Originally Posted by jwedell
I installed a few hd 12 volts outlets (used #10 wire) Most of our items are 12 volts. The tv and sat box were 120 volts. When we boon dock we use a small plug in inverter and plug the tv and sat box into it. Works great for us. Dw uses a 12 volt cpap so no problem.
Best Buy has a few decent TV's that run off of 12v (they come with laptop style AC plugs that output 12v). I picked up at 24" model with built in DVD player as seen in my previous pictures for $130 recently and then picked up an adapter plug for $20 at radio shack (probably could have gotten it cheaper online if i knew the plug size).
Also if you use DirectTV (Im sure Dish as well does, a lot of the mini set top boxes don't have room for AC to DC transformers internally and take straight DC and put the transformer in the wall plug) I know that a few of their smaller boxes are 12v as well and use the same laptop style plug. So if you ever wanted to you could swap that out for 12v as well.
Here is where i am going to completely derail the conversation. I apologize to the OP; Please disregard as its not specifically relevant to the question. Just figured I would add some math and back ground info to why using 12v is much better when running from a battery
Due to the nature of electronics basically if its not a compressor or motor it runs on DC. The reason that we use AC in our houses is due to the fact that long range transmission of DC power has some technical limitations. its much more efficient to use DC especially with the efficiency losses with AC to DC conversion (most inverters / transformers are around 80-85% efficient if i recall correctly off the top of my head with the lost energy going to heat, this is why they are warm to the touch).
So if you are using an DC to AC inverter you are using 125% of the power required to charger your Laptop due to the power loss of the inverter. Then if you are using a AC to DC transformer to charge your laptop you are now using 156% of the required power to charge your laptop due to the secondary loss introduced by the second conversion.
Here are some examples. PC power supplies are some of the few transformers that publish their efficency ratings. HERE
is an example of an energy star rated power supply and it is rated as "80 PLUS Certified, with up to
80% efficiency under typical loads".
is a 400 watt inverter that publishes its efficiency rating. "Efficiency (full load, 12V): > 83%"