How to Size a Solar Generator for Your RV: A Practical Guide

Quick Answer

To size a solar generator for your RV, first add up the watt-hours you use daily, then multiply by 1.5 to 2 for inefficiency and cloudy days. For most RVers, a Yeti power station between 300Wh and 3000Wh plus matching Boulder solar panels provides reliable off-grid power. Start small if you just need to charge phones and run a fan; go larger if you plan to run a mini-fridge or CPAP.

When you're planning to boondock or dry camp, a solar generator can be a game-changer. But choosing the right size isn't just about picking the biggest battery you can afford. You need to match your daily power consumption with the amount of solar you can realistically collect, especially if you're parked in the shade or dealing with overcast skies.

This guide walks you through a simple process: estimate your RV power needs, translate that into watt-hours, then match a solar generator and solar panels that fit your space and budget. We'll also cover common trade-offs, like portability vs. capacity, and how to decide between a compact unit and a larger home-backup-style station.

Step 1: Calculate Your Daily RV Power Needs

Start by listing everything you want to power: phones, laptops, a 12V fridge, LED lights, a CPAP, or a small TV. Each device has a watt rating, usually printed on the label or in the manual. Multiply watts by hours of use per day to get watt-hours (Wh). For example, a 60W fan running for 5 hours uses 300Wh.

Add up all your devices to find your total daily watt-hours. This is your baseline. Remember that some devices, like refrigerators, cycle on and off, so use their average running watts, not the startup surge. If you're unsure, add a 20% buffer to your total.

• Use a watt meter to measure actual consumption if you have one.
• Consider seasonal changes: heating and cooling needs vary.

Step 2: Choose the Right Power Station Capacity

Once you know your daily watt-hours, choose a power station with at least that capacity, but ideally 1.5 to 2 times more. This accounts for inefficiencies, cloudy days, and the fact that you shouldn't regularly drain a battery to zero. For example, if you use 500Wh per day, a 1000Wh station gives you comfortable headroom.

For light use like charging phones and running a fan, a compact 300Wh station like the Yeti 300 (OPEN BOX) is enough. For running a fridge or CPAP overnight, you'll want something in the 1000-2000Wh range. For full RV living with multiple appliances, consider a 3000Wh+ station or a home backup system.

• Yeti 300 (OPEN BOX): 297Wh capacity, ideal for weekend trips and minimal power needs.
• For longer trips, look for stations with LiFePO4 batteries for longer lifespan.

Step 3: Match Solar Panels to Your Power Station

Your solar panels need to replenish your battery each day. A general rule: panel wattage should be at least 1.5 times your daily watt-hours divided by peak sun hours (usually 4-5). For example, if you use 600Wh per day and get 5 peak sun hours, you need about 180W of solar.

Portable panels are easy to set up and adjust, but if you have roof space, a fixed mount like the (3) Boulder 100 Solar Panel Mountable Bundle can provide consistent power. This bundle includes three 100W panels, a combiner, and extension cable, making it a solid choice for van builds or RVs with roof mounting.

• Check your power station's solar input limit to avoid over-paneling.
• Consider panel efficiency and weight if you're mounting on your RV roof.

Step 4: Consider Your RV's Space and Setup

RVs have limited space, so think about where you'll store and set up your solar generator. Portable stations can be tucked under a seat, but larger ones need dedicated space. Solar panels, whether portable or mounted, take up roof space or require setup time at camp.

If you're handy, you can install a roof-mounted system with brackets and cables. The Boulder Charge Controller Mounting Brackets are a low-cost way to secure your charge controller to the panel, keeping your setup tidy. For portable panels, look for ones with kickstands and weather-resistant construction.

• Measure your roof space before buying mounted panels.
• For portable panels, check the cable length to ensure it reaches your power station.

Decision Rules for Sizing Your RV Solar Generator

• Daily Energy Use: Calculate your total daily watt-hours. If under 300Wh, a compact station like the Yeti 300 (OPEN BOX) works. If 500-1000Wh, choose a 1000-1500Wh station. For over 1500Wh, consider a 2000Wh+ system. Always add a 20% buffer to your daily total.
• Solar Input: Match solar panel wattage to your daily needs and available sun. For 600Wh/day, aim for at least 200W of solar. For 1000Wh/day, consider 300-400W. More solar is better for cloudy days and faster recharge.
• Space and Portability: If you have roof space, a mounted bundle like the (3) Boulder 100 is efficient. If you need flexibility, portable panels are easier to store and position. Measure your RV's roof and storage areas before buying.

Product Facts

• Yeti 300 (OPEN BOX): This 6th generation 297 watt hour compact and rugged power station is designed for all your outdoor adventures. It’s versatile enough to help out during a power outage at home and tough enough to handle mud, dirt, dust, water, and more when you head out. It also has upgraded LiFePO4 battery technology for a long lifespan. For RVers with minimal power needs, this compact station offers durability and a long-lasting battery, making it a great entry point.
• (3) Boulder 100 Solar Panel Mountable Bundle: Three Boulder 100 Solar Panels, a 4x 8mm High Power Port (HPP) Combiner, a 30 ft. HPP Extension Cable, and mounting brackets – this kit is essential for any van build or home backup. Each 100-Watt panel features an integrated kickstand and is built with strong tempered glass and an aluminum frame. This bundle provides 300W of solar power, ideal for RV roofs, and includes everything you need for a permanent installation.

Who This Sizing Approach Fits Best

Best for

• Weekend boondockers who need to power phones, lights, and a fan
• Full-time RVers with moderate power needs who want a permanent solar setup

Not for

• RVers who need to run heavy AC or electric heaters (consider a generator or shore power)
• Those with very limited roof space who should stick to portable panels

Sizing a solar generator for your RV doesn't have to be complicated. Start with your daily watt-hours, add a safety margin, and then choose a power station and solar panels that fit your space and budget. Whether you go with a compact Yeti 300 (OPEN BOX) for weekend trips or a mounted Boulder 100 bundle for full-time living, the right setup gives you freedom from shore power without the noise and fumes of a gas generator.