Glad I found Sailnet
Join Date: Jul 2008
Thanked 51 Times in 50 Posts
Rep Power: 10
I think of it like this: Electric motors run on coal. IMHO, more specifically, electric cars (or boats) get charged somewhere and it costs money to do that charging. If we start plugging our electric drives into shore power, for sure we'll start seeing marinas charge extra for sailboats with electric drives.
Hybrid cars make sense because of all the breaking that they do. Recapturing that energy makes sense. For boats, I think the equivalent is the extra sail power you have up once you reach hull speed. So, for "old shoe" designs that don't really plane, the extra energy is there to recharge batteries from the prop moving through the water. Owners of sailboats with more modern designs, which get extra speed from planing or partially planing, would be less inclined to want hybid drives since it would slow them down. Also remove from this group those "old shoe" designs that are used for living aboard, since they have their own power needs and are less inclined to have the ability to charge engine batteries, especially when (mostly) sitting on the hook.
The other category would be infrequently used sailboat engines that have solar panels to make a dent in the needed charging, and don't go far from home. I picture these as "non-docked solar day sailors", since it's far easier to store energy (motoring distance) as gas or diesel than as batterines -- I'musing 10 miles as the range, pick another number if you want. Since day sailors seem to be the most likely to incorporate modern hull designs that can exceed theoretical hull speed, they are stuck with solar or extension cord charging. If you are at a dock, it's far easier (lighter weight, cheaper) to charge from the power grid (coal) that solar.
So in terms of investment, where it makes sense is with electric drives on sailboats are:
1) old shoe designs that are not at a dock and not live-aboards, capturing prop charging (hybrid drives)
2) any sailboat that doesn't go far from home and is either
2a) infrequently used (solar charging) or
2b) at a dock (coal-based charging) (using edison batteries, see below)
and let's add in this one too...
3) any sailboat that does go far (>10 miles) from home, which has a generator
So I'd invest in making those options viable for people. For #1 that means businesses that retrofit older boats with hybrid systems. For #2 and #3 that means simple, inexpensive, lightweight electric engines and battery systems.
While I'm taking up space on your screen, I'm actually thinking 1) that hybrid sailboats need to use the weight of lead-acid batteries to their advantage with a battery keel. If you are really revamping sailboat designs, use that 8,000 pounds I have as a place to energy storage. That would change the equation a lot by giving you tons of motoring distance.
And 2) that edison battery technology be used along with lead-acid batteries(or any other type of battery that doesn't have many charge-dischage cycles). The edison battery would be used for the first part of discharge and the lead-acid is used for the infrequent final part of discharge. This utilizes the best characteristics of both:
Edison battery: near-infinite charge/discharge cycles, 2% power loss per day, short term overcharging possible in more sophisticated designs.
Lead Acid: very few charge/discharge cycles, 0% power loss per day, no overcharging possible.
All this is IMHO, of course. Hope this helps.
Great minds discuss ideas;
Average minds discuss events;
Small minds discuss people.
The best minds discuss sailing (and a little bit of politics). I don't know why. It's a mystery!