So I've recently become the happy owner of a small 4 ton 1976 British catamaran. It currently has twin diesels, one of which is in a bit of disrepair. Being a huge fan of electric motors I think this is the perfect opportunity to go electric, or rather hybrid considering I'm keeping one diesel.
Now the boat is currently shaft drive, so I either bolt a motor directly onto the shaft, or close up the holes and fit an electric outboard. I'm torn between the two options.
I'll be running a 48v280AH lifepo4 bank, with at least 1200w of solar for charging. I'll mostly use power very sparingly, long slow runs are where e-boats excel, so it won't often happen that I'm pushing more than 3kw into it.
In terms of power I was initially looking at the e-propulsion navy 6.0, but it seems to be much simpler if I just keep the shaft drive and put the motor inboard. I know quite a few boats are using the 10kW BLDC motor quite happily, though I've heard they get pretty hot. Also the RPM of the motor is much too high for a sailboat which needs a big slow spinning prop.
The solution I'm thinking of is instead of fitting a reduction drive along with the complications that come along with it, would be to rather order the 96v or 120v motor, and then run it at 48v. The lower kv of the high voltage motor will hopefully mean I still have all the torque I need, without trying to spin the prop too fast and overheating the motor.
Any flaws to my thinking here? What would you do?
Now the boat is currently shaft drive, so I either bolt a motor directly onto the shaft, or close up the holes and fit an electric outboard. I'm torn between the two options.
I'll be running a 48v280AH lifepo4 bank, with at least 1200w of solar for charging. I'll mostly use power very sparingly, long slow runs are where e-boats excel, so it won't often happen that I'm pushing more than 3kw into it.
In terms of power I was initially looking at the e-propulsion navy 6.0, but it seems to be much simpler if I just keep the shaft drive and put the motor inboard. I know quite a few boats are using the 10kW BLDC motor quite happily, though I've heard they get pretty hot. Also the RPM of the motor is much too high for a sailboat which needs a big slow spinning prop.
The solution I'm thinking of is instead of fitting a reduction drive along with the complications that come along with it, would be to rather order the 96v or 120v motor, and then run it at 48v. The lower kv of the high voltage motor will hopefully mean I still have all the torque I need, without trying to spin the prop too fast and overheating the motor.
Any flaws to my thinking here? What would you do?
