New inboard powerboat project

[Flyingkiwi]

Hi,
I am new here and found these forums while researching GoldenMotors.
There seems to be a lot of information on converting displacement and sailing boats to electric but not much on power or planning boats. I am assuming it is because of the weight of the batteries on a smaller boat. Some people have seemed to have done it however so it must be possible.

I need some help in understanding what I need to convert an old Hartley 16 foot plywood powerboat to electric. Here are some specifications on the type of boat I have.
http://www.hartley-boats.com/flare16.html

It currently has an inboard  1960's Ford Mark 1 1300cc petrol engine that is attached to the driveshaft with a clutch. I would look to attach with a direct drive/thrust bearing.

I am looking to see what to power this with and what else I would be needed to convert it.

I still haven't got my head around batteries. The 20Kw DC motor Goldenmotors sells comes in 72 and 96volts. I assume the 96volt one goes faster or goes further??

I have no idea on how many or what size Lifepo4 batteries to get so any guidance there would be appreciated too.

thanks in advance for any assistance.

[Bikemad]

Hi andto the forum,

I suggest you take a look at this thread for some interesting information regarding power and speed.

Inboard Engine Version....will take engines 50 to 250hp.
36hp direct drive gives 15mph (with outdrive 22mph). 185hp will give 42 mph.

I hope you are not looking for too much speed, as according to the above power requirements it is not going to be very quick with a 20kW (~27hp) motor as it is almost half the lowest recommended 50hp. 

Alan
 

[Flyingkiwi]

Thanks Alan
That is one of the things I am trying to find out about what size motor and batteries I need.
I couldn't find a KW to HP conversion but it seems what you are suggesting is that the 20kw Goldenmotor is about 20hp?
I thought I saw that this motor was used in an outboard that stated 50hp but maybe I was wrong?
I will take a look at the tread you sent.
Cheers
Andy

[Bikemad]

745.7 Watts of electrical power is equivalent to 1hp of mechanical horsepower, therefore 20kW is 26.8204hp

Golden Motor advertise a 50hp outboard electric motor but I don't know what size motor is hidden under the cover:



The rated power of the 20kW motor is 20-25kW (26.8-33.5hp), so if it does use the 20kW motor, the Peak power of 50kW would produce around 67hp, but this would only be for short bursts, and it probably wouldn't be able to supply a continuous 50hp for long periods of time.



To produce 50hp at 90% efficiency, it would require 345 Amps @ 120 Volts.

If a 120V 100Ah battery pack were capable of supplying 345 Amps continuously, it would go from being fully charged to fully discharged in just over 17 minutes with a steady 50hp output.

Alan