Next message: Jim Burgoyne: "[world-cruising] Re: engineless"
--- In , "barry Brazier"
<b dot w dot brazier at b dot dot dot > wrote:
> At 5 knt. I think it is easy to produce a prop shaft speed of >500
>rpm using an typical 18 x 10 prop. That could produce a alternator
>speed of >1500 rpm using a 3:1 belt dive and produce 15 amps at 12
volt.
Well, you're absolutely right. I just hadn't imagined dragging
around an 18" 3 bladed (it would have to be mounted in reverse to
get that type of work/efficiency out of it) on a vancouver 27.
I've experimented with my Rasmus 35 that has a 3 blade, 15"
MaxProp. I can lock the prop in reverse. With it just free
wheeling, at 5knt, it might as well be a drogue. Of course, the
advantage of a feathering prop is that one can choose not to regen
in low wind conditions. In my case, the verdict is out on whether I
regen this way or not. As I'm currently doing a refit, the time is
coming to fish or cut bait.
BTW, I will be pleased as punch to produce 5 amps; that works out to
120 amp/hrs per day and is, to my thinking, a huge benefit.
eric S/V Nebaras
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