Last updated: October 6, 2026
The sizing formula already on the homepage and on how to calculate battery bank size is:
Ah = (Wh/day × autonomy days × 1.25) ÷ voltage ÷ depth of discharge.
The steps are the ones on that six-step page. You enter daily watt-hours, autonomy days, voltage (12 V, 24 V, or 48 V), and depth of discharge. The page divides by 0.80 for LiFePO4 and by 0.50 for AGM or lead-acid. The 1.25 is this site’s margin. It is not a manufacturer rating. At 12 V the six-step form also counts how many 100 Ah batteries in parallel cover that amp-hour result. Series wiring does not multiply amp-hours.
The weekend cabin inputs on those pages are 1,000 Wh/day, 2 days, 12 V, and 0.80. (1,000 × 2 × 1.25) ÷ 12 ÷ 0.80 = 260.4167 Ah. The same inputs at 0.50 are 416.6667 Ah.
Jeremy is a data/software person, not a licensed electrician or solar installer. These are planning tools, not professional advice.
Each guide links the government, extension, or manufacturer page it quotes. Price checks are dated on the page that uses them. The 12V LiFePO4 battery spec chart copies values exactly as published. Every row links its source document, the access date is on the chart, a missing value says “not listed,” and nothing on that chart is estimated.
Page text is drafted with AI agents (Cursor and local models) from those sources. Compiled with AI assistance from the sources below. Spot an error? Email jpanasuk@gmail.com.
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