Generator efficiency upgrade

Daybreak is a beautiful 2014 Fleming 58, pilot house trawler. Her owner was disappointed with the factory battery capacity and charge rate. It seemed that while running the generator for cooking and other domestic needs, the battery would never completely charge. The batteries installed from the factory had already been upgraded, and additional capacity was added, however the vessel struggled to maintain capacity overnight, even in night ship low consumption mode.



Daybreak was fitted with 8, Lifeline L-16, 6 volt batteries giving her an amp hour capacity of 400 amp hours at 24 volts D/C. On top of this inadequate battery storage capacity the boat was equipped with a 17 KW and a 9KW generator.

The bottleneck was in the A/C charging when running either generator all dc charging was handled by one outback inverter charger with a maximum output of 80 amps/2000 watts.

This is where Revision came in. We removed the old lead acid heavy bank, rebuilt the battery box and installed 12 BattleBorn BB10012, 100 amp hour 12VDC batteries in a 6P,2S configuration for a combined 600 amp hour usable capacity at 24 VDC. As for charging we wanted to maximise the generators rated capacities and run them at their most efficient load. Generator manufacturers all rate their products at maximum efficiency and design load of 80% This was our target, so we designed a dual generator approach.

By installing 4 2000 watt chargers and 2 4000 watt units the operator can select and deselect chargers at the dash according to the generator or shore power loads.

The final result is a vessel that can maintain a 16 hour battery only autonomy for hotel loads, and when it’s time to recharge, a simple 1 hour run of the 17 KW genset will suffice. 2 hours on the 9 KW and alternatively a two and a half hour runtime using alternators will bring the big lithium bank up to full capacity.

Daybreak console
Daybreak batteries
Daybreak generator