Running TV from Portable AC/DC Inverter While Boondocking- How Inefficient Is This?

[mrpettit]

I'm boondocking and wanted to watch some TV.

My TV runs on AC power. So I took my AC/DC converter from my car plugged it in to the RV DC plug and plugged in the TV.

If I want to watch TV while boondocking is this something I should keep doing or does it drain a ton more battery than if I bought a DC TV?

[AnnArborBob]

Your 110 volt TV using the car inverter surely uses more of your battery capacity than would a similarly sized 12 volt TV because of the inefficiencies of the inverter process. The loss may not be all that significant in terms of amp hours, however, as the inverter loss is usually in the 10 to 15% range but since your TV does not use all that much power, 10 to 15% of a small amount may not be significant.

I'd be more concerned that your car inverter is likely a modified sine wave inverter and not a pure sine wave inverter (more expensive, of course.) Over time, a modified sine wave inverter could damage sensitive electronics such as your TV.

If you are interested in learning more about modified sine wave vs. pure sine wave inverters, use the "search function" on this site.

[idroba]

Inverters today are quite efficient, in the 85 to 90% range. Televisions have some kind of power supply built in to suit their electrical needs. They do not inherently operate on 12 volts DC, so even those 12 volt units may convert their power system from 12 volts.

Bottom line, there could be some efficiency gain on some Television Sets, but there is no guarantee.

That said, the WFCO sine wave inverter supplied with the Airstream inverter package requires almost 2 amps just to be on, so it is not one of those modern efficient inverters I mentioned in the first paragraph. Many of the small, less than 200 watt modified sine wave inverters you can buy for under $30 are a better bet, as they have a standby loss of under 0.4 amps. They will also operate your television just fine.

To all: don't leave your inverter on when not using it, and don't run it to do things like charging your phone. The standby losses of most pure sine wave inverters are quite substantial. A 2 amp load 24 hours a day is 48 amp hours. One group #24 battery only has a total capacity of about 75 amp hours.

I know that my statement seems contradictory. An inverter running a television is ok, but only if you shut it off when not in use, and it would be best if it were not a large pure sine wave inverter, as most of them have substantial running loss at low loads. The 300 watt Morningstar Pure Sine inverter is one of the few exceptions I have found to that statement. Small modified sine wave inverters are actually better for low load use.

Ask a question, get too much information, I know. Sorry, I just have to be complete.

[idroba]

PS: it is very rare for a television or any modern power supply to be damaged by a modified sine wave inverter. A few drill battery chargers a number of years ago had that problem, but most things have been designed differently for quite some time.

[Ahab]

Why don't you purchase a TV that runs on 12VDC and be done with it? I think I paid $149 for mine with a integeral DVD player and never looked back.

[Nmengineer]

The newer LED tvs are more efficient than older units and should be part of the solution. The solar package on our Airstream gives us a complete charge every day and more than 2 hours of tv usage without issue in the evening. Yes turn off the inverter when not using it!

[m.hony]

There are 12 volt televisions available. A 12 volt TV would take away the need for the inverter.

[FreshAir]

We run a 22" flat screen TV with Directv satellite, or a DVD player off a 800 watt inverter. We can watch a 3 hour movie from the DVD player and leave the house battery with a safe minimum charge until the next generator charging usually in the morning. Satellite TV watching is limited to just favorite programs.......after all we are CAMPING.

Neil

[HiJoeSilver]

Absolutely nothing wrong with what you're doing. As mentioned just unplug it when not using it to keep standby losses from draining the battery. This is what I've done, those 1000w inverters are overkill. I've used one of those small 200 watt portable car inverters and plugged it in on the occasion to watch tv or charge laptop. I use 12v to USB adapter, or USB port on stereo for things like charging phone/ipod etc, more efficient than going from inverter for those.
You may be surprised at how little power a led tv uses. If you can adjust brightness, turn it down for even less.
At home I used a killawatt meter on my 42" tv and was able to tweak it to use about 75w.