RVs use a lot of power and with all of our devices and added appliances, this power load increases. But you can't just use the power straight out of the shore power outlet for many of these electrical devices. RVs use two power systems, 12V DC power and 110V AC power. Converters are used to change the 110V AC power from the shore power to 12V DC power for your RV appliance and items such as lights, fans, vents, and more. The converter also works to recharge your batteries when you are hooked up to shore power, which means your batteries won't drain, further extending their lifespan. And since having access to battery power is so important for RV life, having a converter to charge the battery is equally important.