Guide topic
Off-Grid Solar Sizing
Plain-English, source-cited guides to sizing solar and batteries for a van, RV, or off-grid build.
Guide
How many solar panels do I need?
Size an array from your daily watt-hours, peak sun hours, and system losses — with a worked van example.
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Guide
What size battery bank do I need?
Amp-hours, days of autonomy, and why LiFePO4 and AGM give very different answers.
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The app for this
Watt: Off-Grid Solar Calculator
Enter your devices and location and Watt sizes the whole system — solar array, battery bank, charge controller, and wire gauge — with every assumption shown. For van, RV, and off-grid builds. Free to download.