If you’re always out and about like me, then you’d probably agree that RVing is one of the best ways to go. I’ve been RVing with my family and you may have read in my previous posts that I have kids and the youngest is 1 year old.

We’re about to go on another trip and I’ve realized how convenient it is to have all the things we need right inside our RV.

When it’s too cold, we can easily use the heater. When it’s too hot, the air conditioner is ready. 

We have our fridge full of everything we need for the trip. The microwave is there anytime we need it. The kids can even watch TV to keep them from getting bored. 

But have you ever wondered how we get to use all those?

Did you just say INVERTER? Yes, inverters are heaven sent for happy campers (glampers?) like us.

Before we carry one, I’ll answer the question “should I leave my RV inverter on all the time”. The answer is maybe. If your inverter is also a converter (more on that later in this post), then you will want it to be on all the time. If your inverter is only and inverter then you do not need it to be on all the time. Leaving it on will subject it to a lot of unnecessary wear and tear. It’s better to just turn it on when you need it.

But when do you need it? Read on my friend, read on.

Does My RV Have An Inverter?

Before we get into the details, let’s make sure first that we really have an inverter. Let’s not get too excited yet.

Okay, so I checked and found that most RVs have inverters. This means that they run on dual electrical systems – AC and DC.

  • AC (alternating current) systems are very much like what we can find in traditional homes and run almost anything.
  • DC (direct current), on the other hand, works just like automobiles. They function mostly on batteries, and will no longer run when completely discharged.

AC works by plugging your RV to an external power source and is what gives big appliances power as well. The air conditioner and the microwave run off the AC system. The same goes with power outlets.

DC, however, is only powered by one or two batteries and would only be able to give power to simple stuff like electric fans, TV, and the radio. The power that this system gives is limited by how much power the RV batteries have.  

If your RV works on these two electrical systems like mine, then you can confirm you have an inverter. If it only works on batteries, then you only have the converter.

On a semi-relevant side note, if you want to supplement your RV power needs you should check solar panels for your RV.

How Fast Will A Power Inverter Drain My RV Battery?

Since we plan to go on really long trips and the kids (and my wife) will probably need a lot of entertainment, chances are they will be putting a lot of load on the electrical systems.

But what if it drains my RV batteries fast?

The batteries are designed to give off a substantial amount of power for a short period and should not be drained more than a certain percentage of its total capacity. Otherwise, it will wear out more quickly than expected.

Given this, I find it better to think the other way around. Instead of asking myself how fast the inverter will drain my battery, I think it’s more important to ask how long I want my load to run.

More practical, don’t you think?

By calculating how long your load should run, you’re able to estimate the amount of time an appliance should operate. This way, you reduce the chances of your batteries dying on you when you least need it to.

Of course, you would have to consider your inverters type and size. If you have more than one battery, you’d have higher capacity, too.

How Long Will An Inverter Battery Last?

Same as above, it’s important to know the size of the battery bank and how much load is to be supported by the inverter. 

Again, the better question should be how long you want (or need) your load to run?

Based on this, then you can use specific calculations to help you determine your load.

The general formula is Volts x Amps = Watts or Watts / Volts = Amps

In this formula, the capacity of the battery is expressed by Amp-Hour (AH) capacity. This is technically understood as how many Amps for how many hours a battery will last.

If you are using a 12V inverter, then 100 watts of the inverter load requires as much as 10 DC Amps from the battery. On the other hand, for a 24V inverter, 200 watts of the load requires approximately 10 DC Amps. 

If you want an estimation of the load, you can check each appliance and add up the total requirement and work from there.

How Big Of An Inverter Can My RV Handle?

If we are living totally off the grid, then we would probably need a good sized inverter. But since we are just off for several days, then we won’t probably need that much.

But how much is good enough and how do I know it’s enough.

Well, we can always go back to the general formula: 

Volts x Amps = Watts or Watts / Volts = Amps

I already have a general idea of how much power we need, and I usually double it just to allow continuous wattage for startup requirements of some appliances like the fridge or the air conditioner.

For example, I checked on what we need as basics and I found the following estimation:

  • Microwave – approximately 500 watts
  • Fridge – approximately 1000 watts
  • Air Conditioner – approximately 2300 watts (1700 watts to start it up and another 600 watts to keep it running)

That’s a total of 3800 watts. Which basically means I’ll need 3800 * 2 = 7600 watts.

Of course, my advice is to use the load sparingly because we’ll never know what might happen on the road.

Does An Inverter Draw Power When Not In Use?

When an inverter is left turned on but not in use, it will usually draw around 10W plus the extra watts the inverter needs to run. This is very minimal and varies from one inverter to another. The specs should be able to tell you that.

Circling back to what I said at the beginning, leaving your inverter on all the time will cause extra wear, which means it would need to be replaced sooner.

But there is a convenience factor. If you want to use an appliance or gizmo that requires AC power, then you’ll first have to go turn on the inverter and then use the appliance or gizmo. If you keep the inverter running, but idle, then you’ll have AC power whenever you need it.


Since you will be on the road, always estimate and prepare a little bit more than what you need. When in doubt, don’t overuse your inverter.