Energy-hogging Linux, what to do?

[richb at pioneer.ci.net (Rich Braun)]

Call it the Katrina effect:  news headlines about higher natural gas prices
coming to your NSTAR bill soon led me to wonder why my electric bills are *SO*
high even with all those compact-fluorescent bulbs installed everywhere.  I
dug out five years of bills, entered my meter readings into a spreadsheet, and
concluded that a 40% jump in household consumption in the fall of 2003
coincided with the addition of a handful of computer components.

Even at current prices, it looks like my Linux energy bill tops $500 per year,
out of the $2000 in electric bills.  (I will find out soon, have mail-ordered
a couple of Kill-a-Watt consumption meters to plug my systems and appliances
into.)  Lord knows what next year's bill will be, if natural gas prices remain
2x what they were pre-Katrina.

Want to find out how much your nice new Linux server will cost in annual
electricity consumption, before you buy it?  Sorry, you can't:  no
manufacturer anywhere posts energy consumption information.  In fact most of
'em try to get you to buy into the whole energy-bloat mantra of more watts
(isn't a 450W PSU more impressive than a 250W one?) or more gigahertz.

A little googling leads me down the path of the Via EPIA motherboard, the
Pentium M processor, and DC-to-DC converters that run on 12V instead of normal
120V PSU's.  Have yet to figure out how much energy those econobox UPS units
are eating up; power efficiency ratings on those are nowhere to be found.  And
so it goes:  we Americans happily plug all these things in without a thought
to anything other than the $10 we saved shopping around for the lowest
purchase price, ignoring the $200 we'll spend each year leaving the thing
plugged in 24/7.

So my next server overhaul will include low-power motherboards and DC-DC
converter products.  I'm posting here to inspire some discussion on the topic:
 we like to think we're energy-efficient here in so-called liberal
Massachusetts, but when I found out that my Linux boxes were burning my energy
than my *car*, I decided it's time to change something.

Have any of y'all built low-power or solar-powered Linux servers?

-rich