BoatHowTo · video

What this video covers

Marine generator lifespan suffers most from chronic light loading, Nigel Calder explains in this Q&A with host Jan Attenstedt.0:57 Most boat generators are sized for peak AC load but must run at fixed speed regardless of demand, leaving them operating well below capacity the majority of the time.0:57 At light loads, conventional mechanical injection systems produce imprecise combustion, excess carbon accumulates in the exhaust, and the condition known as wet stacking kills the engine prematurely.1:25 The target operating range is 50–70% of rated load whenever the generator runs.1:35 One practical strategy to hit that range: pair the generator with a high-capacity battery bank that accepts charge aggressively, run the generator hard while charging, then switch to an inverter for the remaining power demand.1:55 Inverter-based generators that vary engine speed with load avoid the fixed-speed problem entirely, though Calder notes they are the exception.0:40 The core lesson is that duty cycle, not hours alone, determines generator longevity.

More from BoatHowTo

How to keep you TANK CLEAN in the days of BIODIESEL.. | Ask The Expert with NIGEL CALDERAug 2026PARALLELING Conductors for AMPACITY - is that SAFE?? | Ask The Expert with NIGEL CALDERAug 2026ENGINE OIL turns BLACK right after Oil Change?? | Ask The Expert with NIGEL CALDERAug 2026Same LAYUP RECOMMENDATIONS for FAME and HVO bio diesel? | Ask The Expert with NIGEL CALDERAug 2026

From BoatHowTo — see the channel’s boat, crew, and every analyzed video.

The Sailing Directory Newsletter

One email with the fleet's best finds — the moments, boats, and stories worth your watch time. Enter your own address to get your own copy.