)) has massively aggregated
Coconut Battery data ("over 150,000" data points) from the last five or eight
years of Apple laptop models.

It helps give a sense of laptop cohort's battery longevity.

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tenfingers
The method he's using might influence the statistics negatively a bit too
much, as there's periodical data that needs to be flushed to disk, plus an
useless fork going on every minute.

This popped up on HN last year, uses a much cleaner implementation:

[http://www.thregr.org/~wavexx/hacks/bcmon/](http://www.thregr.org/~wavexx/hacks/bcmon/)

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thrownaway2424
"A fun thing to notice: my computer apparently wakes up a few times every
night... I wonder what it's dreaming about?"

The fix for this is disabling "Wake for network access" in the preferences.

~~~
chillacy
Though note that "fixing" this will remove your mac's ability to handle
network requests when asleep, which is a pretty cool feature that I wish the
phones/pads had (they sleep the network cards to save power)

[http://support.apple.com/kb/ht3774](http://support.apple.com/kb/ht3774)

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watchdogtimer
Maybe I'm just missing it, but one statistic I would like to see is how long
it takes your battery to fully recharge, and how that statistic has changed
over time.

~~~
superuser2
The definition of "full" decreases steadily over time, all the way to the
point where "full" is no power at all.

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JimmaDaRustla
Remember, two things degrade batteries - heat and load. The former more so
than the latter, but they both go hand in hand. The heat is not a data point
variable the author has I imagine, but he has a decent representation of state
with the graph.

The first MBA seems to have more moments of "drained" battery, represented by
the orange/red colours being more predominant on the left side of the graph.
This may signify more load being placed on the first MBA than the second MBA.

The second MBA seems to have had an unusual beginning to its life - lack of
daily data and perhaps being left in a discharged state rather than charged.
Might have some play on the initial degradation of the battery's capacity, but
probably not.

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jedunnigan
Would minute to minute logging effect the battery performance and thus make
this data not entirely objective?

~~~
verisimilitude
I would think that even if logging used a non-negligible amount of battery
power to take measurements the data are still valid because such a load was
applied consistently throughout the sample period. So, the measurements are
valid within the set (you can accurately compare one day to another) but
perhaps not transferable/generalizable (could not compare them to other
laptops with differing monitoring periods).

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K2h
note the temperature is an important consideration instead of just the number
of charge cycles. for the whole story on a battery the log should include
battery temp, even when the computer is asleep.

[https://www.apple.com/batteries/notebooks.html](https://www.apple.com/batteries/notebooks.html)

~~~
specialist
Is percent charged also a factor?

If I understand correctly, I've read that fully charging a hot battery will
degrade the capacity.

If true, I'd like smart recharging to target some optimal charge, say 95%
full. (I think one of the PC laptops did this.)

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AnonJ
"Too much media/computer use isn't good for your brain. I worry computers are
making people less creative in some ways, and too much time online is
certainly bad for your soul. You need sunlight, air, dirt." Such statements
abound but actually don't make much sense. It's just the progress our society
is making and we should be proud and happy of it because it absolutely
enhances our productivity. People just need to adapt to new things over time
and overcome their resistance. I bet when pen and paper became popular similar
statements were made of them! Which are of course quite nonsensical examined
by time.

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Chris911
If you want to run this can of experimentation on your own, you can easily get
these data points from the command line using iStats[1].

[1] [https://github.com/Chris911/iStats](https://github.com/Chris911/iStats)

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jervisfm
>This newer 2013 MacBook Air is holding up much better than the 2012 model,
and I'm consistently still getting 6-8 hours of life out of the battery at
least.

It may be just my usage patterns but I never seem to get more than 4 hours on
the 2013 Air. I mostly have a fair number of Chrome tabs along with a terminal
window open and that seems to be enough to drain the batter rather quickly.

~~~
rsynnott
Chrome for MacOS seems to be quite badly behaved; you should see better
results with Safari.

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coin
I'm confused, is he tracking computer usage, or % of battery drained? If the
laptop is plugged in then battery drain won't show up. Also power draw will be
different than duration of computer use, as some tasks are more CPU intensive.

~~~
micampe
He is tracking battery capacity (Current Capacity / Max Capacity), not battery
drain. This is useful to track the lifetime of the battery itself, instead of
its charge.

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stanzheng
What tool did the author use for tracking? this seems like an interesting
metric everyone should track.

edit: batlog a cronjob the author wrote

[https://github.com/jradavenport/batlog](https://github.com/jradavenport/batlog)

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anonfunction
"Measure what is measurable, and make measurable what is not so." \- Galileo

~~~
yread
Playing Civilization V?

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wodenokoto
How does this show if one battery is better than the other? Doesn't it just
show how often he charges his batteries?

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jelloPuddin
>>Too much media/computer use isn't good for your brain

I was really interested in the article until this popped up. What a gross
generalization.

~~~
heydenberk
This is obviously and objectively true for a sufficiently high level of
"media/computer use", and I think many of us will say, anecdotally, that we
have bumped up against this limit. What's so offensive about it?

~~~
sliverstorm
People in denial (in this case about the health of endless computer usage)
tend to react violently when you confront the issue.

