What about coming at it from a new angle, albeit an angle that has been explored before?
I was searching and searching for ideas regarding powering the A/C (one unit at a time) and for managing power in general aboard the boat.
I noticed that you can purchase Balmar
alternators that will put out 210A at 12V if spun at 6000RPM. Inverted to 120V, this still gives a whopping 20A service
. Given that today's inverters can run at 5KW with peak outputs in the 9KW range, I could CERTAINLY run one single
AC off this system from time to time. (Never off the batteries alone, of course, only while the Balmer alternator
The added bonus is that there would be a ridiculous amount of DC power available to the boat while running in this mode.
There is a 2nd mode:
Given that this is a DC charging
system, I could spin the Balmer at a substantially lower RPM
when generating DC power to charge the battery
bank when there is no AC on. This would eliminate the question of the Alder Barbour fridge requiring a lot of time on an AC genset to charge. It would allow all of my DC computer equipment
to have plenty of power, and have the battery
bank act as a power "well" for the entire boat.
Any reason this wouldn't work? I am looking at finding a small, air-cooled diesel
to spin the Balmer alternator
. I could rev it up to about 3600 RPM
when running the AC through the inverter
(at a 2:1 ratio, so the Balmer spins at 7200). Then, when I need a more normal amount of DC power, I have a nice, efficient, 1800 RPM DC diesel
The only issue... need to find those small air cooled diesels. Depending on the price
for one, and the price
for the inverter
, this could be similar in cost to a 6KW AC genset.
Added Bonus: Engine
will last longer running at a slower speed for normal charging
, modern inverters can handle the peaks the AC throws at them, batteries will remain charged well at all times, and best of all... individual components can be replaced if they break.
Does anyone see drawbacks to this general approach? Cost might be a factor, but any other drawbacks?