Electric outboard or pod drive?

We have a Parker 235 with a 5hp outboard, and we would like to move to an electric power system.

The outboard sits in the engine well that you can see on the attached photograph.

Despite the cost, our reasons for wanting to go electric are as follows:

Quieter - We have decent Tohatsu 4-stroke, but it still too noisy to talk over and motoring is not the pleasant experience that make boating worth it.
Safety- We have two young boys, and there is only me who can start the engine
Space - An electric outboard would be smaller, leaving more space in the cockpit.

With the last point in mind, would it be worth moving to a pod drive instead of an electric outboard? I am a mechanical engineer, so could design a system to mount the pod on a plate so it can lift out of the water, or so that I can remove it completely.

The engine well could also have a full cover-plate so there is more floor space.

The outboard option can be turned so that there is extra manoeuvrability at low speeds, but is this worth the loss in cockpit space? I could possibly even design a linkage so the pod turns with the tiller.

Any thoughts and experiences with either solution would be appreciated.

Sam

 

I always recommend electric outboards over POD motors for some of the same reasons I would recommend an ICE outboard over an inboard motor, with the main difference being that the finishes and materials of most POD motors do not hold up well living full time in water.

An electric outboard can also be easily shared between boats, stowed away easily without worry of fumes or fuel leaks, swapped, serviced while removed from the boat, etc..

If you want a bit of both in operation, consider an electric Outboard paired with a remote helm throttle control station like EPropulsion and Torqeedo offer for use.

That way you can ditch the tiller and twist throttle, fix the outboard straight ahead and use your boats steering and place the throttle control wherever you’d like.

Most are wireless these days which makes installation a breeze.

Another cool option is the ability to detach the battery from some models of electric outboards and use an extended cable allowing you to remove weight and bulk of the motor from your transom and place the battery is a more convenient spot.

And some have the ability to take Solar charging while being used to either offset your use while underway, or to recharge and top off your battery so you don’t need to charge at home or at the dock.

Also one of the best things about electric propulsion in my opinion (in addition to it being quiet and fine free) is there is no gear change lever, so you can easily transition between forward an reverse propulsion and since electric motors don’t idle, you have very precise control all the way down to zero RPM without fear and worry of the more dying at the worst possible moment.

 

Thanks for the comments.

If we went for a pod drive, I would design a system of lifting the drive out of the water to reduce fouling, and for maintenance.

I did think about the remote throttle option, but a main point in favour of the outboard is the low speed steering control from being able to direct the propeller thrust.

 

Certainly nothing wrong with adapting a POD motor in the way you describe, I just always try to talk people out of drilling holes in the bottom of a boat and introducing a potential water ingress and/or hull issue.

If you decide to go the traditional outboard route, and you plan to kick and maneuver the transom using the tiller and throttle, then definitely make sure you securely mount the clamp.

I like to drill countersunk holes for the clamp screws once I have settled on a position just to keep it from twisting off under side thrust and hard lock.

One idea since you have some engineering skills would be to use a steering drag link as you mentioned then mount a remote potentiometer on your tiller so you can steer and control the throttle from your boats existing tiller.

 

This is a slow burning project, but I have some ideas. This shows an ePropulsion Navy 3 sitting in the engine well.

https://photos.google.com/photo/AF1QipMYj37SyBS5sJcGB5sX1LvMLGA3m0rqJwl3Kste

 

What HP is the outboard. You will need to match the electric motor power to it to get the same performance.

 

The current outboard is a 6hp 4-stroke Tohatsu, so 4.4kW. I think a 3kW direct drive electric pod or outboard should do the job. I doubt there is much point increasing the power beyond this.

 

A big advantage of a pod over an electric outboard is that it would free up a lot of space in the cockpit and would also mean that I can cover up the engine well.

The electric outboard is easier to fit and it has its own tiller, which is good for low speed manoeuvring. However, it is easy to steal, so we should probably remove it when we leave the boat. However at 25kg+, it is a big lump to stick in a canoe or dinghy to bring home after each trip, especially if we are carrying the battery too. I'd be interested to hear how people use outboards on smallish (23ft) boats. Do you carry it home after each trip? Are you on a swinging mooring? Do you leave it inside the boat and risk a break-in to get to the motor?

The pod drive requires some more involved engineering, but maybe it is worth the extra work.

 

Most people leave the motor mounted on the boat. Usually a padlock or other safety measure is added.

 

There are some new models coming out that are less powerful than the Navy but more than the Spirit with integrated battery which is likely detachable making it easier to transport and charge separately, possibly even remotely locate-able as with their Spirit models, and with a separate transom clamp like their smallest ELite that stays clamped on the boat allowing for the motor to be dropped on it in an effort to reduce weight and size of the motor when removing and transporting.

I don’t know what the conditions are like in the waters you use your boat in but it’s possible if you are only using the motor for getting in and out of a slip/marina or putting around when you’re feeling too lazy to raise the sails, etc.., that a smaller motor with a short Boost Mode feature might work well for you if lightweight, compact and transportable are a top priority.

To give you an idea of what a 500W motor can do running on 250W, here is EPropulsions ELite pushing my 25’ x 18’ wide Trimaran up river and around my mooring field.

The motor is left fixed and I use my rudder and tiller to steer.

I also use it to get on and off my ball and use the Boost Mode feature occasionally when needed when I am pushing into stronger wind when approaching my mooring.

The electric motor makes for a very controlled, slow smooth and steady approach with small lightweight boats where the idle speed of an ICE outboard might be a bit too fast, and since you can throttle down to a few RPM and kick it right into reverse without changing gears and have ample torque, there’s a lot less drama and stress of having to grab the ball or pickup line.

And the same goes for dock or shore approaches.