Solar kayak - new propeller test

DIY 18V electric outboard motor. HRS 775 cordless drill motor and gearbox, APC 8" x 4" model aircraft propeller. 6kts with a brushless motor and new panel: https://youtu.be/6u-j1gxQRGc Trolling motor construction video: https://youtu.be/xgOfI49nCCM Nearly triple the propulsive power compared to the drone prop ( https://youtu.be/Yx29XnPp6Z0 ). Still no battery or MPPT electronics. I am well aware of the benefits of a battery and voltage control, but the aim of this project is to optimise the solar-motor-propeller match. That is where the engineering challenge lies, getting each component to simultaneously operate at their respective maximum efficiencies. Just pure, direct solar. Bollard pull showed 3kg static thrust. My homemade supercapacitor: https://youtu.be/04iWLRbRIhE It needs to be scaled up a lot before it will be of any use on the kayak. The solar panels have since been replaced with a 300W mono-crystalline smart panel and MPPT controller. The brushed motor has been replaced with a brushless motor and an entirely new drive train: https://youtu.be/wys0oQKtMpM