I am building a power trimaran
based on two 30 hp outboards. however they only put out 15 amp each when underway.
I am putting in 800 amp hours of AGM
batteries which charge at a much higher rate than wet cell.
I am planning to use all 240volt appliances
(mains current in Australia) with a 2500amp inverter
. A 9,000btu airconditioner will be used at night. which is far far cheaper than 12 volt systems and I am happy to replace them all in two - three years. I save $10,000 by using this system.
I dont believe solar
or wind is very efficent if you take into account the extremely high capital cost and variability of use. $3,000 of capital cost goes a long way with running a Honda
at 1/2 gallon of gasoline per hour.
I plan to have a 13 hp Honda auxillary but I don't want that running all day either. So the more I can pump out of the alternators the better, even if it is only up to 80-90 % of battery capacity (smart charger)
The honda will also run a Cat high pressure pump for desalination.
I do like the idea of having two alternators which I can buy (new) for $150.00 each whereas a 180 amp would cost be over $1,000.00.
A 13hp can easily run two 100amp alternators.