Man with a Mission (How to Make a Boat Greener and Energy Efficient), by Ben Ellison (continued)
Generator Off, Solar Panels On
While removing Gizmo’s generator seemed like a radical decision, a significant motivation was its exceptionally noisy and difficult-to-service installation. However the overall plan embraced several ways to reduce the need for a generator, including the addition of solar panels. Again I had some extra motivation—Gizmo’s regular home is a moored float with no shore power—so the solar assist may be the improvement with the most bang and least hassle for the buck.
The twin Kyocera 140-watt panels and Blue Sky MPPT charge controller were conventional solar gear when I installed them in 2012, but I appreciated install guidance from the specialists at eMarine Systems. The setup cost about $1,500 including a hinged aluminum rack built by a local machine shop, which lets me move around the extended cabin top when needed and also supports the antenna mast when it’s lowered for winter stowage. When Gizmo is moored stern south I can even issue the salty command, “hoist the panels, matey” to improve performance.
While it’s not uncommon to see more than 20 amps coming from the panels when the sun is high and astern, it’s perhaps more important that even low light yields a charge which is not drastically reduced by antenna mast and flying-bridge shadows. (Gizmo’s greener simplicity is superficially masked by the extreme profusion of marine electronics that I test onboard.) On the other hand, the fast-moving shadow of a large American flag can significantly reduce performance, but that’s the only aspect of this solar system I’ve ever had to manage. Except in the dark, the 12-volt juice has been quietly flowing since August 2012, and even kept the batteries up during a winter when the boat was shrouded in white shrinkwrap at about 45 degrees North.
For 2½ boating seasons now, the sun has usually kept Gizmo’s batteries topped up at her float despite the serious draw from the refrigeration system, various always-on communications devices, and my frequent visits to putter with electronics or use the boat as an office. When cruising we can often spend at least 24 hours at anchor without rationing power harshly or running the engine. And when the boat is tied up at a southern marina with metered shore power, that portion of the monthly bill is trivial.