My Electric Boats: First Steps

If you have an interest in quiet, clean and green propulsion for your boat, this book is the perfect place to start. It provides everything you need for a successful electric boat project.I started thinking about electric propulsion for boats about sixteen years ago. At the time, I owned an O’Day 20 ft sailboat. Knowing that an efficient hull was needed to propel the boat with as little power as possible, I decided to use the O’Day sailing hull to test the idea. The simplest solution was to buy an electric trolling motor and to put the two 12 volt batteries in series to provide 24 volts of power. At 30 amps, the input power to the motor was 720 watts or nearly 1 hp. (1 hp equals 746 watts.)

The results were under-whelming: at full power the boat moved at possibly 2 or 3 mph and lost steerage whenever the wind picked up. To a retired engineer, who loves everything about boats and has time on his hands, the seed of a challenge had been planted. After all, 1 hp was the equivalent of 7 “manpower” and you would think that 7 rowers pulling hard could move a small boat fairly fast while keeping it under control. So, the question was how much power was needed to move a small boat at hull speed and could that amount of power realistically be generated electrically?

The answer is that 1 to 2 hp is adequate to achieve hull speed in a small sailboat.


Click here for the complete Chapter 6 "SUNNY II, a RHODES 19" from My Electric Boats in PDF.  

My Electric Boats book
2nd Edition of My Electric Boats