It’s been a few years since I hatched the wild idea of building an electric boat I could use for lobster fishing. Phase one was in 2011 and consisted of planning, building and powering up. Except for an initial problem of backward steering things went pretty well. That fall I was already preparing for phase 2, the roof. That would allow me to build in a boom for hauling lobster traps and the roof would serve as a platform for eventual photovoltaic panels. I was unsure if the boat would take kindly to the added weight aloft, but all went well. By summer of 2012 I was hauling traps and enjoying the shade and shelter of a roof. I also added reverse.
Now it’s August of 2013 and I finally decided to bite the bullet and try to come up with a way to use the sun’s energy to allow me (more or less) unlimited range. I rejected conventional panels, which use heavy frames and glass, in favor of new ultra-thin plastic panels. These have only been available for a few years, and the marine version is incredibly expensive (of course!). If you want a panel made in Germany or Italy marketed to sailors it will cost you $900 for 70 watts, or nearly $13/ watt! This at a time when rooftop panels are closing in on $1/watt. Fortunately, the Chinese are making them too, and I was able to buy six 80 watt panels for $1.60/watt plus shipping from Hong Kong. I don’t know if these lightweight panels are going to last more than a few years, but I don’t have a lot of choices.
I had a heckuva time arranging the right sized panels to my roof area and power requirements. I wanted 400 watts. I also needed a charge controller to safely get the solar power into the batteries. All these things made me give up several times. I’d find panels that worked but couldn’t match the voltage. I’d find a 36 volt controller but it wouldn’t do 15 amps. And on and on. I learned a lot too, like you can’t mix different sized panels, and you need a panel output (VOC) of around 20 volts to charge a 12 volt battery. Finally it all fell together with help from Jason Huang at Sacred Solar, John Drake at solarseller.com and the folks at Solar Converters, Inc. The whole price tag was just under $1400, about $400 more than my limit, but I ended up with 480 watts. And now it’s done. After part of two days in tossing seas I completed the installation, and today I found out what it was like to cruise on sunlight alone. The controller is taking the output from the panels, boosting up the voltage to a maximum of 44 volts and keeping my batteries happy and well fed. I left the boat with the battery bank at 92% and returned two hours later with it at 98%. That’s about 432 watt hours from a partly cloudy day, or 4 miles at 4 MPH. Now all I need to do is to figure out a way to keep the gulls from pooping on my panels.
I have no illusions that local commercial fishermen will see my set-up and immediately convert their roaring diesel lobster boats to solar, but it’s a start. I only have 5 traps and would not try to fish 150 traps with this solar boat. Still, the lobster boat of the future may indeed have a few features of Eleccentricity. Besides, I’m having fun. Oh, and when I reported earlier that I could check my traps for 2¢ worth of electricity, well now that’s 0¢, unless you factor in the $1400.