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

[Michael T. Dean]

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.

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

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