So far we’ve looked at how to deliver supplementary power when at rest, a difficult enough challenge with today's complicated boats, but one which pales into insignificance when underway 24 hours a day, when many other ‘hungry’ devices are factored in – the autopilot, navigation lights, instruments, etc.
This was our stumbling block, as whilst we’ve always been able to meet our daily needs with wind and solar when at anchor, we’ve struggled when passage making, and had, on occasion, to run the engine for a couple of hours a day to generate electricity. And this despite the fact that we use our windvane over our autopilot, use only an LED navigation light, and shut down our navigation system to the bare essentials when offshore. Solar can only do so much, and wind generators are at their least effective downwind – and who likes to go upwind?