electric c-dory and speed with kickers

[croakz]

OK you buy the 48 volt 100 amp hour battery. How are you going to recharge it when cruising? I have not owned an e-Propulsion Spirit 1.0 and don't know if it can be recharged from 12 volts, but the Torqeedo can be, and it was often recharged when running the outboard as we recharged the 200 amp hours of Battle Born house battery.

I have a Victron 12/12 18A DC to DC smart charger going to a bank of 2 x 100AH lifepo4s now. I use those to charge an Ecoflow Delta Mini via a 12v to 24v step up.

If I added 48V battery, I'd probably just get a 48V AC charger and plug it into my Ecoflow to charge on the water. And then I could also that AC charger when shore power is available. Charger loss efficiencies aside, it'd be a simple solution.

I also have a 12V charger for my ePropulsion, but I wanted the ability to use it longer than the 25Ah battery that comes with it. Thus the larger 48V battery. I don't think you can run a Torqueedo or ePropulsion off straight 12V.

 

[Roamad]

I recently explored this quite a bit while working on repowering my 16 CD. The most promising option seemed to be a company in Seattle called Pure Watercraft. They make a very sleek 50hp-equivalent electric outboard and their people were very helpful in walking me through the potential. (They recently signed a partnership deal with General Motors — imagine that!)

Anyway, much of their testing was done with boats similar to mine in length and weight. They estimated I could see 7 hours of run time at 4-6 mph, with enough top end to reach planing speed (resulting in significantly less run time, of course). The weight of the motor/battery package is very similar to a 50hp gas outboard & fuel tank.

The total package would have cost near $20k, however. So I ended up going with a used 4-stroke EFI motor, which set me back about $5,500 installed.

I know the OP asked about using a kicker-size electric outboard. But I thought this was useful info for comparison anyway. Here’s a link to the Pure Watercraft motor:

https://www.purewatercraft.com/product/pure-outboard/

 

[ssobol]

… or any possibilities of fire. ...

Plenty of examples of electric cars on fire. Just search YouTube.

Chevy says not to park your new Bolt in your garage because of the fire risk.

 

[LesR]

Here's the boat we saw in Auke Bay last July, which appears to be a practical (albeit slow) electric cruiser. They made the trip from Bellingham to Ketchikan in 20 days, roughly double the time it took us. Alex told me they could run continuously during the day at 5 knots using power from their solar panels. Faster than that or in low light conditions ate into their available battery power.




Link to Devlin's site that includes more detail.
https://devlinboat.com/solar-sal-27-the-latest-launch-from-our-shop/

 

[thataway]

I have a Victron 12/12 18A DC to DC smart charger going to a bank of 2 x 100AH lifepo4s now. I use those to charge an Ecoflow Delta Mini via a 12v to 24v step up.

If I added 48V battery, I'd probably just get a 48V AC charger and plug it into my Ecoflow to charge on the water. And then I could also that AC charger when shore power is available. Charger loss efficiencies aside, it'd be a simple solution.

I use a Sterling 30 AM B to B charger, and that is just enough usually to keep up with two 100 amp hour batteries use for chest freezer/refrigerator. You will have to run a very long time with the Victron (I have the Orion in my second portable setup I use for the SUV refer, so I know what its characteristics are.) You are not going to be keeping up unless there is minimal use of the 48 volt power supply. There is going to be a moderate amount of loss with use of chargers, inverters, etc. You will rapidly deplete the "EcoFlow DELTA Mini's" battery with the 48 volt charger--almost like perpetual motion...the numbers just don't add up.

I also have a 12V charger for my ePropulsion, but I wanted the ability to use it longer than the 25Ah battery that comes with it. Thus the larger 48V battery. I don't think you can run a Torqueedo or ePropulsion off straight 12V.

The Torqeedo charges on 12 volts--and can be charged by either another power source, including solar when running. That may not be "running" off 12 volts, but 12 volt power source is providing the charging to keep the battery topped off. Torqeedo battery nominal voltage is 29.6 volts. Early on Torqeedo Australia did an open ocean run with the Torqeedo (I believe the 1103) of 30 miles. They had solar panels on a Bimini type of structure. During the height of the day, the net draw was zero from the battery and as I recollect they were doing about 2.5 knots...

From the Torqeedo manual:

According to section 6.4.2 on page 79 of the Travel outboard User Manual,
"Charge using a DC power supply in the range of 9.5 V to 50 V.
The DC power supply must be able to provide at least 4 A.
Use the Torqeedo 12/24 V charging cable (item number 1128-00) for charging."

"The battery can be charged during use (charge and discharge at the same time). The power display shows only the power being drawn from the battery in this case. If the charging current is greater than the current drawn by the motor, the power display shows 0 W and the battery is being charged. The charge status display takes into account the charging current as well as the current drawn by the motor."

.

 

[croakz]

You are not going to be keeping up unless there is minimal use of the 48 volt power supply. There is going to be a moderate amount of loss with use of chargers, inverters, etc. You will rapidly deplete the "EcoFlow DELTA Mini's" battery with the 48 volt charger--almost like perpetual motion...the numbers just don't add up.

Hi Bob,
My goal is not to keep up, it’s to last longer than the battery that comes with it. I could get a spare ePropulsion battery, but an external lifepo4 seemed more versatile. I guess I could do 12v @ 400ah vs 48v @ 100ah, but 48v is native to the ePropulsion. It’s not dissimilar to you using a torqeedo and charging over 12v, it’d not going to keep up either. At least not at 1000 watts. But it prolongs it.

- tom

 

[thataway]

Yandina makes the "Trollbridge" battery charger for 24 and 36 volts. She might give you advice, find a way to modify one of the stock units or make a 48 volt one for you. I suspect that there are a number of other 48 volt applications where this would be utilized, if one wanted to charge a group of batteries in parallel, and use in series.

I am not certain what year Honda 90 you have, but those prior to 2006/07 were only 17 amps 12 volt output. A certain amount is necessary for the engine and boat's electronics...not a lot left over for battery charging..

 

[South of Heaven]

Good luck OP. I would say the CD hull would not be ideal for that. It's a planing hull.

I guess maybe on a quiet, inland canal it could work with winds of less than 5 knots.

 

[hardee]

Bob, understood re wanting a longer narrower hull. Are there any specific hulls out there you think would make a good base for this kind of project? Something like a modern Monterey Clipper? (Is anyone building those?)

Check out the "Allweather26" for a canoe hull.

Allweatherboats.com

Harvey
SleepyC :moon

 

[hardee]

Bob, understood re wanting a longer narrower hull. Are there any specific hulls out there you think would make a good base for this kind of project? Something like a modern Monterey Clipper? (Is anyone building those?)

Check out the "Allweather26" for a canoe hull.

Allweatherboats.com

Harvey
SleepyC :moon

 

[Moxieabs]

Look at the electric outboards of various sizes by "Flux"

 

[ChrisD]

If you want to hit hull speed in a CD22, with a little extra power to handle a heavily loaded boat or wind/tides/currents, I would suggest no less than 8 hp or the electric equivalent.

A 9.9 kicker pushes my 22 Angler along very happily at a bit over 6 mph, while burning slightly less than 1 gallon per hour.

This is trawler-class economy, and if you close the cabin door the lapping of water at the bow is the loudest thing you hear. An electric would be even quieter, so I definitely see the appeal of electric propulsion.

You would probably be fine with a smaller electric motor under perfect conditions. But if you’ve got a heavily-loaded boat you’ll be making a deeper hole in the water and it will take more power to move it at hull speed.

If you’re bucking a strong tide or current you’ll get nowhere if your speed through the water is only 4 mph.

And if the wind starts pushing you around, you’ll need a lot more power to counteract it. CD-22s are light boats with a lot of sail area, abd many of them have full cockpit canvas too.

Installing adequate battery capacity for an electric motor with this thrust is a challenge with current technology. A small portable fuel tank gives hours of cruising and dozens of miles of range with a small 4-stroke outboard; this would be hard to duplicate with battery power right now.

 

[robhwa]

Actually, it's possible to make your electric motor able to run for long periods, though the solution has caveats. In the hot, humid conditions of the SE in summer, it's difficult to sleep without air conditioning, and old age isn't making it any easier. I carry a Honda 2200 to run the AC. With the addition of a new inverter/charger my CD22 can maintain the 1500 watts required to drive 160 lb of thrust of two Minn Kota trolling motors (80 lb each), one bow-mounted and one mounted above the anti-ventilation plate of the main motor. It can do this while recharging the 230 AH 24 VDC battery used to run the motors. Max speed is about 4 statute MPH with both, 3 MPH with either one alone, depending on loading. The main issue is the bow motor coming out of the water occasionally during rough conditions.

 

[Tom Hruby]

Sorry I missed out on this thread. I do have an electric 22' C-dory cruiser and now have three years of data on it. Check out some of my posts for the data and information I have collected. In general, my cruising weight is 4000 lbs. At that weight I need 6kW to get to hull speed, but only 2kW to reach 75% hull speed (about 5.1 mph). I have posted my power vs. speed curve in my album WATT NOW. I have 20kWh of batteries stored in the space for the fuel tanks; so that gives me about 45-50 miles per charge at 5.1mph. I have two 3.0 kW Epropulsion outboards.
From the info I have seen posted on C-brats, folks have commented that the 22' C-dory gets on a plane at about 11-12 mph. Using the equations in Dave Gerr's Propeller Handbook for both displacement hulls and planing hulls, I estimate that it will take about 12kW to get my boat on a plane. The speed vs. power curve I have measured for my boat is almost a perfect fit for the power curve I can calculate for displacement hulls using Gerr's equations.

Previous to my purchasing the C-dory, I cruised in 26' St. Pierre Dories for 15 years using the most powerful trolling motors available (first the Motor Guide 106, and then the Minn Kota 112). The controllers for both overheated when run at higher power (2/3 or more, of maximum stated current). The Motor Guides were a problem because the PWM controller was with the motor in the water, and I had throttle down or stop completely until it cooled. In the Minn Kota's the controller was in the throttle head so I drilled holes into the cover and added small computer fans (12V). That let me cruise at about 80% of capacity.

 

[thataway]

There are newer batteries on the horizon which will be higher energy density, work in cold weather and charge faster. So far the LiFeP04 batterie is still the best for small boat operations. I have been doing an experiment with cheap (about $150 each for 100 amp hr battery) 600 amp hour bank--figure on at least 400 amp hour usable. and solar Panels of 1200 watts total. This is to be used at home in case all power is down (we have a 18KW natural gas back up generator) in the relatively isolated area where our home is located. The total cost is in the $1500 range and would power a refrigerator, a freezer as well as small 12 volt Led light fixtures. It has a 1500 watt inverter, to be used during the day to run appliances as needed. There is enough extra on a good sunny day, to charge batteries, such as tools, flashlights and back up batteries for my internet modem etc. We also have a well into the main aquifer, and a 12 volt pump to fill water containers if necessary.

I have a separate package of a 100 amp hour battery, Orion charger off the SUV battery, Using a group 31 battery case to hold the battery, inverter and a b to b charger to power a 12 volt 1.5 cu foot chest ref/freezer to bring frozen food home from the store, if we had other chores to do, or stop and visit with friends. This is normaly charged with a 10 amp 120 volt mains power at night. In case of loss of mains power, the solar panel setup will work to power the above household appliances

Sodium batteries, and silicon enhanced FePO4, and other solid state technologies.

 

[colbysmith]

I had a Tohatsu 6hp kicker on my 22. Even running heavy, it could push me at hull speed of about 5-6mph. This was also in 1 ft of chop. I had used it in some larger 2 foot waves while trolling as well. Until you get enough HP to get up on plane, a larger kicker is not going to gain you any more speed. It's my understanding the length of the boat predicates hull speed, not the weight of the boat. (I accept a heavier boat will have a little more draft, very slightly increasing the hull length at the water line....)