Hybrid HT

I've been procrastinating on the re-power of my HT 27 for over a year now. I think I have made up my mind and will begin the installation soon. I’m sure I said that before too.

Motors: Two torqeedo cruse motors at 2Kw each
According to torqeedo’s tech support these motors should push her at 6kts. I have checked this number against independent spread sheet calculations and it is close. On torqeedo: It took me some time to get an answer from them. After three email attempts with no reply, I called Germany and got their US office number … After I got an answer in my second email I’ve asked about regen etc. but no reply again. Let’s hope their motors are a lot better than their support.

Engine: I got a great deal on a D722 Kubota diesel 20HP engine with 5 hrs on it for $1.5K wanted something slightly smaller but the deal was way too good to pass up. New they are over $3.4K

APU Kit: Am working with Ecycle to get their APU kit installed on the Kubota engine which should give me more than enough power, 9Kw at reasonable RPM. Although they are trying to get me to go through a dealer, and none of the dealers on the west coast (US) has heard of them, so it’s causing some delays.

The bonus of having this additional/excess generator power means I can add an additional torqeedo if necessary if the two don’t live up to the numbers. And run the motors flat out while charging the batteries flat out.

For batteries I'm looking at thunder-sky 8 X 200AH 2.5V-4.25V L-ion basically 200 amp hours at 24-36VDC. For $2.5K EX Works (china). So probably over $3K with duties, shipping etc. Their normal charge rate is ½ capacity (0.5CA) i.e. 3.6Kw. Total Weight will be 60Kg.
Comparing this to the popular T105 lead acid you would need around 10 T105’s with 10 weighing in at 280Kg, charge time would be unacceptable but the price would be $1.3K, less than half.

The motors run at a max of 4Kw and the batteries will take 3.6Kw charge, this way I think I can run on batteries for around an hour and then run the engine which will run the motors and charge the batteries back in just over an hour. So an hour on and an hour off.

It's going to cost me over $10K with spares and batteries.
I have a sillett sail drive leg, thanks DavidH, that I will install later to turn this into a parallel hybrid.

There is still much to work out re. outboard brackets, charger/s, marinization and installation of the D722

Any comments, feedback will be appreciated.