GoldenMotor.com Forum

General Category => Electric Boat Conversions => Topic started by: Flyingkiwi on July 13, 2017, 11:09:31 AM

Title: New inboard powerboat project
Post by: Flyingkiwi on July 13, 2017, 11:09:31 AM

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.

Title: Re: New inboard powerboat project
Post by: Bikemad on July 13, 2017, 11:31:01 AM

Hi and(https://i.imgur.com/evDSMvT.png)to the forum,

I suggest you take a look at this thread (https://goldenmotor.com/SMF/index.php?topic=6127.0) for some interesting information regarding power and speed.

Quote

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
 

Title: Re: New inboard powerboat project
Post by: Flyingkiwi on July 16, 2017, 09:39:55 PM

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

Title: Re: New inboard powerboat project
Post by: Bikemad on July 16, 2017, 11:22:21 PM

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:

(https://sc01.alicdn.com/kf/HTB1B4J5MpXXXXc_XpXXq6xXFXXXm/50HP-electric-outboard-motor.jpg)

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.

(https://sc01.alicdn.com/kf/HTB1tjh4MXXXXXXvXFXXq6xXFXXX7/200049500/HTB1tjh4MXXXXXXvXFXXq6xXFXXX7.jpg)

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