I haven't chimed in because it seemed you were keen to go a primary engine
/ genset route
but in light of your interest in the Dashew approach and the following quotes, I thought my experiences might be a useful datapoint:
With the exception of voyaging in the arctic, our boat
is similar to your desired specification with both my wife and I working remotely when we are on it and no desire to be frugal with the power. When we bought it, the boat
had a 1000Ah AGM battery
bank (Mastervolt) with two Electrodyne GE150-24V
brushless alternators on a custom mount attached to a Yanmar
4JH4-HTE 110HP engine
. The alternators were controlled by Balmar
voltage regulators and the system was designed based on the Dashew system. The system worked pretty well for the previous owners but there were some issues with the voltage regulators burning out. After buying
the boat, when my wife and I sailed it from San Francisco
to our home port in Puget Sound
we had the regulator
burn out again and we unfortunately did not catch the problem immediately leading to the batteries
being damaged. This led to us replacing the batteries
last spring with an OceanPlanet Energy / Genasun 1080Ah LiFePO battery
bank. We also have 540W of SunWare solar panels
you can walk on in 10 panels
mounted to the hard dodger
top and deck
, and a SuperWind 350 wind generator
. The system also maintains the stock 12V alternator
the separate engine battery.
After our first year of use, we are extremely happy with this system. While we were impressed with the alternators when we bought the boat, they have really come into their own with the Li battery bank. The alternators are rated at 150A each but put out about 340-350A (8.4kW) at typical cruising RPMs and at 2800-3000 RPMs I see a max output of about 375A (9kW) or 125% of rated output and they have done this for hours without breaking a sweat. This now means that in a typical 3-5 days we spend in one place while cruising the batteries may reach 20-30% SOC and then running the engine for 1.5-2 hours while moving to a new site brings the bank back to full charge, and I mean 95-100% SOC as there is no practical charge taper with these batteries until about 98% SOC.
My understanding is Electrodyne's primary market was (is?) US military and these alternators are designed to be incredibly robust. Being brushless, the only real point of concern might be the diodes exposed to heat and to address this Electrodyne mounts the diodes remotely. When we bought the boat, I called Electrodyne to ask if there was any type of service
I should perform since there was a little over 1,200 hours on the engine / alternators and five years since they were installed. The engineer
I spoke to paused thoughtfully and then said "Nope, in that application you might want to check the bearings at around 20,000 hours, but that's about it". I exaggerate not...
So given that background, our setup seems like it could fit your original premise of using "the same source of power for as many different systems as possible, then make that source of power as robust and redundantly supplied as possible." As you stated previously, the modern common rail diesel
is extremely reliable and field serviceable. With two primary charging
alternators and individual voltage regulators, you have some system redundancy from a DC power generation standpoint. And replacing an alternator
, voltage regulator
diode pack is a pretty simple operation if it becomes necessary. You also have only a single
engine to stock parts
for and maintain. The fuel
system is also somewhat simpler with fewer filters to maintain and less plumbing
to run than a engine / genset setup.
Attached are a couple of shots of the alternators, the first pre-install so you can see how they are mounted to the engine and the second mounted in the boat during construction. In the second photo
you can also see the redundant Racor fuel
filters, the two on the left between the day tank (bottom right of photo) and the engine and the two on the right between the four bunker tanks
and the day tank.
Hope this helps... happy to answer any questions.