Choosing Between 12V and 24V Systems in Your RV: What You Need to Know

Choosing Between 12V and 24V Systems in Your RV: What You Need to Know

When planning an RV power system upgrade, many RVers face a common question: should you stick with a 12V system or move to a more powerful 24V setup? In this blog, we’ll walk through a real-world example shared by Todd from NRVTA in a recent Two-Minute Tech Tip Tuesday, where he and Joe upgraded an RV with a dual-inverter 24V system—and addressed how to run 12V appliances off 24V batteries.

Why Consider 24V in the First Place?

Most RVs come standard with 12V systems, but when you’re adding more powerful equipment—like dual inverters or planning for off-grid living—24V starts to shine. A 24V system is more efficient than its 12V counterpart, typically offering 3% higher output (95% efficiency vs. 92%). While that might not sound like much, over a full battery bank, it can add up to significant runtime.

Also, 24V systems draw half the current of 12V for the same amount of power, which means your wiring runs cooler and your batteries are under less strain.

How Do You Run 12V Appliances on a 24V System?

One of the biggest challenges is powering standard 12V RV appliances—like your lights, water pump, or slide motors—from a 24V battery bank. Todd outlines two reliable options:

Option 1: Use a DC-to-DC Converter

Victron makes an Orion DC-DC converter that takes 24V input and outputs 12V power, up to 70 amps. This is ideal for running standard 12V loads in your RV. However, if you’ve got heavy loads like hydraulic jacks or onboard generators, 70 amps might not be enough—you may need to install two converters in parallel.

Option 2: Keep a Dedicated 12V Battery and Converter

Another method is to let your 24V batteries power your 120V inverter system and keep a small 12V battery onboard. When the inverter is on, your existing 12V converter can still charge that battery and power your 12V devices. It’s not as “clean” as one integrated system, but it works well—especially if you want to avoid stressing a DC-to-DC converter with high initial loads like slide motors or generator starts.

Common Misconceptions

Some people argue that running both 12V and 24V systems is against electrical principles—but it’s not. It’s simply two separate systems coexisting in your RV, and it’s more common than you think in advanced solar setups.

Where’s the Cutoff Between 12V and 24V?

Todd offers some helpful guidance:

• Stick with 12V if you’re running a single 2400W inverter or you’re on 30-amp service and want to maximize that power.

• Go with 24V if you're running dual inverters or anything over 5000W.

• Skip 48V in most RVs, unless you’re in a tiny home or full residential rig—it’s harder to install and manage the larger battery bank size.

Bonus: Solar System Efficiency

One benefit of higher voltage battery banks is improved solar performance. The same Victron solar charge controller can accept more solar wattage when running at higher voltages—so 24V or 48V lets you use fewer charge controllers while pulling in more power from your panels.

Bottom Line:

Choosing between 12V and 24V comes down to your RV’s size, energy demands, and how you plan to use it. If you’re running bigger systems or going off-grid, a 24V setup is well worth considering—and knowing how to safely power your 12V appliances is critical.

If you’re looking for expert help designing your RV power system, Big Beard Battery has your back. From complete off-grid systems to hands-on install clinics, we help you build your setup the right way. Learn more at BigBeardBattery.com.

Need help with your RV electrical design?Drop your questions below or reach out—we’re happy to help you power your journey with confidence.