[electricboats] Electric motor size for 48' cat

Hello all, complete newb here, so I'll start with a very basic newb question.  First, the setup - we have a 1992 Privilege 482 catamaran with one dead diesel and the other still the original Volvo, but running well.  Light displacement about 26,000 lbs., as loaded probably close to 30,000 lbs.  With 2 old Volvo MD22's (50hp each) motoring speed was typically 7 knots at about 2000 rpm.  With just the one motor we do about 5 - 5.5.  We are full time long range cruisers so we're either at anchor or passage making - most hops are a full day, with many being multiple day passages.  We also have a 6kw Northern Lights generator which performs well and currently only about 400 watts of useable solar (this will be upgraded soon to at least 1000, possibly up to about 1600).  Our house bank is 900 amp hours of lithium, only 8 months old, but they're x3 12v 300 amp hour units, so not great for building a "master bank" for the motors from.  This being the case, if we went electric, I would be inclined to set up the motor(s) with their own unique bank and charging system(s) and keep the house as it is, controlling what gets charged when manually.

With our port motor locked up AND 30 years old, I'm very seriously considering an electric motor conversion as opposed to a rebuild (as well as several pricey parts I know it will need).  I really like what Thunderstruck Motors has to offer, but just with a very basic consultation, they're suggesting the 24kw motor kits (we would actually just do the one side at first, operating with one diesel and one electric, then once all (most? some?) wrinkles are ironed out, convert the other side as well).  However, from my trip down the rabbit hole online (which actually doesn't seem all that deep) x2 of the 24kw motors seems like overkill.  Plus, they run at 96v, which requires a monster battery setup, which is our biggest hurdle financially being in the Caribbean.  Even the fancier setups I've seen seem to be closer to the 10-15kw range for a boat roughly our size.  The 12kw motor kits from Thunderstruck run at 48v which is much more manageable and seem like they would do the trick, but again...newb.

We'd like decent potential range, but we sail 95% of the time already and when motoring, we don't have the "need for speed"...we sailed about 2000 miles already with just the one motor as mostly backup and have had no real issues getting where we needed to go.  Running a conservative 1/2 power at something like 4-5 knots would be absolutely fine, while hopefully keeping up with solar, regen, and the genny.  Heck, even motoring at 3-4 knots while waiting on wind or even just motor-sailing in the really light stuff would suit us just fine too.  That said, when entering and leaving port and anchoring, or in the situations that always happen where being able to go pedal to the metal for a little bit can get you out of a jam, we don't want to find ourselves too wimpy on power.

Thoughts?

Thanks much.

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