Alternative power/recharging source?

John Gilmore gnu at toad.com
Sat Feb 23 05:37:25 EST 2008


There has long been a lot of confusion about power consumption.  Many
statements were made over the years about the *design goal* for power
consumption.  The XO did not actually hit that design goal -- but
since suspend/resume was the last major feature to debug in the
hardware, until it got to the mass production stage, it was hard to
measure its final power consumption.

For example, OLPC put out a press release on October 22, 2007,
entitled "OLPC XO is world's 'greenest' laptop computer", claiming
that "When idle, the XO laptop uses a single watt of electricity."

  http://wiki.laptop.org/go/Image:Green.doc

Then it went on to suggest how many gazillion barrels of oil would be
saved if every computer did this.  Only problem is, it's claiming the
design spec, not a measured value.  I haven't seen the raw
measurements on MP hardware, only the ones reported to the weekend
olpc community news.  But Chris Ball measured it two weeks ago, and a
mass production XO in sleep was burning 2064 mW (2 Watts +).

Another place that needs updating:
http://wiki.laptop.org/go/Classmate_and_XO_Laptop .  It says Typical
Laptop Power Draw is 0.5W mesh mode; (1W ebook Mode (idle)); 2-4W
typical; 4-6W power user (max).

There are probably more low-power references in slide decks shown at
various conferences.

I'm sure that there are things that still can be done in software
(and/or rolling in hardware improvements on the production line) to
reduce this power draw without losing any functionality.  It was
*designed* to use only a watt in suspend, and only two watts averaged
over a week.  But it's not at 1W yet, and may never get there.

	John



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