What are the advantages of a marine diesel genset over a less expensive, gasoline-powered generator found at home-supply stores?
Mark Matthews responds:
There are a number of reasons why a marine diesel genset is preferable to the less-expensive, gasoline-powered models found at the local hardware store. Consider the marine application and the isolation that typically goes along with life beyond the confines of the marina, and reliability becomes a central concern. For starters, a properly maintained diesel engine will normally last somewhere in the neighborhood of four times longer than a gasoline engine, and in the process it will use 60 percent less fuel, saving not only money, but maintenance headaches as well.
A diesel generator also means that only one type of fuel has to be used on board (for sailors with diesel-run auxiliary engines). The fuel supply for the generator can be plumbed from the boats main tanks. Gasoline is extremely volatile, heavier than air, and if allowed to collect in the confines of a boats hull, can mean disaster should static electricity or a source of ignition from faulty wiring enter the equation. Gasoline gives off explosive vapors at any temperature above 43 degrees Fahrenheit. In comparison, diesel is a safer fuel, and doesnt give off volatile vapors until reaching the 110-degree mark. While there are a number of both powerboats and sailboats still with gasoline inboard engines (outboards are safer by virtue of their location outside the boat, allowing perpetual ventilation), in my humble opinion any cruising sailboat should be fitted with a diesel engine for safety reasons.
Even if the wind and seas arent howling, the marine environment is a relentless one when it comes to gear. Anything non-"marinized" will rust and corrode, and a mobile hardware store unit will spend plenty of time bouncing around the cockpit in salty aira combo sure to leave rust marks throughout the cockpit or on deck, to say nothing of exhaust as well. I may be a little biased against gas engine generators (although I have seen them used on cruising boats) based on an incident where one almost burned a friends boat down during a lighted Christmas parade (the exhaust got too close to the fiberglass and left a burn mark on the gelcoat). The incident illustrates the dangers of hot machinery which doesn't have a specified place on board. My bias may also stem from the times boats have anchored next to me with such noisy contraptions puttering away on deck at sunset. I can understand the appeal of these devices' considerably less costly price, however, in the long run, an inboard diesel genset will last longer, be safer, and give everyone less grief.