Independent buyer tools · transparent math

RV battery runtime and off-grid power planning

Work out what your battery can run before buying more equipment. Show the watt-hours, assumptions, and limits of every estimate.

Use the free calculator Our method

Example camping power components; installation details and safety must be checked for each system. Photo: Stephan Ridgway from Brisbane, Australia · CC BY 2.0 · resized and converted to WebP.

Start with the load, not a shopping list

A battery's amp-hour number is only part of the answer. Voltage, how deeply you discharge, system losses and the amount of time an appliance runs can each change the outcome substantially.

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Your complete RV power plan

List your appliances, compare solar and cloudy-day reserve, test equipment specifications and download a plan tailored to you.

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01 · Calculate

Battery runtime estimator

What can a 100Ah battery really power? Change the load, duty cycle and usable capacity.

Run the estimator →

02 · Recharge

Solar recharge estimator

Turn panel watts and peak sun hours into a rough daily energy budget.

Estimate solar yield →

03 · Decide

Monitor or power station?

Understand what monitoring does and where a DIY battery system differs from a power station.

Browse the guide →

Not a wiring design

The tools use arithmetic, not manufacturer performance testing. Real runtime changes with temperature, battery condition, inverter losses and appliance cycling. Use them for a first-pass energy budget; consult qualified professionals and manufacturer manuals for fusing, cable sizing and safe installation.

For a worked example, read how long a 100Ah battery may run an RV refrigerator.

Household outage planning

Which loads do you need during a power cut?

Build an energy budget and check the separate CPAP power questions.

Plan backup energy →

From research to decision

Turn your result into an equipment checklist

No fabricated product tests or affiliate claims. Compare verified specifications before buying.

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