Man with a Mission (How to Make a Boat Greener and Energy Efficient), by Ben Ellison (continued)
Sailor-Style Air Conditioning
The main convenience Gizmo lost when the generator was arduously extracted from the engine room was the ability to run air conditioning without shore power. In fact, I also removed one of the boat’s two air-conditioning units, her second 30-amp shore power inlet, and at least 100 pounds of associated cabling. It’s been a lighter boat ever since, despite all the added electronics, and about 1 knot faster at wide-open throttle.
Even Maine has suffered longer heat spells in recent summers, and we’ve learned to appreciate the heat-blocking properties of the white, exterior mounting “Florida curtains” that came with the boat. Twelve-volt fans also help, but the killer air-conditioning replacement is a light gray Sunbrella awning I designed with help from a boat canvas shop last winter. It deploys in about five minutes and shades Gizmo’s forward cabin including three opening hatches and big forward saloon windows. It’s aerodynamic enough to handle a near gale at anchor and to shed the thunderstorm downpours that often end a sweltering day. This is effective, low maintenance, zero-power sailor technology that deserves more attention from powerboaters, which may be why the awning often draws more attention at marinas than my many radars.
No generator also means no backup if the batteries go flat. But Gizmo has a separate engine-starting 12-volt bank and alternator, which I keep a close eye on, and I’m always aware of the house battery voltage thanks to daily cell-phone texts from a Siren Marine monitoring system. In 2013, for instance, I had to ask a friend to drop a few bags of ice into the freezer because I was worrying about the house bank going flat while I was vacationing in Sweden during a protracted Maine fog event.
Charging the house bank with the main engine is also fairly quick now because I had the 140-amp alternator rebuilt and replaced its conventional regulator with a much smarter Balmar 614H model. But of course the less power you use, the less you need to make, and Gizmo has slimmed down in that department too.