[mythtv-users] Proposed future power saving networked configuration (0.22 in mind)

[Michael T. Dean]

On 02/18/2009 10:40 AM, Jon Bishop wrote:
> On Feb 18, 2009, at 4:58 AM, Chris Pinkham wrote:
>> Sure, it will take me years to save enough power to pay for my
>> programming time to add this feature, but if it's $5-10 less that I'm
>> paying the power company each month it's worth it now.
> But it's worth it... them greedy utilities!  ... Well, actually, I
> believe that as a people, globally, we need to stop depending so much
> on utilities and corporate conglomerates and produce more of our own
> energy. Electricity is so easy to make, and there's so many ways to
> make it... it's just a shame that the inverters to take it from
> batteries and make it a nice pretty 60hz (or 50hz) sine wave are so
> darn expensive.

Actually, taking it to a nice pretty sine wave would be a travesty. 
Computers run on DC power, so if you attach your solar/wind/home-nuclear
generator to batteries, then attach an inverter to the batteries to make
AC, then feed that AC to the computer PSU, it will take the AC and turn
it back into DC...  So, you incur an efficiency loss going from DC->AC,
then compound the loss with a second efficiency loss going from AC->DC.

Just hook the batteries up to a DC->DC power supply unit, such as:
http://www.opussolutions.net/catalog/product_info.php?products_id=48
http://www.soltronixstore.com/Detail.bok?no=9
or, for those tiny systems,
http://www.mini-box.com/s.nl/it.A/id.417/.f?sc=8&category=13 or any of
the many others (there are actually tons more at those three sites, as
well as a bunch at other sites).

Then, once you get a working setup, write up a page on the wiki/your
blog/some forum and post a link here so I can do the same with some nice
Concorde Lifeline batteries ( http://www.batteryweb.com/lifeline.cfm ). 
It's charging the batteries that has me stumped, so far.

(I'm fully expecting you'll actually do this as I just shelled out for 4
more 80 PLUS PSU's to decrease my power usage, so you'll figure out how
to do the project I wanted to do instead now that I've already invested
a bunch in AC->DC PSU's.  See
http://www.gossamer-threads.com/lists/mythtv/users/371460#371460 to see
how the new PSU's are saving me $1.5/mo each at $0.10/kWh.)

Mike