#4658 Solar-Powered Bay Boat
#4658 Solar-Powered Bay Boat #4658 What would be required for a solar-powered bay boat that can do 5 knots? Running a bay boat entirely or primarily on solar at a steady cruising speed of 5 knots (~5.75 mph) is a sweet spot for displacement efficiency, but water resistance still demands real power. To achieve a true "net-zero" 5-knot cruise under solar power (or a solar-assisted electric configuration with decent range), the core system requires specific sizing across propulsion, power storage, solar array, and hull considerations. 1. Propulsion: Sizing the Motor At 5 knots, a light-to-medium bay boat (18–22 ft) is typically operating near or just under its displacement speed. Drag increases exponentially as you try to push past this point. Power Requirement: Cruising at 5 knots requires roughly 2 kW to 4 kW ( $2.7$ to $5.4\text{ HP}$ ) depending on displacement, beam width, and wind/current conditions. Motor Setup: * A 3 kW to 6 kW (48V) electric outboard or pod driv...