I am building a topic on my Mobile Marine Models tug, based on the Nangee hull, if i mention it on another forum or thread in this forum I have questions to answer so it is just as easy to make a thread about it and then quote the link.
The hull is the Nangee 28 inches by 9 1/8 inches beam, powered by a Bosch electric motor driving a 70mm four bladed screw in a 75mm kort nozzle. The battery pack is two 12volt 3amp/hr batteries in series giving 6 amp/hr.
I started this build about 5 years ago, it is completed, but you allways add bits, or weather a bit so most models remain ongoing.
The boat is single screw, so that I can get a decent battery capacity in her, the single screw probabbly isn't a lot less powerful than twin screw, because I would have had to fit two smaller props and nozzles, and I wouldn't be able to fit two batteries because the motors are quite heavy, but very efficient.