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RV Solar Sizing Calculator: Plan Your Off-Grid Power System
Estimate daily appliance energy, solar capacity, battery storage and inverter requirements for a caravan, camper or off-grid RV power system.
An off-grid power system should begin with the energy you expect to use, not with a panel or battery chosen in isolation. The free Solar Power Estimate Calculator—shown in the app as SPEC—builds a practical estimate from your appliances, usage and system preferences.
Use the result to compare scenarios and create a shopping shortlist, then allow for the real conditions of your trip: season, location, shade, weather, battery limits and the way each appliance is actually operated.
Open the free RV Solar Sizing Calculator →
Build the estimate from your loads
Choose the system setup, add each appliance and enter its power and expected daily runtime. The results update as the load list changes, allowing you to see which appliances drive energy consumption and what happens when usage assumptions change.
- Daily energy use in watt-hours rather than watts alone.
- A solar-array estimate based on the configured assumptions.
- Battery storage requirements and usable-capacity considerations.
- Inverter sizing context for AC loads and simultaneous operation.
- Scenario comparison before choosing equipment.
Follow the SPEC guided tour
Select the question-mark button to step through system setup, the appliance list, live results, comparison area, project actions and the option to email the design for human review. The tool switcher at the beginning also shows where roof layout, wiring and board planning fit into the wider workflow.
The appliance and results steps are a useful pair: one shows the assumptions you control, and the other shows the system estimate those assumptions produce.
Stress-test the result before buying
Create a normal-use scenario first, then increase the runtime of the largest loads or reduce the expected solar input to understand the margin. Check whether high-power AC appliances will run together and whether their start-up demand changes the inverter requirement.
Save the assumptions with the project so you can compare the estimate with real energy use after the first trips.
The result is an estimate, not a guarantee of generation or runtime. Confirm product specifications, charge limits, voltage compatibility, environmental derating, protection and installation requirements before ordering. Human review is especially valuable for systems with air conditioning or other large loads.
Shop the matching equipment
Use the plan to narrow your shortlist, then check the current product specifications and installation requirements:
Continue planning your RV power system
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Posted in
off-grid-power, rv-solar-tools, solar-sizing
