Sunday, May 17, 2020

Re: [electricboats] 39' sloop conversion

I can tell you the max amperage you should get from the two charge controllers is 50amps.  I have a 38' trimaran at 9k lbs with the same motor and am at the end of the install but the beginning of testing.  I don't know the size of my prop but it's a two blade originally on a 30hp yanmar with a 2:1 reduction.  I can only run about 3knts around 20 amps and 4 around 50.  I've only made one test run and am planning on doing some more.  Someone on the list was advocating a 3:1 with a 4blade prop which I'm about to price out.  So the 3:1 is probably the right choice.  I have less weight than you but more wetted surface so I'm not sure how well we compare.  And this was with very light wind on the beam.



On May 17, 2020, at 9:36 AM, MATT <msteverson@gmail.com> wrote:

Hello all, I'm a longtime lurker, this is my first post, so please, be gentle.

We have lived on our 39' sloop for about 5 years now and are ready to convert to hybrid...this is the plan I've come up with and am looking for your critical analysis.

The boat is a custom build. It displaces about 18000 lbs all full, has a 3/4 length "scheel" keel, and only draws about 50".  We currently have a very good running yanmar 3gm30f that turns a 17" 2 blade max prop.  We've put in about 20k nm over the past few years and she solidly averages 6kts.  The engine is in the middle of the boat under the galley sink and makes A LOT of noise and stink and we're sick of it.  We've got a little extra time and money so we think this project could go a long way.

The plan
- 48V 12KW Thunderstuck ME1616 kit - currently its on backorder - with a 3:1 gear reduction
- About 15kw lithium battery bank (right now Thunderstruck has Valence 1.6kw batteries used for $350 each, so 8 of these, and the VC1 BMS they sell, I think would be easy to install and work well.)
- A 3.5-4kw diesel generator that is PURELY for recharging batteries using the thunderstruck TSM2500 kit with 2 chargers.  This should get me 70amps at 48volts running from 240VAC.  This is important because we live at anchor in the PNW year round.  We often have a long way to go with no wind, or sun and generally avoid marinas.  I will buy this used or rebuilt to save dollars.
- Run existing loads off of a DC-DC converter

- We have 500W of PV installed with 12V Victron charge controllers that keeps up with our daily usage.  I would like to get them putting electrons into the 48v bank and am wondering if there is a work-around with DC to DC converters or something so I don't have to buy all new CCs.  

I will be doing this install myself.  I'm confident with basic stuff like solar installs and alternators but this project will be a little out of my comfort range, I'm very much looking forward to it.  What is most important to me is to keep the system as simple and user friendly as possible mostly for resale purposes.  

Any advice/comments/questions/trashtalk would be appreciated.  

Matt

No comments:

Post a Comment