backup power for old sailboat
hello.
i am posting this here first to see how it works, and get comments, if possible..
new to all this, not an engineer, only wish i was - had planned to study for a degree, things did not work out that way, now stuck with a head full of probably impractical ideas, and no way to assess these.
thought i might try here..
my first problem is that i have a old 31 foot glassfiber sailboat hull, 8 foot beam, draws 4 1/2 feet on a concrete ballasted keel..
this is powered by an equally old Yanmar YSE12 inboard diesel engine, originally rated at 12HP. the engine is good shape, however needs care and attention, and i must have a backup plan.
i do not want to carry a petrol/gasoline engine - it is bad enough i must carry diesel. diesel outboards exist but are very heavy and usually very noisy. electric is probably my answer, but i would prefer an hydraulic solution.
my hope would be that i could attach an hydraulic pump to the power take off on my engine, and use this to fill an accumulator or more. the idea being that i could then use this accumulated power to run an hydraulic outboard leg for a given distance, should i need power in an emergency, and also for maneuvering in tight spots.
given that i can find or construct an hydraulic outboard leg to suit, i am told that about 2Kw average is what i will need to drive my boat effectively.
is there a way that i might calculate, on the basis of Kw consumption, what sort of range i might expect to get from a given accumulator?
i understand that a lot will depend on how wide and how long the hydraulic lines are, as well as the efficiency of the motor - at this point i just want to get an idea how impractical this plan probably is, in terms of how large the necessary accumlator(s) would be, to provide any sort of useful range.
could anyone suggest where i might find these answers, and/or if this has been tried before?