What experiences do you have with electric propulsion for your tenders? Do you have personal experience with any of the following, or any other? epropulsion aquawatt torqueedo ... Many thanks!
Elco electric outboards might be an option you could consider. I've begun to consider options for a console dinghy, approx 12' or so, with 15-20 hp propulsion. From cursory analysis, Elco's outboards are lighter weight (than gas), but then traditional batteries are heavier, and LiFePO4 batteries are more expensive (conceptually buying all of your lifetime "gas" upfront). I haven't spreadsheeted the actual comparison figures, though. -Chris
15 years ago I wrote a viability thesis on electric outboards for Yamaha. I’m unsure of the development status, but I expect an offering will be coming to market.
I've used the Torqueedo and didn't like it at all. A new brand has come to market and I took it for a test, the Epropulsion Spirit. It works just like those 2.5 or 3.3hp dinghy outboards everyone has used at some point. The Navy 6 is about a 9.9hp. Very neat package. https://www.epropulsion.com/spirit-1/
As a huge Yamaha fan over the years, I'd love to believe so, but right now I'm seeing so little development out of Yamaha I'd be very surprised. I always argued Yamaha vs. Mercury and recently I've had to concede. I don't know what is going on right now with them. Mercury now has 500 and 600 hp, they have diesel outboards, they have jet outboards and they have a propane outboard. I would feel certain they're experimenting with electric or that they will buy an electric line to expand. I think Yamaha is hibernating or something. I've even seen it in their parts and accessories deliveries with a friend trying to get a wiring harness. Anyone not looking at electric and experimenting with it will regret not doing so. I think back to when people inside Barnes and Noble suggested online selling and then Amazon hit and the company stance in B&N was it would never work, people would never buy books online. I'm pleasantly amazed that not a single auto manufacturer has ignored electric. I think for outboards, the first thing we'll see is the death of gas outboards under 10 hp and I think that's sooner than most anticipate.
I am not so sure, I think a big percentage of small outboards are used where you have no electricity today..?
I've used a Minn-Kota and Newport Vessels on a 10' Livingston. I liked either of them better than the trouble of a gas outboard. The Newport Vessels outboard is 55# thrust and I guess it moves the boat at about 7-8 knots. I mostly use the boat around my dock and usually run flat out only slowing to dock. The Minn-Kota was knocked off the transom by a big wave in the night, thought it was stolen. 2 years later when the river was low, saw it sticking out of the mud. Washed the silt out, dried and it still runs fine. If you don't run the battery too low before charging, it lasts years. Current battery is 8 years old.
Well, in my case it's the other way around. On the lake where we live gas engines are not allowed! But I do need the boat to get to the house... Reg batteries: would you rather use 2 batteries or one with larger capacity (e.g. epropulsion 2xE40 or 1xE80)?
We have probably more than 2 dozen Torqeedo 1103 C electrical outboard engines plus a spare battery for each outboard on our boats. But not for professional use, only as propulsion for the toys for the kids, my grand children and their friends. They are used for small tenders, mostly Honwave 285 fully inflatable dinghies or for little sailing dinghies and Hobby Cats. They work flawless, require no installation on the dinghy, the battery is on the outboard and can be exchanged in seconds, they are waterproof, if submerged, can be lifted by a kid (only 25 lbs) and spare parts are cheep (except the battery ). A new prop for example costs about 35 $. And with its power, they are below the requirement for a drivers license and can therefore be used by the kids regardless of age. Again, a nice toy and as a dinghy propulsion for smaller boats, pretty much perfect but not for professional tender propulsion and for every day prolonged use. For this purpose, I would prefer internal combustion engines for range, performance and independence. Here we are using only diesel outboards, as we do not want gasoline fuel at all on our boats. But they are only used by licensed drivers. I have one boat, a 39 ft wooden replica of a historical launch with a 30 KW, 48 volt DC, electric inboard propulsion with shaft and conventional prop for use on the Binnenalster (the intown water ways in Hamburg), where combustion engines are forbidden for private boats. But this boat is purely for coffee cruising during nice weather with guests and family on a sunny afternoon. The battery pack allows cruising at app. 5 kts for 5 to 6 hours with 12 people on board. The batteries are Victron 2 volt VRLA (Valve Regulated Lead Acid) batteries (forglift batteries) mounted horizontally under the floor boards and switched to an high capacity 48 Volt battery array. They have a life span of up to 20 years and are very reliable. Pretty heavy set of batteries but very usefull in this case, for the stability of the boat. To bad, only the professional excursion boats in Hamburg are allowed to have combustion engines, some of them still have steam engines! Electric cars, boats and planes may be the future but with todays battery technology are only usable for special purposes and when asked for by enviromental reasons (Underground mining vehicles for example ) . These high performance LiPo batteries are far to expensive and far to prone to failure at this stage of developement. Will say, for an electric outboard, just keep it simple and easy on Your wallet. Just my two (Euro) cents HTMO9