Randy, Mark Stafford again. To make headway against wind and waves, you need a big propeller. If your old 9hp ICE could drive you 6knots in calm water, an Etek, Mars, Agni, etc. electric motor should be fine. Use a reduction belt (or direct drive with auxiliary cooling) system. If you can fit one, a 24" two bladed prop could hide behind the keel to minimize drag while under sail, yet provide the necessary bite to combat seas. A 20" three or four bladed prop should also do the trick while additionally providing minimal regeneration battery charging under sail (comparable to solar in terms of minor yet constant benefit). With regeneration, you might lose 10% in speed for a given sail area, but if you are already at hull speed, you'd never know (130% sail power still produces only 100% speed, minus 10% for regen leaves 120% sail power, which is still only 100% hull speed.)
Anyone out there with hard numbers on props for a Cal29? Or big prop regeneration charging? I suspect big ducted props (like the new tugboats) would be best, though I've no data.
Mark Stafford
--- In electricboats@
>
>
> Hi Keith.
>
> Thanks for the interest in my problem.
>
> First we sail mostly in our Home port of Sandusky Bay in Ohio on Lake
> Erie, and around the islands. It's great to be able to go out in almost
> any weather condition and not have to face 8-10' short waves if you
> don't want to. Although I do that sometimes as well when it's warm and
> I want a change of pace.
>
> My comment on the under power is more concerned with head winds and
> waves. A short story, We went to Put in Bay for the weekend. took 2
> hours to get there. Great Sail at hull speed. Wanted to get back the
> next moring before the wind really picked up to 35. Reefed the main,
> unrolled a little Jenny and off we went. Great sail again till I had to
> turn more south and had to tight haul into the waves and wind. (It took
> us 8 hours to get back, not fun).
>
> Started motor went about 30 mins into the wind, only problem was we
> could only go about .5 KPH over water speed. Then beacuse of age of
> boat and tank and engine, the engine died from a plugged fuel filter. I
> Guess the rust in the tank wanted out of the boat as much as we did.
> ;-).
>
> We get 6 knots at 2500 PRM in flat water which is great. Don't really
> need much more than that except in certain conditions (you know the
> stupid one like I described above).
>
> We rarely go through more than a few gallons of fuel during the summer.
> It's mostly used for going to the weekly race course or in/out of the
> marina.
>
> Every place I have stayed has shore power, But I know I will need some
> other way of charging the batteries. I plan to do the solar panel but
> that won't be enough for long trip recharges. I also think that a small
> Honda generator would suffice for power for the chraging system as well
> as house needs if we are not close to shore power.
>
> As far as range. We have always sailed in the Bay/Islands but we now
> want to go cruising with the cruising fleet at SSC. I am thinking that
> 4 hours of running at dead calm could get us to almost any port up or
> down the shoreline in Lake Erie. We are not fans of motoring so I don't
> see us leaving a dockage without good wind forecasts.
>
> As far as your comment about repacing the W-B, Everyone I have contacted
> here has quoted in the 5500-10,000$
> That's why I am looking seriously at the electric option.
>
> Randy
>
> CAL 2-29, Ariel, Sandusky Sailing Club
>
> Sandusky, Ohio
>
>
> --- In electricboats@
> <aweekdaysailor@
> >
> > Hi Randy,
> >
> > Welcome! I have a boat very similar to yours that I converted to
> electric a while back. When you say the Westerbeke is underpowered - can
> you elaborate? What kind of speed do you get at full-throttle? At
> cruising-throttle? And if you know the size and pitch of your prop that
> will also help.
> >
> > Also please describe the sailing conditions (typical, as well as
> worst-case) - currents, wind-patterns, etc.
> >
> > We also need some sense of how much speed and range you expect
> (without auxillary power like a genset). On your weekend trips - will
> you have access to shorepower?
> >
> > The Thunderstruck kit is not intended for direct-drive - they just
> leave the mounting as an exercise for the reader :) Note that there are
> vendors with more turnkey systems, but are priced accordingly. This
> system will typically need a 2:1 reduction.
> >
> > Best-case - you are looking at about $3K for a setup
> (motor/controller, batteries, cables, trays, meters, transmission, etc)
> including a lot of DIY effort. You probably already know you can replace
> your w-b for about the same or less.
> >
> > The pros and cons are going to depend a lot on you and your
> expectations. Your inclination to being fastidious (I am not) and
> detailed oriented (ditto) will mean a lot. Mechanical/electric
> also count (much to my dismay).
> >
> > It is helpful to put electric in context - think about all the trips
> you have taken - now imagine you started with 1 gallon of fuel and think
> about how the trip would have changed.
> >
> > Regards,
> >
> > -Keith
> > e-S/V "Aja" - 1978 Hunter 30
> > San Francisco
> >
> > --- In electricboats@
> > >
> > > I have a westerbeake 1 lung 9hp diesel that is woefully
> underpowered. This winter the JB Weld that was dealing a cracked block
> in the water jacket sprung a leak. It is now time to take a serius look
> at an inexpensive EV system.
> > >
> > > I looked at the Thuderstruck page and it seems to be the cheapest
> and fairly simple to install.
> > >
> > > We pretty much do day sailing with some weekends in the plans.
> > >
> > > It also looks a\like a direct drive system rather than a belt
> system.
> > >
> > > Can anyone enlighten me on the pros and cons?
> > >
> > > Thanks
> > > Randy
> > >
> >
>
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