Enfin is a self contained little village. We have our own:
-Power generation and storage
-Power transformation
-Fuel treatment
-Water maker
-Sewage
-Laundry
-Heat and Cooling systems
In short, a myriad of complex systems that make life comfortable, whilst -perversely- also making it more complex.
Taking them one by one:
-Power generation and storage
Enfin has 3 diesel engines. A main engine for propulsion, a wing engine as a backup should the main engine fail, and a generator.
Further, we have a number of batteries on board, but put simply, house and start batteries. House batteries are used for all comfort items, whilst the start batteries are reserved for engine starting only.
Any of the diesel engines can produce electricity. The main engine in particular has a large (280 amps!) alternator that can recharge the batteries when we are sailing, whilst the generator can produce up to 8KW of power feeding 2 chargers. It's our small electrical power plant.
So, on the one side, 3 producers of electricity. On the other side, 2 main banks of batteries (there are more but don't want to lose you!). All producers recharge all batteries automatically whenever they are in use, but when needed only the house batteries provide power to the boat as the start batteries automatically disconnect when not in use to start an engine. Of course there are a number of overrides and by-passes to connect everything for emergencies.
-Power transformation
Enfin's batteries are 12V DC (Direct Current). That means that to operate normal household items running at 120V AC (Alternative Current), electricity stored in the batteries must be "inverted" from 12V DC to 120V AC. We have a 3KW inverter that feeds a number of units, like the fridge, freezer, microwave and a number of normal household plugs around the boat.
At 3KW, the batteries are not powerful enough to run the larger electrical items such as the washer/dryer, the water maker, the A/C units and more. Those can only be used when the generator is running.
-Fuel treatment
Enfin stores up to 920 gallons of diesel, and to make sure it stays clean there are at least 2 fuel filters on each engine, plus a transfer pump with a large capacity filter to clean things up if needed.
-Water maker
Enfin has a 400GPD (Gallons per Day) water maker. Put simply it takes sea water via a primary pump, filters it a couple of times to eliminate the larger solids then feeds it to a high pressure pump though high osmosis membranes at 850psi.
-Sewage
All black water is collected into a special tank, later emptied using pump out stations.
-Washer / Dryer
Whereas ashore you'd just load your machine and press a button, the washer / dryer is a high electrical and water consumption item for us, so we have to plan its use. The generator must be running, and of course we must have plenty of water as well. Not usually a problem since we run the generator everyday and have over 200 gallons in our water tanks. Still, you must think before pressing the button.
-Heating and cooling
Enfin has both a Hurricane II hydronic heating system and 3 A/C units as well as a main engine heating loop. This is a very nice feature and allows for plenty of flexibility as well as remaining nice and warm in all conditions.
The Hurricane II is basically a diesel fed boiler that heats up a liquid loop circulating hot goodness around the boat where it is then exchanged back through fanned radiators into warm air. When it is running the boiler also heats the water heater. The boiler only needs basic 12V DC and does not need the generator to operate. We can stay warm in silence at anchorage.
The 3 A/C units can run in either hot or cold mode but need the generator running to do so.
When the main engine is running -on passage- the otherwise wasted heat generated by the engine is recovered via a heating loop. That loop heats the same liquid the boiler does, which in turn heats up the boat and the water heater.
And that's only a short and simple overview of the boat's systems!
Nothing too complicated once you get used to it, but being independent means more maintenance items and more work. It means thinking and planning ahead when using large electrical items or using a lot of water. Nothing is free in this world.