How Many Amp-Hours Do I Need For My RV

Recreational vehicles are battery consumers and most of them also have access to modern conveniences for more comfortable trips. With a multitude of differences in the aspects of getting away, RV consumers have certain and in many cases, lots of needs for power.

How many amp-hours do I need for my RV


Batteries in recreational vehicles use the lead-acid concept. They are made of lead and lead oxide plates submerged in 36% sulfuric acid and 64% water acting as the electrolyte. They have several cells connected in series with each cell producing 2.1 volts approximately. A 12-volt of the lead-acid battery produces 12.6 volts of total output voltage while six cells are put in series.

Lead-acid batteries are used technically for their potential of storing electricity instead of making it. As a result, the lead plate sizes along with the amount of electrolyte decides the amount of charge a battery can store. You want to have a gist on how many amp-hours you need for your RV.

Notably, to estimate daily amp usage, usage hour alongside amps per hour is required. The consumers of such vehicles will require to both generate and store power for achieving benefits from its usage as per needs.

How to Determine How Many AMP Hours You Need For Your RV

When planning alternative energy almost everyone underestimates the amount of electricity consumed. Determining RV amp-hour usage without having to run the generator while living by the sun can seem like a frustrating job. Figuring out the daily amp-hours totals of the electrical power you use up is a must before you can start to plan. Unfortunately, an ideal case of a fixed calculation is not applicable in this case because it is largely different for everyone. It is very important to have complete knowledge of watts as well as watt-hours as an RVer and this article covers that as well. Determining the watt rating of the must-be-used equipment or an appliance is necessary to pick up how much a particular appliance consumes over a period of time, namely watt-hours.

Firstly, your job is to calculate how many amps you consume daily by calculating amp usage by hours used. Therefore, you have to compute the watts and voltage mannerly for each equipment and each appliance. Know that watts are typically expressed as operating voltage multiplied by amp draw of an appliance. Therefore, you can regulate amps from watts/volts. For example, a 120-volt toaster with an amperage draw of 9 amps will take 1080 watts.

Mathematically, 120 volts * 9 amps = 1,080 watts.

However, include the 12-volt appliances in the calculation as well. For example, if a 12-volt RV furnace has an amperage draw of 7 amps then it uses 84 watts.

Mathematically, 12 volts * 7 amps = 84 watts.

From that fact, if you have settled your RV uses up approximately 2,100 peak watts of power typically, you can, without worrying, use a 20-amp electrical outlet.

Mathematically, 2,100 watts / 120 volts = 17.5 amps which is less than available 20 amps providing a comfortable extra power margin.

You can see a video discussion about How Much Battery Power Your RV Needs:


Secondly, the amperage draw for some appliances varies depending on their usage. Such as, a flat-screen TV allows brightness adjustments of the display inclusive of volume control. The total amount of amps consumed by the TV or such appliance, in turn, will be regarded in the first place to power it. Most packaging tends to contain every needed information or you can, of course, look it up online. 

For appliances that cycles on and off, such as, refrigerator consider purchasing a watt meter to know the watt-hours. You can plug your entire RV or a 120-volt appliance into a watt meter over a set period of time to measure consumed watt-hours. Be careful not to exceed the meter’s rated amp capacity. Other than that, a battery monitoring system will come in handy deciding how much power your equipment uses. For example, switching on the gas furnace will show the current reading of consumed amps on the attached battery monitor. However, battery manufacturers usually recommend only using half of the available battery capacity as it extends the battery lifetime. That is, if you decide you require around 200 amp hours then you will have 100 available amp-hours.

Estimating Your Amp Usage

Your battery bank is told to size to match the estimation of daily consumption of power. Start with considering relevant electrical items you will be needing and how long you intend to use them in a typical 24 hour period. Determine how much amount of current each required piece of electrical equipment generally uses. You have to perform the computations in amp-hours as your motive is to find the total amp-hour for your RV.

Finally, total the hours and afterward, compare it to the amps per hour capacity provided by your fully charged battery bank. As a first-hand tip, it is easier to convert both DC and AC measurements while comparing them to watt-hours. Also, a short burst of excessive current is pulled by the starting compressor on an air conditioner to get things turning. Once you have successfully determined and added the amp-hour requirements of each instrument that will be running altogether your RV, you will know your shore power needs as expressed in watts.

To conclude, the illustration in this article about learning to calculate amp-hours and estimating your needs should suffice. In reality, however, more things may end up drawing battery powers.