Solar on a Boat!

This boat owner dreams of wintering in warm Caribbean waters (and as the sun currently sets in the FLX before 8:00 p.m., well, so do we). However, their dream would be rudely interrupted by a) frequently running loud diesel engines or b) repeatedly tethering to shore to recharge batteries.

Off-grid on a boat? Absolutely!

ahoy, solar panels!

(Sidebar: this year, we’ve done solar on a van and now solar on a boat – who needs solar on a plane? or a train? on a box? with a fox?)

Originally, the boat had two diesel engines, whose alternators charged two engine batteries (providing DC power). A house battery provided AC power via a marine inverter for general living requirements.

Dave and the boat owner expanded this system by mounting two solar panels, leveraging existing hand rails.

module rail mounted to hand rail

Since the purpose of the project is to provide clean, quiet energy when the motors are not in use, the solar panels charge the house battery (instead of the motor batteries) via a charge controller and switches (to provide ground-fault protection and output breakers). The house battery can, in turn, charge the motor batteries if needed.

balance of system components

This equipment needed to be mounted in a teeny tiny utility closet – more like a cabinet! The only way to make it all fit was to mount the charge controller on the door. Wire management was key.

left: door open. right: door closed

For Sungineer Dave, the most interesting part of this project was exploring the boat’s electrical system and reverse-engineering someone else’s thought process to understand how the system worked. The boat came with plenty of wires and cramped spaces, but did not come with an owner’s manual or drawings.

an exciting new view – different from the view from a roof!

We are grateful that the boat owner selected Sungineer Solar for this project and that we could bring him one step closer to his goals. We wish him clear skies, calm seas, and abundant sunshine in his future adventures!