Jadralski blog

Sizing your sailboat lithium battery bank — Skysat workshop method 2026

Choosing 200 Ah of lithium for a 40 ft sailboat is easy. It’s also probably wrong. The Skysat workshop method has 5 steps: 24 h energy balance per load, simultaneity coefficient, safety margin, useful DoD, final capacity selection. Worked examples for 30 / 40 / 50 ft sailboats in coastal vs offshore cruising. The right sizing costs 30 % more to buy and 50 % less in usage frustration.