Camping Interior TV Installation
TV - Ohms Law Counts
If you're running off your leisure battery, the average portable TV consumes anywhere between 3 and 5 amps. This will soon run a leisure battery down unless you have a substantial battery setup or have discovered the holy grail and have a portable TV that consumes milliwatts instead. Its as well to remember this if you have visions of a cinema-style experience. TV manufacturers don't have masses of incentive to make 12v TVs that are ultra-efficient as the parts generally cost more, and without a big demand from consumers, it is not top of their priority list. There are however, a handful of low-power TVs with and some consuming as little as 1/2 amp. The cost may be prohibitive so do your research. You also need a good signal - from somewhere. Ohms Law (look online for a calculator if your maths isn't up it) is your friend here. Many TVs only specify watts, but with this figure and 12.5v, you can soon calculate how many amps a TV consumes. 1 amp or less should really be your aim.
Energy Efficient Alternatives
The alternative, and the easiest to connect as well as being very energy efficient is a large tablet or hybrid notebook that is charged via a micro-usb port rather than common laptop power connections. The reason for this is it avoids having to mess with possibly a ver inefficient power supply and since its a micro-usb and it only needs 5 volts. The power demands are exceedingly low. Some tablets now have battery lives of 10 hours or more which easily covers a nights viewing. The downside (depending on where you are) is unless you have a good data connection via a mobile phone, you can only watch pre-loaded movies - say in MP4 format. You could also plug in a USB TV Dongle (around £10), again if signal strength is good. I use a tablet which only consumes 0.14 amps - negligible. Those that prefer to be more self-suffient asnd may even have solar panels - tablets make a great alternative.
If you have mains hookup every time then you can fit what you like.