Time 0140 local
Lat N 27° 30.0′
Lon W 71° 09.9′
Nautical miles from Great Harbor, Jost Van Dyke, BVI: 648
Nautical miles to Sandy Hook, NJ: 791

The wind might drive Harmonie across the ocean, but electricity makes her work. Of course electricity is used for things you find on most modern boats, like refrigeration, but is also used for a lot of the heavy lifting in sail handling, the auto pilot, and for the watermaker. So a lot of time and thought goes into generating, storing and using electrical power.

A bank of 12 Group 37 batteries stores the power. Unusually for a boat of her size, the main D.C. power distribution is 24 volts, not 12. But of course batteries don’t make power, they only store it. Power on Harmonie is generated in two ways.

First is a six kilowatt Onan diesel generator. In the original factory design, this was the only source of power on the boat. The second system is a 615 watt bank of solar panels we installed last year.

A day in Harmonie’s power cycle looks like this: First thing in the morning I start the generator and run it for about an hour to replace the bulk of the power drawn out of the batteries overnight. If we need to make water, that happens at this point since the generator can make more power than the batteries can accept. An hour’s run time uses about a pint of diesel fuel.

Once the batteries are mostly charged, the solar panels take over. They supply all the power we need during the day, with enough left over to bring the batteries up to full charge. On a typical day the panel will generate 2.5 to 3.0 kW-hrs depending on weather and our usage.

Speaking of usage, when we are anchored our biggest consumer by far is refrigeration. Second is the watermaker. Third… well that almost doesn’t matter!

Our sailing day today was probably what people imagine when they talk about sailing being peaceful and quiet. Winds a bit lighter, speeds a bit slower, but we’re moving in the right direction, it is beautiful, and a comfortable ride.