When one thinks about the type of boat to buy for cruising, design, size, and where you are going to use the boat are all considerations. Other considerations that greatly impact comfort while living aboard are how you set up your electrical/charging system.
I have met a solo sailor living aboard a 68′ vessel that was extremely well equipped. With every modern convenience available, from ice maker and A/C, to expresso machine and hot tub, this boat had it all! The only thing that was kept to a minimum was conservation itself. The generator ran constantly, along with three refrigerators that were mostly empty. The interior was massive, with four staterooms each with their own separate (electric) head and shower. A salon that could easily seat ten comfortably and a galley that was as big as most kitchens in a house, there was plenty of space and amenities to say the least. On the other hand I have been witness to a family of four living aboard a boat that couldn’t have been more than 32′ in length. Since it had no refrigeration or auto-pilot and very few other electrical devices, a 100 watt solar panel was used to charge a single house battery.
Most cruisers comfort levels fall somewhere in-between. I remember when I bought my boat, how important the 7.7kw generator was to me. How else would I run the air conditioning when disconnected from shore power? I thought that I would die without it! Truth is, you rarely need air conditioning while away from the dock. However because of my 120 volt refrigeration system, I still had to run the generator for about two hours a day. Each day would begin and end with the sounds and smells of a diesel generator. This was not helping with the zen like state that I was trying to achieve! Not to mention the residual heat that was created, (now I really did need air conditioning). Due to its age and ongoing mechanical issues I chose to get rid of the diesel generator.
The previously inaccessible space between the stringers now contains eight golf cart batteries.
I replaced the 120 volt refrigerator/freezer with a couple of 12v units. I wanted to utilize solar and wind power for recharging the batteries. We have 390 watts of solar and an AirBreeze wind turbine with The Silent Wind Blue Blades. In addition to this we have a Honda EU2000i generator/inverter. Combined with a Magnum 50amp charger/2000 watt inverter and a Balmar 100 amp alternator, they keep the 880 A.H. house bank topped up. The Honda is also capable of running the 12k BTU air conditioner. The less that I have to run the engine or generator the better. However there are times when the sun doesn’t shine and the wind doesn’t blow, just not very often in Da Caribbean. After spending the last 12 months on anchor, if I were to change anything at this point it would be to add another solar panel. I believe that about 550 watts total would be better suited towards meeting our needs. Most of us have to balance wants and needs with a consideration to our budget, but power reserve on a boat is like money, you can’t have too much. You’ll find the more that you have, the more you spend/use.
My system is setup in such a way that the load is shared. By doing it this way I’m not completely reliant on any one charging source and more importantly,” I have peace and quiet”.
12 v. devices used while on anchor include: TV (movie night) 5amps/Hr 2Hr/movie = 10 amps/week underwater lights (entertainment/fishing) 5amps/Hr = 20 amps/week 12v watermaker 6 GPH. 11 amps/Hr = 132 amps/week refrigerator/freezer @ 7 amps/Hr = 1176 amps/week interior lights LED = 7 amps/week anchor light LED = 17 amps/week freshwater pump = 12 amps/week Total amp/Hr used = 1374 amps/week -196 amps/day 390 watts of solar average = 730 amps/week – 104 amps/day Air Breeze W/silent wind blades average = 460 amps/week – 65 amps/day