48v narrowboat electrics

Hopefully this week, we will finalise the purchase of Elysium. I have a medium term plan to convert her to hybrid power using a 48v motor as well as the Lombardini 20HP diesel engine.

Elysium ( her name might change ) currently has a 12v system configured as below ( circuit drawn with kicad ) :

This is all fairly standard. However, Elysium’s 12v system needs upgrading and I have plans to convert Elysium to a hybrid diesel electric drive and will need a 48v high capacity supply for this. So, the questions is – should I install a 12v system for the short term or a ( complicated ) 48v system for the long term ?

Below is the proposed solution. I like Victron kit. The engine’s existing 12v alternator charges the cranking battery and the 12v/240v inverter feed one mains input to the quatro, the other being from shore power/generator. This has the minor advantage for being able to charge the 48v battery bank to its full capacity ( 14.4 bulk charge ).

The disadvantages are the unnecessary complexity, especially creating the 12v for the fridge, bilge pumps and comms radios. The design feels unsatisfying. In order to charge the 12v battery bank, both the quatro and the 12v charger will need to be running, with the power loss that entails.

The next image is a slight modification where we add a fictitious 48v input 12v 3 stage battery charger, I’m not sure these exist.

Of course the upgraded 12v only system is easier, it will just need replacing if I move to 48v propulsion :

So, that’s it for now.

Leave a Reply

Your email address will not be published. Required fields are marked *