[mythtv-users] [Slightly OT] solar power for all our gadgets

[Mark Knecht]

On Mon, Mar 9, 2009 at 11:00 AM, Michael T. Dean
<mtdean at thirdcontact.com> wrote:
> On 03/09/2009 01:14 PM, Mark Knecht wrote:
>>
>> I posted this once before but here's the current rates for my place in
>> Northern CA:
>>
>> Baseline up to 378 Kwh = $0.11536
>> 101%-130% (113.4 Kwh) = $0.13115
>> 131%-200% (264 Kwh) = $0.24711
>> 200%-300% (576 Kwh) = $0.35432
>>
>> There's a BIG jump over 200% baseline which is where I figure my
>> MythTV costs come in as we end up at about 150% baseline even on
>> vacation. My place with CFLs, pool equipment, electric range and lots
>> of MythTV equipment comes in at the range of 225%-250% of baseline for
>> about $200/month charges. Note that this is nearly 1000 Kwh! (937 on
>> the current bill...) Generation and distribution were about $160 of
>> the $200.
>
> I /highly/ recommend other options for saving money on power, too...  When
> it comes to Myth, a couple of easy things you can do are, a) make sure you
> get 80 PLUS certified power-supply units and b) (the /best/ solution) turn
> off your Myth boxes when not in use.

The Linux boxes in the house that run 24/7/365 right now is the master
backend and the Roku WatchInstantly machine. Every other PC is off
overnight and mostly off during the day. The dedicated Myth frontends
generally only run 1-2 hours/day and are small boxes anyway. (200W
PSU?)

Note that a machine that's shut down isn't necessarily no power. We've
placed switchable power strips and arranged connections so that when
nothing is in use we cut power to everything. Around the TV this means
the STB and Roku have power 24/7 but the TV, receiver, mythfrontend,
DVD player do not. Every room in the house is this way.

A slave backend is just more power.  I built one but I couldn't get it
to communicate with the master backend properly so I shut it off 6
weeks ago in frustration.

>
> As for the 80 PLUS PSU's, they're saving me about $1.50/mo per backend with
> rates of:

What's the up-front cost of replacing PSUs? I somehow doubt I'd get my
money back in a year, even at my inflated power prices, but maybe I
should check that out.

>
> Baseline up to 1000kWh: $0.100030/kWh
> Over 1000 kWh: $0.120340
>
> (Yeah, I get really cheap electricity here in Florida--but it still seems
> high to me, as I was averaging around $0.085/kWh not long ago.)  See
> http://www.gossamer-threads.com/lists/mythtv/users/371460#371460 for details
> (and note that I did all calculations based on $0.10/kWh).  Even on a
> non-Myth system with only a mobo/CPU/RAM/and one HDD (that I measured after
> posting the other message), it's saving about $0.90/mo.  If you're paying
> more than $0.10/kWh for electricity, these values would increase.  In these
> cases--depending on the actual rate--the 80 PLUS Bronze/Silver/Gold PSU's
> may even be worthwhile, too (but check the PSU specs at the 80 PLUS site and
> do the math--preferably with real-world usage measurements--before choosing
> this approach).
>
> As for turning off your system when not in use, it's extremely easy to do
> this for dedicated frontend-only systems--just use mythwelcome and
> mythshutdown ( http://www.mythtv.org/wiki/Mythwelcome ).  Your backend
> machines can also be shut down, but doing so is more challenging (as you
> have to set them up to wake themselves when they're needed to record a
> show).  Again, see the info in the Mythwelcome wiki page for info.
>
> When 0.22 is released, you'll also be able to have Myth shut down all your
> backend machines.  The master backend will be able to wake remote backends
> on demand for recordings, so even if the schedule changes, you won't miss
> recordings.
>  http://www.gossamer-threads.com/lists/mythtv/commits/373731#373731
>
> Shutting down your systems when not in use will save you the most money you
> can possibly save--as power consumption goes to virtually 0 when the system
> is shut down.  Note, also, that you can swap out old,
> not-very-power-efficient hardware that wasn't designed for power saving
> (like my old Athlon XP systems) for new low-TDP Athlon/Core 2 systems;
> however, that option is more expensive.  As it is, my new PSU's will take
> quite some time to pay for themselves (and I got them all on sale for $29.99
> to $39.99 ea).
>
> Mike

Ah, I see you answered that question. Thanks!

Cheers,
Mark